More stories

  • in

    Predator cue-induced plasticity of morphology and behavior in planthoppers facilitate the survival from predation

    To defend against predators, insects often modify their morphology, flexibly, to enhance survival and reproductive advantages. Here, we report that predation risks from either isolated predator or predator odor cues, induce a higher proportion of nymphs to developed into long-winged females among the parent generation, as well as among F1 generation offspring. Surprisingly, these previously threatened long-winged adults survived better when attacked by a predator owing to the enhanced agility level gained from risk experience. The long wing, and increased agility level, provide adaptive benefits for SBPHs to escape from predation and so are able to go on to reproduce.SBPHs responded more strongly to the caged predators (visual + odor risk cues) and predator odor cues, than just the visual cue of the predator. Different risk cues can elicit different levels of responses in prey33,34,35,36. For example, in the case of the Colorado potato beetle, volatile odor cues from the predator stronger reduced the beetle feeding on plants than predator visual and tactile cues35. But a visual cue has been shown to be crucial for insect pollinators detecting and avoiding flowers with predators37. Insect herbivores frequently communicate via chemical odors33,38. Exploiting the odor cue to perceive the presence of predators should have advantages, because the odor cue can be sensed from a long distance and penetrate the blocking effect of foliage or canopy structure39, enabling the prior detection of risks and the preparation of antipredation behaviors.In densely planted rice paddies, the active foraging behavior of rove beetle may serve as a selective pressure favouring the development in SBPHs of a chemical instead of visual pathway to detect the approach of a rove beetle. However, in the F1 generation, the influence of a predator odor cue on the proportion of winged forms was weaker than that of caged predators, indicating the combined effects of odor and visual cues might be stronger than only an odor cue, suggesting that visual cues cannot be ignored. In our experiments, sealed predator cadavers may have weakened the visual cue of the rove beetles, because the lack of motion did not fully represent the normal visual cue.SBPHs frequently exhibit wing plasticity in response to population density and food quality28,29. When nymph density is higher, or food has deteriorated, a higher proportion of macropters will arise28,29. The development of the winged form is thought to be a strategy for SBPHs to emigrate from inhospitable environments. However, we assumed, predation risks could also induce the occurrence of the winged form, because long wings might enable SBPHs to escape from predation. As expected, the results presented here show that a higher proportion of long-winged females and their offspring arose when nymphs or adults were previously exposed to predation risk, demonstrating that SBPHs can express morphologically plastic defenses in response to prior predation risk. Additionally, the higher proportion of wing forms was not only due to the increasing number of winged females (see Fig. 1, the number of winged females in “caged rove beetle” treatment was lower), but also the increasing proportion of winged females among female groups (the decreasing numbers and proportions of wingless females, Fig. 1). To date, similar patterns have only been shown in pea aphids, in which when predation risk (foot prints from lady beetles) is higher during the parent generation, a higher proportion of winged morphs arise in the offspring40,41. In our experiments, we tested the risk effects passing from nymphs to adults and from parents to their offspring with combined risk cues, an odor cue or a visual cue, which better reveals the capacity for flexible defense strategies within SBPHs and the nature of predation risks in the perpetual ‘arms race’ against predation. This is the first example of how insects can express both within- generational and transgenerational morphological plasticity as a defense strategy in response to prior predator threat, and we suggest that this phenomenon is likely to occur more widely.However, SBPHs do not only face a single lethal pressure from their environment as we discussed above. Nymph density, food quality, even the temperatures or photoperiods may play or interplay roles in the induction of wing plasticity in SBPHs28,29. In these situations, the responses of SBPHs may differ from present results, or opposite results can occur. As an example, the growth rates of snails vary depending on snail densities, food supply and the strength of predation risks. Growth rates were higher when snails were reared on high nutrients and in low densities, but decreased steeply as the predation risk increased. Conversely, the growth rate was lower at high densities and with high predation risk, but increased as nutrient availability increased42. As for SBPHs, the proportion of winged adults may be higher if we reared in higher densities combined with high predation risk, or may be lower if the nutrient condition of the rice plants increases (for example, higher fertilizer inputs benefit the development of planthoppers43) and predators are removed. This hypothesis needs to be tested. Further, the rice plant phenotypes (resistant or sensitive phenotypes) are important to the development of planthoppers or leafhoppers44,45,46, and tests of the interactive effects of plant phenotype, plant quality/quantity, nymph density and predation risk on the wing plasticity of SBPHs should provide insights into the evolution of insects within changing environments.Induced transgenerational defense plasticity as shown in SBPHs may be common in many organisms20,47. It allows parents to transfer their risk experience to offspring and promotes their evolutionary fitness20. When SBPH nymphs are exposed to predation risk, they are likely to develop into long-winged females, because it is an advantageous form for them in the current risk environment. However, such predation risk is variable in time and space, and SBPH parents cannot predict when or whether the predators will disappear. Thus, an appropriate strategy to enhance the survival rate of offspring in an unpredictable environment is to continue producing a higher proportion of long-winged forms. Within-generational and transgenerational plasticity of defense should be a successful adaptive defense strategy for SBPHs, given that rove beetle and other groups of predators such as predatory spiders are abundant all around the year in rice paddies.The higher mortality of SBPH nymphs when they experience predation risk, has been broadly addressed before24,48,49. Reduced food intake during risk periods may contribute to this poorer survival outcome, because insects are likely to alter their feeding behavior50,51, or shift from a high-risk host to a safer, but nutritionally inferior, one52, when they detect the presence of predators. However, we did not observe an apparent behavior change in threatened nymphs in our experiments, even those going on to be macropters, compared to the non-threatened ones. For example, changing feeding location, non-feeding related motility, an increase in jump frequency, etc. did not occur in threatened nymphs. Thus, behavior plasticity seems not to be invoked to explain this phenomenon. However, considering the food consumption of sap-sucking SBPHs is difficult to determine, experiments employing electrical penetration graph (EPG) techniques should be conducted to quantify the amounts of sap consumption during risk periods53. This will help to explain whether the higher mortality is due to a change of feeding behavior (less food intake). Furthermore, some obscure internal physiological plasticity may also cause the higher mortality of SBPH nymphs at risk. For example, increased oxidative damage and decreased assimilation efficiency during the risk period may weaken the survival success of SBPH nymphs. Unfortunately, few studies have verified this assumption, although it has been shown that different assimilation efficiencies may arise under predation risk17, or oxidative damage may be induced by predation risk resulting in a slower growth rate54 and decreased escape performance55.SBPHs exhibit sexual differences in both with- and trans- generational morphological plasticity in relation to defense, i.e., threatened nymphs/parents are more likely to develop into long-winged females, due to the different vulnerability of females and males to predation. This predation difference is particularly acute between short-winged females and males, given that the proportion of short-winged females is lower than that seen in control settings (Fig. 1), and we assume the level of vulnerability may depend on their body size and reproductive role. The body sizes of short-winged females are larger than those of long-winged females or males, causing them to be more vulnerable to predation because they are more highly preferred targets for predator. Also, the short-winged female needs to stay and deposit eggs in the bare rice stem, which increases the time window of exposure to predators while, by contrast, long-winged males are slim and are not required to lay eggs, and so should be not be heavily predated. It follows that short-winged females should be more vulnerable to predation than long-winged females or males. Hence, in SHPBs, increasing the proportion of long-wing females in a population creates greater opportunities to migrate to predator-free habitats for reproduction, while at the same time reducing their vulnerability to predation. We hypothesize that the sexual difference in responses should be adaptive, and might be inheritable if predation pressure frequently favors the long-winged forms among populations over multiple generations.Results presented here also show that previously threatened long-winged offspring survived better than previosuly non-threatened ones when attacked by P. fuscipes. Studies suggest prey-altered morphology in response to predation risks should confer a survival advantage (fitness gained), i.e., a better-developed defensive structure13,24, or refuge in having a larger size that increase survival success57. However, wings themselves are without protective functions for SBPHs, as seen in pea aphids41. Thus, we setup behavioral experiments to reveal how threatened long-winged adults may increase their survival when attacked by a predator. Results show threatened long- winged offspring (but not parents) are more active, and respond more quickly, than unthreatened ones, i.e., a higher number of attacks are needed for P. fuscipes to capture a previously threatened long-winged offspring than one that has not been threatened before. We suggest the increased agility level is not because of the long wing itself, but due to the enhanced muscle strength in the legs of long-winged adults, because in our observation, long-winged adults avoid attack mainly by jumping but not by flight, probably because a jump needs less reaction time than flight.We only observed transgenerational plasticity of induced behavioral defense in SBPHs. This generational difference (within- and trans-generational) in behavioral defense in SBPHs may reflect potential carry-over effects from parents. To our knowledge, the generational difference in defense has rarely been shown in insects, though in pea aphids a fluctuating expression of transgenerational defensive traits (long wing) over generations when predation risk was present or absent has been reported58. We also expect there will be cumulative effects59 accumulated by SBPHs from the parent generation to the F1 generation. However, we are not certain whether these effects exist in our experiments. To determine this, experiments examining defensive traits across multigeneration should be conducted.However, if predation risk increases the number of agile, long-winged SBPH adults, which are of benefit in respect of dispersal, migration, and thus spreading rice viruses, the application of P. fuscipes in biological control appears ultimately to weaken the control effectiveness. Also, a study with field experiments found that predatory ladybugs increase the number of dispersed aphid nymphs, especially in plants with lower resistance. However, surprising results show that the higher number of dispersed aphid nymphs will not necessarily translate into population growth because dispersed aphids are weak (less food intake) and more easily predated by predators60. Thus, the benefits of anti-predator defense in aphids will, over time, translate into negative developmental costs that suppress the aphid population. As for SBPHs, threatened long-winged females perform well in dispersal and defense, but worse in development and reproduction. Recent experiments reveal that previously threatened long-winged females have a longevity that is three days shorter, and produces about 60 fewer eggs per female, than non-threatened long-winged females (unpublished data). Consequently, these negative effects would eventually translate into lower population growth rates within SBPHs. Thus, the introduction of the predation risk from P. fuscipes to control SBPHs is workable, since field experiments in controlling western flower thrips and grasshoppers by exposure to predation risk have been successful49,61, and the main purpose of biological control is to suppress the pest population beneath the relevant economic threshold, and reduce plant mass loss without necessarily eliminating the pest altogether.This study advances the importance of predation risk on the induction of flexible anti-predation defenses in insect parents and their offspring, uncovers the mediating mechanisms, shows how this anti-predation defense expresses differently between sexes, and further explores the adaptation significance of these defense traits for insects exposed to unpredictable environments. These findings should prove important for predicting SBPH migration or dispersal, conducting effective pest control, and better understanding prey-predator interactions. However, future work should examine the effects of predation risks from other groups of predators or parasites on the physiological and behavioral plasticity of SBPHs. More

  • in

    Great Barrier Reef: accept ‘in danger’ status, there’s more to gain than lose

    WORLD VIEW
    18 August 2021

    Great Barrier Reef: accept ‘in danger’ status, there’s more to gain than lose

    The Australian government must embrace UNESCO’s assessment to marshal the resources needed to protect the unique coral ecosystem.

    Tiffany H. Morrison

    0

    Tiffany H. Morrison

    Tiffany H. Morrison is a political geographer specializing in marine interventions at James Cook University in Townsville, Australia.

    View author publications

    You can also search for this author in PubMed
     Google Scholar

    Share on Twitter
    Share on Twitter

    Share on Facebook
    Share on Facebook

    Share via E-Mail
    Share via E-Mail

    Download PDF

    No one denies the cascade of climate-induced coral bleaching that devastated huge portions of the Great Barrier Reef in 2016, nor the subsequent bleaching. No one questions the Queensland government’s 2019 report (see go.nature.com/3ckg) that the reef’s condition near the shore is poor.Yet last month, the World Heritage Committee of the United Nations organization UNESCO caved to lobbying from the Australian government — pressured by fossil-fuel, agricultural and mining interests — and kept the Great Barrier Reef off its list of ecosystems ‘in danger’. In my view, this decision is wrong, factually and strategically. It leaves both UNESCO and Australia weaker against the climate crisis.I study the governance of approximately 250 ecosystems with World Heritage status because of their outstanding value to humanity — including attempts to curtail runaway industrial development of Vietnam’s Ha Long Bay and overzealous urbanization along Florida’s Everglades wetlands.There are benefits to an in-danger listing: the Belize Barrier Reef Reserve System was placed on the list in 2009. The World Heritage Fund then provided technical and financial assistance for its restoration. By 2018, mangrove coverage was restored nearly to 1996 levels, with clearing in protected areas almost entirely curtailed. The whole maritime zone was under a moratorium on oil and gas production. Restoration work is ongoing, but the Belize reef is no longer on the list.
    Save reefs to rescue all ecosystems
    This July, UNESCO proposed to list the Great Barrier Reef as in danger owing to severe coral bleaching, poor water quality and inaction on climate change.In arguing against the listing, the Australian government did not directly deny the reef’s parlous state, but did play down its condition. The government also argued that the listing would decrease tourism revenues, that Australia had too little time to respond and should not be held responsible for global change, and that UNESCO should not supersede national sovereignty on climate-change policy.Australian environment minister Sussan Ley lobbied committee members from more than a dozen countries to override UNESCO’s recommendation. Australia avoided an in-danger listing in 2015 using similar tactics and by touting a sustainability plan. The following year saw the worst coral bleaching in the world’s history.But changes are in the wind. After back-to-back coral bleaching in 2016–17 and the tragic 2020 bush fires, more Australian voters, industries and even conservative politicians are calling for strong efforts against climate change.Accepting an in-danger listing for the reef could tip the balance past gridlock. More than 70% of Australians think that formally acknowledging the reef’s endangered state would spur action. In 1993, former US president Bill Clinton’s administration requested that UNESCO certify Florida’s Everglades as in danger. This helped to bring industry opponents on board to better manage coastal development. Had the Great Barrier Reef been listed as in danger in 2015, fossil-fuel developments in the catchment areas draining into the reef would have struggled to get approval.Australia’s most conservative politicians will argue that avoiding an in-danger listing in 2022 is necessary to boost economic development. But this will embarrass Australia later. As more marine heating occurs globally, Australia will struggle to defend its inaction on climate to the UN climate-change conference in November and to the World Heritage Committee next year. Even the Queensland Tourism Industry Council has said keeping the reef’s status under the spotlight is a “call to the world to do more on climate change”.
    Fevers are plaguing the oceans — and climate change is making them worse
    And undercutting the listing undermines the purpose of the World Heritage Committee. Since 1972, 41 ecosystems have been considered for the in-danger list — 27 of them more than once — but not officially inscribed, even though UNESCO and its advisory body had assessed these ecosystems as threatened, or more threatened than those already listed. The number of sites on the list has declined by almost one-third since 2001, although threats continue to grow and there are more ecosystems on the overall World Heritage List.However, destabilizing strategies are mainly due to a small group of nations — including countries in the Organisation for Economic Co-operation and Development, such as Australia and Spain. World Heritage status and in-danger listings often work as intended: the managers of 73% of sites do comply with their responsibilities.Concerned observers are helping the World Heritage Committee to protect itself from political manipulation. In February 2020, a consortium of 76 organizations and individuals petitioned UNESCO to consider climate change in its World Heritage decisions. A nascent international network known as World Heritage Watch hopes to provide more oversight and monitoring of self-interested states. Ecologists and non-profit organizations are using remote sensing and citizen science to track and expose degradation of protected areas (see go.nature.com/2xn1) and hold governments accountable.UNESCO and its World Heritage Committee grasp the stakes. A new draft policy clearly states that climate-related degradation of a World Heritage Area can be used as the basis for in-danger listing; it will probably be ratified later this year at the UNESCO General Assembly. This policy will shine a harsh light on the intensifying geopolitics of climate change. Advanced economies, such as Australia, with high per-capita emissions but limited climate action, will need to find alternative ways to protect resources and jobs.

    Nature 596, 319 (2021)
    doi: https://doi.org/10.1038/d41586-021-02220-3

    Related Articles

    Fevers are plaguing the oceans — and climate change is making them worse

    Save reefs to rescue all ecosystems

    Subjects

    Climate change

    Conservation biology

    Government

    Latest on:

    Climate change

    ‘Polluter pays’ policy could speed up emission reductions and removal of atmospheric CO2
    News & Views 16 AUG 21

    Warming world, women in science — the week in infographics
    News 13 AUG 21

    IPCC climate report: Earth is warmer than it’s been in 125,000 years
    News 09 AUG 21

    Government

    Brazilian road proposal threatens famed biodiversity hotspot
    News 17 AUG 21

    The world must cooperate to avoid a catastrophic space collision
    Editorial 11 AUG 21

    From the archive
    News & Views 10 AUG 21

    Jobs

    Locum Associate or Senior Editor, Immunology

    Springer Nature
    London, United Kingdom

    Position title: Postdoctoral Research Fellows – Air Force Science & Technology Fellowship Program

    National Academies of Sciences, Engineering, and Medicine
    Various locations in the U.S., United States

    Postdoctoral Research Associates – NRC Research Associateship Programs

    National Academies of Sciences, Engineering, and Medicine
    Various locations in the U.S., United States

    Research Associate in the Centre for Developmental Neurobiology

    King’s College London (KCL)
    London, United Kingdom

    Nature Briefing
    An essential round-up of science news, opinion and analysis, delivered to your inbox every weekday.

    Email address

    Yes! Sign me up to receive the daily Nature Briefing email. I agree my information will be processed in accordance with the Nature and Springer Nature Limited Privacy Policy.

    Sign up More

  • in

    Intermediate ice scour disturbance is key to maintaining a peak in biodiversity within the shallows of the Western Antarctic Peninsula

    1.Dell, J. et al. Interaction diversity maintains resiliency in a frequently disturbed ecosystem. Front. Ecol. Evol. 7, 145 (2019).Article 

    Google Scholar 
    2.White, P. S. & Pickett, S. T. A. In The Ecology of Natural Disturbance and Patch Dynamics (eds S. T. A. Pickett & P. S. White) 3–13 (Academic Press, 1985).3.Newman, E. A. Disturbance ecology in the anthropocene. Front. Ecol. Evolut. https://doi.org/10.3389/fevo.2019.00147 (2019).Article 

    Google Scholar 
    4.Barnosky, A. D. et al. Approaching a state shift in Earth’s biosphere. Nature 486, 52–58 (2012).ADS 
    CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    5.Yuan, Z., Jiao, F., Li, Y. & Kallenbach, R. L. Anthropogenic disturbances are key to maintaining the biodiversity of grasslands. Sci. Rep. 6, 22132 (2016).ADS 
    CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    6.Hughes, A. R., Byrnes, J. E., Kimbro, D. L. & Stachowicz, J. J. Reciprocal relationships and potential feedbacks between biodiversity and disturbance. Ecol. Lett. 10, 849–864. https://doi.org/10.1111/j.1461-0248.2007.01075.x (2007).Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    7.Connell, J. H. & Slatyer, R. O. Mechanisms of succession in natural communities and their role in community stability and organization. Am. Nat. 111, 1119–1144 (1977).Article 

    Google Scholar 
    8.Connell, J. H. Diversity in tropical rain forests and coral reefs. Science 199, 1302–1310 (1978).ADS 
    CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    9.Fox, J. W. The intermediate disturbance hypothesis should be abandoned. Trends Ecol. Evol. 28, 86–92. https://doi.org/10.1016/j.tree.2012.08.014 (2013).Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    10.Sheil, D. & Burslem, D. F. Disturbing hypotheses in tropical forests. Trends Ecol. Evol. 18, 18–26 (2003).Article 

    Google Scholar 
    11.Teixidó, N., Garrabou, J., Gutt, J. & Arntz, W. E. Recovery in Antarctic benthos after iceberg disturbance: Trends in benthic composition, abundance and growth forms. Mar. Ecol. Prog. Ser. 278, 1–16. https://doi.org/10.3354/meps278001 (2004).ADS 
    Article 

    Google Scholar 
    12.Teixidó, N., Garrabou, J., Gutt, J. & Arntz, W. Iceberg disturbance and successional spatial patterns: the case of the shelf Antarctic benthic communities. Ecosystems 10, 143–158 (2007).Article 

    Google Scholar 
    13.Johst, K., Gutt, J., Wissel, C. & Grimm, V. Diversity and disturbances in the Antarctic megabenthos: Feasible versus theoretical disturbance ranges. Ecosystems 9, 1145–1155 (2006).Article 

    Google Scholar 
    14.Mackey, R. L. & Currie, D. J. The diversity-disturbance relationship: Is it generally strong and peaked?. Ecology 82, 3479–3492. https://doi.org/10.1890/0012-9658(2001) (2001).Article 

    Google Scholar 
    15.Huston, M. A. Disturbance, productivity, and species diversity: Empiricism vs. logic in ecological theory. Ecology 95, 2382–2396. https://doi.org/10.1890/13-1397.1 (2014).Article 

    Google Scholar 
    16.Smale, D. A., Brown, K. M., Barnes, D. K., Fraser, K. P. & Clarke, A. Ice scour disturbance in Antarctic waters. Science 321, 371. https://doi.org/10.1126/science.1158647 (2008).ADS 
    CAS 
    Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    17.Griffiths, H. J., Danis, B. & Clarke, A. Quantifying Antarctic marine biodiversity: The SCAR-MarBIN data portal. Deep Sea Res. Part II 58, 18–29. https://doi.org/10.1016/j.dsr2.2010.10.008 (2011).ADS 
    Article 

    Google Scholar 
    18.Grange, L. J. & Smith, C. R. Megafaunal communities in rapidly warming fjords along the West Antarctic Peninsula: Hotspots of abundance and beta diversity. PLoS ONE 8, e77917 (2013).ADS 
    PubMed 
    PubMed Central 
    Article 
    CAS 

    Google Scholar 
    19.Gutt, J., Griffiths, H. J. & Jones, C. D. Circumpolar overview and spatial heterogeneity of Antarctic macrobenthic communities. Mar. Biodivers. 43, 481–487. https://doi.org/10.1007/s12526-013-0152-9 (2013).Article 

    Google Scholar 
    20.Potthoff, M., Johst, K. & Gutt, J. How to survive as a pioneer species in the Antarctic benthos: Minimum dispersal distance as a function of lifetime and disturbance. Polar Biol. 29, 543–551 (2006).Article 

    Google Scholar 
    21.Convey, P. et al. The spatial structure of Antarctic biodiversity. Ecol. Monogr. 84, 203–244 (2014).Article 

    Google Scholar 
    22.Peck, L. S., Brockington, S., Vanhove, S. & Beghyn, M. Community recovery following catastrophic iceberg impacts in a soft-sediment shallow-water site at Signy Island, Antarctica. Mar. Ecol Progr. Ser. 186, 1–8 (1999).ADS 
    Article 

    Google Scholar 
    23.Lee, H., Vanhove, S., Peck, L. & Vincx, M. Recolonisation of meiofauna after catastrophic iceberg scouring in shallow Antarctic sediments. Polar Biol. 24, 918–925. https://doi.org/10.1007/s003000100300 (2001).Article 

    Google Scholar 
    24.Armstrong, T. World Meteorological Organization. WMO sea-ice nomenclature. Terminology, codes and illustrated glossary. Edition 1970. Geneva, Secretariat of the World Meteorological Organization, 1970. [ix], 147 p. [including 175 photos]+ corrigenda slip. (WMO/OMM/BMO, No. 259, TP. 145.). J. Glaciol. 11, 148–149 (1972).25.Robinson, B. J., Barnes, D. K. & Morley, S. A. Disturbance, dispersal and marine assemblage structure: A case study from the nearshore Southern Ocean. Mar. Environ. Res. 160, 105025 (2020).CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    26.Gutt, J., Starmans, A. & Dieckmann, G. Impact of iceberg scouring on polar benthic habitats. Mar. Ecol. Prog. Ser. 137, 311–316 (1996).ADS 
    Article 

    Google Scholar 
    27.Barnes, D. K. A. & Conlan, K. E. Disturbance, colonization and development of Antarctic benthic communities. Philos. Trans. R. Soc. Lond. B Biol. Sci. 362, 11–38. https://doi.org/10.1098/rstb.2006.1951 (2007).Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    28.Smale, D. A. Ecological traits of benthic assemblages in shallow Antarctic waters: Does ice scour disturbance select for small, mobile, secondary consumers with high dispersal potential?. Polar Biol. 31, 1225–1231. https://doi.org/10.1007/s00300-008-0461-9 (2008).Article 

    Google Scholar 
    29.Barnes, D. K. A. The influence of ice on polar nearshore benthos. J. Mar. Biol. Assoc. U.K. 79, 401–407 (1999).Article 

    Google Scholar 
    30.Gutt, J. On the direct impact of ice on marine benthic communities, a review. Polar Biol. 24, 553–564 (2001).Article 

    Google Scholar 
    31.Barnes, D. K. A. & Tarling, G. A. Polar oceans in a changing climate. Curr. Biol. 27, R454–R460. https://doi.org/10.1016/j.cub.2017.01.045 (2017).CAS 
    Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    32.Barnes, D. K. A., Fleming, A., Sands, C. J., Quartino, M. L. & Deregibus, D. Icebergs, sea ice, blue carbon and Antarctic climate feedbacks. Philos. Trans. R. Soc. A Math. Phys. Eng. Sci. 376, 20170176. https://doi.org/10.1098/rsta.2017.0176 (2018).ADS 
    Article 

    Google Scholar 
    33.Cook, A. J., Fox, A. J., Vaughan, D. G. & Ferrigno, J. G. Retreating glacier fronts on the Antarctic Peninsula over the past half-century. Science 308, 541–544. https://doi.org/10.1126/science.1104235 (2015).ADS 
    CAS 
    Article 

    Google Scholar 
    34.Cook, A. et al. Ocean forcing of glacier retreat in the western Antarctic Peninsula. Science 353, 283–286 (2016).ADS 
    CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    35.Clarke, A. et al. Climate change and the marine ecosystem of the western Antarctic Peninsula. Philos. Trans. R. Soc. Lond. B Biol. Sci. 362, 149–166. https://doi.org/10.1098/rstb.2006.1958 (2007).Article 
    PubMed 

    Google Scholar 
    36.Turner, J. & Comiso, J. Solve Antarctica’s sea-ice puzzle. Nat. News 547, 275 (2017).CAS 
    Article 

    Google Scholar 
    37.Meredith, M. P. & King, J. C. Rapid climate change in the ocean west of the Antarctic Peninsula during the second half of the 20th century. Geophys. Res. Lett. https://doi.org/10.1029/2005GL024042 (2005).Article 

    Google Scholar 
    38.Barnes, D. K. A. & Souster, T. Reduced survival of Antarctic benthos linked to climate-induced iceberg scouring. Nat. Clim. Chang. 1, 365–368. https://doi.org/10.1038/nclimate1232 (2011).ADS 
    Article 

    Google Scholar 
    39.Parkinson, C. L. Global sea ice coverage from satellite data: Annual cycle and 35-yr trends. J. Clim. 27, 9377–9382. https://doi.org/10.1175/jcli-d-14-00605.1 (2014).ADS 
    Article 

    Google Scholar 
    40.Rogers, A. et al. Antarctic futures: An assessment of climate-driven changes in ecosystem structure, function, and service provisioning in the Southern Ocean. Ann. Rev. Mar. Sci. 12, 87–120 (2020).CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    41.Morley, S. A. et al. Global drivers on Southern Ocean ecosystems: Changing physical environments and anthropogenic pressures in an Earth system. Front. Mar. Sci. 7, 1097 (2020).Article 

    Google Scholar 
    42.Barnes, D. K. et al. Blue carbon gains from glacial retreat along Antarctic fjords: What should we expect?. Glob. Change Biol. 26, 2750–2755 (2020).ADS 
    Article 

    Google Scholar 
    43.Barnes D. K. A. Blue carbon on polar and subpolar seabeds. In Carbon capture, utilization and sequestration (InTech, 2018). https://doi.org/10.5772/intechopen.78237.44.Bowler, D. et al. The geography of the Anthropocene differs between the land and the sea. bioRxiv https://doi.org/10.1101/432880 (2019).Article 

    Google Scholar 
    45.Arntz, W., Brey, T. & Gallardo, V. Antarctic zoobenthos. Oceanogr. Mar. Biol. 32, 241–304 (1994).
    Google Scholar 
    46.Clarke, A. Marine benthic populations in Antarctica: Patterns and processes. Antarct. Res. Ser. 70, 373–388 (1996).Article 

    Google Scholar 
    47.Fillinger, L., Janussen, D., Lundälv, T. & Richter, C. Rapid glass sponge expansion after climate-induced Antarctic ice shelf collapse. Curr. Biol. 23, 1330–1334 (2013).CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    48.Clarke, A., Meredith, M. P., Wallace, M. I., Brandon, M. A. & Thomas, D. N. Seasonal and interannual variability in temperature, chlorophyll and macronutrients in northern Marguerite Bay, Antarctica. Deep Sea Res. Part II 55, 1988–2006. https://doi.org/10.1016/j.dsr2.2008.04.035 (2008).ADS 
    Article 

    Google Scholar 
    49.Barnes, D. K. A. Iceberg killing fields limit huge potential for benthic blue carbon in Antarctic shallows. Glob. Chang. Biol. 23, 2649–2659. https://doi.org/10.1111/gcb.13523 (2017).ADS 
    Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    50.Pinkerton, M., Bradford-Grieve, J., Bowden, D. & Cummings, V. Benthos: Trophic modelling of the Ross Sea. Support. Docum. CCAMLR Sci. 17, 1–31 (2010).
    Google Scholar 
    51.Pielou, E. Shannon’s formula as a measurement of species diversity: It’s use and disuse. Am. Nat. 100, 463–465 (1966).Article 

    Google Scholar 
    52.Fisher, R. A., Corbet, A. S. & Williams, C. B. The relation between the number of species and the number of individuals in a random sample of an animal population. J. Anim. Ecol. 1, 42–58 (1943).Article 

    Google Scholar 
    53.Everitt, B. & Skrondal, A. The Cambridge Dictionary of Statistics Vol. 106 (Cambridge University Press, Cambridge, 2002).MATH 

    Google Scholar 
    54.Smale, D. A., Barnes, D. K. A. & Fraser, K. P. P. The influence of ice scour on benthic communities at three contrasting sites at Adelaide Island, Antarctica. Aust. Ecol. 32, 878–888. https://doi.org/10.1111/j.1442-9993.2007.01776.x (2007).Article 

    Google Scholar 
    55.Peck, L. S., Convey, P. & Barnes, D. K. A. Environmental constraints on life histories in Antarctic ecosystems: Tempos, timings and predictability. Biol. Rev. 81, 75–109. https://doi.org/10.1017/s1464793105006871 (2006).Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    56.Waller, C., Worland, M., Convey, P. & Barnes, D. Ecophysiological strategies of Antarctic intertidal invertebrates faced with freezing stress. Polar Biol. 29, 1077–1083 (2006).Article 

    Google Scholar 
    57.Barnes, D. K. A. Polar zoobenthos blue carbon storage increases with sea ice losses, because across-shelf growth gains from longer algal blooms outweigh ice scour mortality in the shallows. Glob. Chang Biol. 23, 5083–5091. https://doi.org/10.1111/gcb.13772 (2017).ADS 
    Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    58.Smith, C. R., Mincks, S. & DeMaster, D. J. A synthesis of bentho-pelagic coupling on the Antarctic shelf: Food banks, ecosystem inertia and global climate change. Deep Sea Res. Part II 53, 875–894 (2006).ADS 
    Article 

    Google Scholar 
    59.Jansen, J. et al. Abundance and richness of key Antarctic seafloor fauna correlates with modelled food availability. Nat. Ecol. Evolut. 2, 71–80 (2018).Article 

    Google Scholar 
    60.Henley, S. F. et al. Changing biogeochemistry of the Southern Ocean and its ecosystem implications. Front. Mar. Sci. 7, 581 (2020).Article 

    Google Scholar 
    61.Marshall, G. J. et al. Causes of exceptional atmospheric circulation changes in the Southern Hemisphere. Geophys. Res. Lett. 31, 14 (2004).Article 

    Google Scholar 
    62.Ashton, G. V., Morley, S. A., Barnes, D. K., Clark, M. S. & Peck, L. S. Warming by 1 C drives species and assemblage level responses in Antarctica’s marine shallows. Curr. Biol. 27, 2698-2705e2693 (2017).CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    63.Riesgo, A. et al. Some like it fat: Comparative ultrastructure of the embryo in two demosponges of the genus Mycale (order poecilosclerida) from Antarctica and the Caribbean. PLoS ONE 10, e0118805 (2015).PubMed 
    PubMed Central 
    Article 
    CAS 

    Google Scholar 
    64.Toszogyova, A. & Storch, D. Global diversity patterns are modulated by temporal fluctuations in primary productivity. Glob. Ecol. Biogeogr. 28, 1827–1838 (2019).Article 

    Google Scholar 
    65.Clark, G. F. et al. Light-driven tipping points in polar ecosystems. Glob. Change Biol. 19, 3749–3761 (2013).ADS 
    Article 

    Google Scholar 
    66.Brockington, S., Clarke, A. & Chapman, A. Seasonality of feeding and nutritional status during the austral winter in the Antarctic sea urchin Sterechinus neumayeri. Mar. Biol. 139, 127–138 (2001).Article 

    Google Scholar 
    67.Fratt, D. B. & Dearborn, J. Feeding biology of the Antarctic brittle star Ophionotus victoriae (Echinodermata: Ophiuroidea). Polar Biol. 3, 127–139 (1984).Article 

    Google Scholar 
    68.Sahade, R., Tatián, M. & Esnal, G. B. Reproductive ecology of the ascidian Cnemidocarpa verrucosa at Potter Cove, South Shetland Islands, Antarctica. Mar. Ecol. Progr. Ser. 272, 131–140 (2004).ADS 
    Article 

    Google Scholar 
    69.Dayton, P. K. et al. Recruitment, growth and mortality of an Antarctic hexactinellid sponge, Anoxycalyx joubini. PLoS ONE 8, e56939 (2013).ADS 
    CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    70.Vacchi, M., Cattaneo-Vietti, R., Chiantore, M. & Dalù, M. Predator-prey relationship between the nototheniid fish Trematomus bernacchii and the Antarctic scallop Adamussium colbecki at Terra Nova Bay (Ross Sea). Antarct. Sci. 12, 64–68 (2000).ADS 
    Article 

    Google Scholar 
    71.Sheil, D. & Burslem, D. F. Defining and defending Connell’s intermediate disturbance hypothesis: a response to Fox. Trends Ecol. Evol. 28, 571–572. https://doi.org/10.1016/j.tree.2013.07.006 (2013).Article 
    PubMed 
    PubMed Central 

    Google Scholar  More

  • in

    Environmental stress leads to genome streamlining in a widely distributed species of soil bacteria

    A. Strain sampling and isolationBradyrhizobium is a commonly occurring genus in soil [21]. Closely related Bradyrhizobium diazoefficiens (previously Bradyrhizobium japonicum) strains were isolated from soil, as previously described [20, 22]. In brief, Bradyrhizobium isolates that formed symbiotic associations with a foundational legume species in the censused region, Acacia acuminata, were isolated from soil sampled along a large region spanning ~300,000 km2 in South West Australia, a globally significant biodiversity hotspot [23]. In total 60 soil samples were collected from twenty sites (3 soil samples per site; Supplementary Fig. S1) and 380 isolates were sequenced (19 isolates per site, 5 or 6 isolates per soil sample, each isolate re-plated from a single colony at least 2 times). Host A. acuminata legume plants were inoculated with field soil in controlled chamber conditions and isolates were cultured on Mannitol Yeast agar plates from root nodules (see [20, 22] for details). A total of 374 strains were included in this study after removing 5 contaminated samples and one sample that was a different Bradyrhizobium species; non- Bradyrhizobium diazoefficiens sample removal was determined from 16S rRNA sequences extracted from draft genome assemblies (Method C) using RNAmmer [24].B. Environmental variation among sampled sitesIn this study, I focus on environmental factors (temperature, rainfall, soil pH and salinity) previously identified to impact either rhizobia growth performance, functional fitness or persistence in soil [25,26,27,28] and where a directionality of rhizobial stress response could be attributed with respect to environmental variation present in the sampled region (i.e. stress occurs at high temperatures, low rainfall, high acidity and high salinity). Each environmental factor was standardised to a mean of 0 and a standard deviation of 1, and pH and rainfall scales were reversed to standardise stress responses directions so that low stress is at low values and high stress is at high values for all factors (Supplementary Fig. S2). Additionally, salinity was transformed using a log transformation (log(x + 0.01) to account for some zeroes) prior to standardisation.C. Isolate sequencing and pangenome annotationIllumina short reads (150 bp paired-end) were obtained and draft genome assemblies were generated using Unicycler from a previous study [29]. Resulting assemblies were of good assembly quality (99.2% of all strains had >95.0% genome completeness score according to BUSCO [30]; Table S1; assembled using reads that contained nominal 0.016 ± 0.00524% non-prokaryotic DNA content across all 374 isolates, according to Kraken classification [31]). Protein coding regions (CDS regions) were identified using Prokka [32] and assembled into a draft pangenome using ROARY [33], which produced a matrix of counts of orthologous gene clusters (i.e. here cluster refers to a set of protein-coding sequences containing all orthologous variants from all the different strains, grouped together and designated as a single putative gene). Gene clusters that occurred in 99% of strains were designated as ‘core genes’ and used to calculate the ‘efficiency of selection’ [34, 35] (measured as dN/dS, Method G.2) and population divergence measured as Fixation Index ‘Fst’, Method H) across each environmental stress factor. The identified gene clusters were then annotated using eggNOG-mapper V2 [36] and the strain by gene cluster matrix was reaggregated using the Seed ortholog ID returned by eggNOG-mapper as the protein identity. Out of the total 2,744,533 CDS regions identified in the full sample of 374 strains, eggNOG-mapper was able to assign 2,612,345 of them to 91,230 unique Seed orthologs. These 91,230 protein coding genes constituted the final protein dataset for subsequent analyses.D. Calculation and statistical analysis of gene richness and pangenome diversity along the stress gradientGene richness was calculated as the total number of unique seed orthologues for each strain (i.e. genome). Any singleton genes that occurred in only a single strain, as well as ‘core’ genes that occurred in every strain (for symmetry, and because these are equally uninformative with respect to variation between strains) were removed, leaving 74,089 genes in this analysis. Gene richness (being count data) was modelled on a negative binomial distribution (glmer.nb function) as a function of each of the four environmental stressors as predictors using the lme4 package in R [37], also accounting for hierarchical structure in the data by including site and soil sample as random effects.To rule out potentially spurious effects of assembly quality (i.e. missed gene annotations due to incomplete draft genomes) on key findings, I confirmed no significant association between gene richness and genome completeness (r = 0.042, p = 0.4224, Fig. S3).Finally, pangenome diversity was calculated as the total number of unique genes that occurred in each soil sample (since multiple strains were isolated from a single soil sample). Pangenome diversity was modelled the same as gene richness, except here soil sample was not included as a random effect.E. Calculation of network and duplication traits for each geneI used the seed orthologue identifier from eggNOG-mapper annotations to query matching genes within StringDB ([38]; https://string-db.org/), which collects information on protein-protein interactions. Out of 91,230 query seed orthologues, 73,126 (~80%) returned a match in STRING. For matching seed orthologue hits, a network was created by connecting any proteins that were annotated as having pairwise interactions in the STRING database using the igraph package in R [39]. Two vertex-based network metrics were calculated for each gene: betweenness centrality, which measures a genes tendency to connect other genes in the gene network, and mean cosine similarity, which is a measure of how much a gene’s links to other genes are similar to other genes.Betweenness centrality was calculated using igraph (functional betweenness). For mean cosine similarity, a pairwise cosine similarity was first calculated between all genes. To do this, the igraph network object was converted into a (naturally sparse yet large) adjacency matrix and the cosSparse function in qlcMatrix in R [40] was used to calculate cosine similarity between all pairs of genes. To obtain an overall cosine similarity trait value for each gene, the average pairwise cosine similarity to all other genes in the network was calculated.Finally, gene duplication level was calculated for each gene as one additional measure of ‘redundancy’, by calculating the average number of gene duplicates found within the same strain. Duplicates were identified as CDS regions with the same Seed orthologue ID.F. Gene distribution modelsTo determine how gene traits predict accessory genome distributions patterns along the stress gradients, I first calculated a model-based metric (hereafter and more specifically a standardised coefficient, ‘z-score’) of the relative tendency of each gene to be found in different soil samples across the four stress gradients (heat, salinity, acidity, and aridity). This was achieved by modelling each gene’s presence or absence in a strain as a function of the four stress gradients, with site and soil sample as a random effect, using a binomial model in lme4 (the structure of the model being the same as the gene richness model, only the response is different). To reduce computational overhead, these models were only run for the set of genes that were used in the gene richness analysis (e.g. after removing singletons and core genes), and which had matching network traits calculated (e.g. they occurred in the STRING database; n = 64,867 genes). Distribution models were run in tandem for each gene using the manyany function in the R package mvabund [41]. Standardised coefficients, or z-scores (coefficient/standard error) indicating the change in the probability of occurrence for each gene across each of the stress gradients were extracted. More negative coefficients correspond to genes that are more likely to be absent in high stress (and vice versa for positive coefficients).To determine how network and duplication traits influence the distribution of genes across the stress gradient, I performed a subsequent linear regression model where the gene’s z-scores was the response and gene traits as predictors. The environmental stress type (i.e. acidity, aridity, heat and salinity) was included as a categorical predictor, and the interaction between stress category and gene function traits were used to infer the influence of gene function traits on gene distributions in a given stress type (see Supplementary Methods S1 for z-score transformation).G. Quantifying molecular signals of natural selection on accessory and core genesTo examine molecular signatures of selection in accessory and core genes, I calculated dN/dS for a subsample of the total pool (n=74,089 genes), which estimates the efficiency of selection [34, 35]. Two major questions relevant to dN/dS that are addressed here require a different gene subsampling approach:(1) Do variable environmental stress responses lead to different dN/dS patterns among accessory genes?Here, I subsampled accessory genes (total accessory gene pool across 374 strains, 74,089) to generate and compare dN/dS among 3 categorical groups, each representing a different level of stress response based on their z-scores (accessory genes that either strongly increase, decrease or have no change in occurrence as stress increases; n = 1000 genes/category; see Supplementary Methods S2 for subsample stratification details).For each gene, sequences were aligned using codon-aware alignment tool, MACSE v2 [42]. dN/dS was estimated by codon within each gene using Genomegamap’s Bayesian model-based approach [43], which is a phylogeny-free method optimised for within bacterial species dN/dS calculation (see Supplementary Methods S3 for dN/dS calculation/summarisation; S9 for xml configuration). The proportion of codons with dN/dS that were credibly less than 1 (purifying selection) and those credibly greater than 1 (positive selection) were analysed, with respect to the genes’ occurrence response to stress. Specifically, I modelled the proportion of codons with dN/dS  1 was overall too low to analyse in this way, so the binary outcome (a gene with any codons with dN/dS  > 1 or not) was modelled using a binomial response model with the response categories as predictors (see Supplementary Methods S4 for details of both models).(2) Does dN/dS among microbial populations vary across environmental stress?Here, I compared the average change in dN/dS in core genes present across all environments at the population level (i.e. all isolates from one soil sample), which is used here to measure the change in the efficiency of selection across each stress gradient. Core genes were used since they occur in all soil samples, allowing a consistent set and sample size of genes to be used in the population-level dN/dS calculation. This contrasts with the previous section, which quantifies gene-level dN/dS on extant accessory genes that intrinsically have variable presence or absence across soil samples. For computational feasibility, 500 core genes were subsampled (total core 1015 genes) and, for each gene, individual strain variants were collated into a single fasta file based on soil sample membership, such that dN/dS could be calculated separately for each gene within each soil sample (i.e. 60 soil samples × 500 genes = 30,000 fasta files). Each fasta file was then aligned in MACSE and dN/dS calculated using the same methodology for accessory genes (Supplementary Method S3). This enabled the average dN/dS in a sample to be associated with soil-sample level environmental stress variables. Specifically, I modelled the mean proportion of codons with dN/dS  1 due to overall rarity of positive selection (average proportion of genes where at least 1 codon with dN/dS  > 1 was ~0.006). This low level of positive selection is expected for core genes which tend to be under strong selective constraint.H. Calculation and analysis of Fixation index (Fst) along stress gradientsUsing the core genome alignment (all SNPs among 1015 core genes) generated previously with ROARY, I computed pairwise environmentally-stratified Fst. Each soil sample (n = 60) was first placed into one of 5 bins based on their distances in total environmental stress space (using all four stress gradients), with the overall goal of generating roughly evenly sized bins such that the environmental similarity of stress was greater within bins than between (see Supplementary Methods S6 and Fig. S4 for clustering algorithm details). Next, fasta alignments were converted to binary SNPs using the adegenet package. Pairwise Fst between all strains (originating from a particular soil sample) within a single bin was calculated using StAMPP in R [44]. For each strain pair, the average of the two stress gradient values was assigned.The relationship between pairwise Fst and the average stress value was evaluated using a linear regression model with each of the four stress values as predictors. Since the analysis uses pairwise data (thus violating standard independence assumptions), the significance of the relationship was determined using a permutation test (see Supplementary Methods S7 for details).I. Chromosomal structure analysis of gene loss patternsTo gain insight into structural variation and test for regional hotspots in gene loss along the chromosome, I mapped each gene’s stress response (i.e. probability of loss or gain indicated by each genes z-score) onto a completed Bradyrhizobium genome (strain ‘36_1’ from the same set of 374 strains (Genbank CP067102.1; [45]). Putative CDS positions on the complete genome were determined using Prokka and annotated with SEED orthologue ID’s using eggNOG-mapper. Matching accessory genes derived from the full set of 374 incomplete draft genomes (n = 74,089) were mapped to positions on the complete genome (6274 matches). The magnitude of gene loss or gain (as measured by their standardised z-scores for each environment from the gene distribution models; see Method F) was then modelled across the genome using a one-dimensional spatial smoothing model. This model was implemented in R INLA [46] (www.r-inla.org), and models a response in a one-dimensional space using a Matern covariance-based random effect. The method uses an integrated nested Laplace approximation to a Bayesian posterior distribution, with a cyclical coordinate system to accommodate circular genomes. The model accounts for spatial non-independence among sites and produces a continuous posterior distribution of average z-score predictions along the entire genome, which was then used to visualise potential ‘hotspots’ of gene loss or gain. The modelling procedure was repeated, instead with gene network traits, such that model predictions of similarity and betweenness could be visualised on the reference chromosome. More

  • in

    Correction: Divergence of a genomic island leads to the evolution of melanization in a halophyte root fungus

    State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing, ChinaZhilin Yuan, Huanshen Wei & Long PengResearch Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou, ChinaZhilin Yuan, Xinyu Wang, Huanshen Wei & Long PengFungal Genomics Laboratory (FungiG), College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, ChinaIrina S. Druzhinina & Feng CaiDepartment of Food Science, University of Massachusetts, Amherst, MA, USAJohn G. GibbonsState Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, ChinaZhenhui ZhongDepartment of Molecular, Cell and Developmental Biology, University of California, Los Angeles, CA, USAZhenhui ZhongDepartment of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, BelgiumYves Van de PeerVIB Center for Plant Systems Biology, Ghent, BelgiumYves Van de PeerCentre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Hatfield, South AfricaYves Van de PeerAdaptive Symbiotic Technologies, University of Washington, Seattle, WA, USARussell J. RodriguezKey Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization at College of Landscape Architecture, Fujian Agriculture and Forestry University, Fuzhou, ChinaZhongjian LiuState Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, ChinaQi Wu & Guohui ShiKey Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, ChinaJieyu WangBeijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, ChinaFrancis M. MartinUniversité de Lorraine, INRAE, UMR Interactions Arbres/Micro-Organismes, Centre INRAE Grand Est Nancy, Champenoux, FranceFrancis M. Martin More

  • in

    Exposure to foreign gut microbiota can facilitate rapid dietary shifts

    1.Shiels, A. B. et al. Dietary niche differentiation among three species of invasive rodents (Rattus rattus, R. exulans, Mus musculus). Biol. Invasions 15, 1037–1048 (2013).Article 

    Google Scholar 
    2.Gulka, J. et al. Dietary niche shifts of multiple marine predators under varying prey availability on the northeast Newfoundland coast. Front. Mar. Sci. 4, 324 (2017).Article 

    Google Scholar 
    3.Davey, C. M., Chamberlain, D. E., Newson, S. E., Noble, D. G. & Johnston, A. Rise of the generalists: Evidence for climate driven homogenization in avian communities. Glob. Ecol. Biogeogr. 21, 568–578 (2012).Article 

    Google Scholar 
    4.Wilby, A. & Thomas, M. B. Natural enemy diversity and pest control: Patterns of pest emergence with agricultural intensification. Ecol. Lett. 5, 353–360 (2002).Article 

    Google Scholar 
    5.Ducatez, S., Sol, D., Sayol, F. & Lefebvre, L. Behavioural plasticity is associated with reduced extinction risk in birds. Nat. Ecol. Evol. 4, 788–793 (2020).Article 

    Google Scholar 
    6.Gould, J. Description of new species of finches collected by Darwin in the Galapagos. In Vol. 5, pp. 4–7 (1837).7.Jung, K. & Kalko, E. K. Where forest meets urbanization: Foraging plasticity of aerial insectivorous bats in an anthropogenically altered environment. J. Mammal. 91, 144–153 (2010).Article 

    Google Scholar 
    8.Manenti, R., Denoël, M. & Ficetola, G. F. Foraging plasticity favours adaptation to new habitats in fire salamanders. Anim. Behav. 86, 375–382 (2013).Article 

    Google Scholar 
    9.Amato, K. R. et al. Evolutionary trends in host physiology outweigh dietary niche in structuring primate gut microbiomes. ISME J. 13, 576–587 (2019).CAS 
    Article 

    Google Scholar 
    10.Schlomann, B. H. & Parthasarathy, R. Timescales of gut microbiome dynamics. Curr. Opin. Microbiol. 50, 56–63 (2019).Article 

    Google Scholar 
    11.Legal, L., Chappe, B. & Jallon, J. M. Molecular basis of Morinda citrifolia (L.): Toxicity on drosophila. J. Chem. Ecol. 20, 1931–1943 (1994).CAS 
    Article 

    Google Scholar 
    12.R’kha, S., Capy, P. & David, J. R. Host-plant specialization in the Drosophila melanogaster species complex: A physiological, behavioral, and genetical analysis. Proc. Natl. Acad. Sci. 88, 1835–1839 (1991).ADS 
    Article 

    Google Scholar 
    13.Chandler, J. A., Lang, J. M., Bhatnagar, S., Eisen, J. A. & Kopp, A. Bacterial communities of diverse Drosophila species: Ecological context of a host–microbe model system. PLoS Genet. 7, e1002272 (2011).CAS 
    Article 

    Google Scholar 
    14.Storelli, G. et al. Lactobacillus plantarum promotes Drosophila systemic growth by modulating hormonal signals through TOR-dependent nutrient sensing. Cell Metab. 14, 403–414 (2011).CAS 
    Article 

    Google Scholar 
    15.Ryu, J.-H. et al. Innate immune homeostasis by the homeobox gene caudal and commensal-gut mutualism in Drosophila. Science 319, 777–782 (2008).ADS 
    CAS 
    Article 

    Google Scholar 
    16.Nishida, A. H. & Ochman, H. Rates of gut microbiome divergence in mammals. Mol. Ecol. 27, 1884–1897 (2018).Article 

    Google Scholar 
    17.Ochman, H. et al. Evolutionary relationships of wild hominids recapitulated by gut microbial communities. PLoS Biol. 8, e1000546 (2010).Article 

    Google Scholar 
    18.Gomez, A. et al. Plasticity in the human gut microbiome defies evolutionary constraints. MSphere 4, e00271-e319 (2019).Article 

    Google Scholar 
    19.Chen, C.-Y., Chen, P.-C., Weng, F.C.-H., Shaw, G.T.-W. & Wang, D. Habitat and indigenous gut microbes contribute to the plasticity of gut microbiome in oriental river prawn during rapid environmental change. PLoS ONE 12, e0181427 (2017).Article 

    Google Scholar 
    20.Vijendravarma, R. K., Narasimha, S. & Kawecki, T. J. Predatory cannibalism in Drosophila melanogaster larvae. Nat. Commun. 4, 1–8 (2013).Article 

    Google Scholar 
    21.Fisher, A. M. et al. Relatedness modulates density-dependent cannibalism rates in Drosophila. In review.22.Amlou, M., Moreteau, B. & David, J. Genetic analysis of Drosophila sechellia specialization: Oviposition behavior toward the major aliphatic acids of its host plant. Behav. Genet. 28, 455–464 (1998).CAS 
    Article 

    Google Scholar 
    23.Early, A. M., Shanmugarajah, N., Buchon, N. & Clark, A. G. Drosophila genotype influences commensal bacterial levels. PLoS ONE 12, e0170332 (2017).Article 

    Google Scholar 
    24.Alcock, J., Maley, C. C. & Aktipis, C. A. Is eating behavior manipulated by the gastrointestinal microbiota? Evolutionary pressures and potential mechanisms. BioEssays 36, 940–949 (2014).Article 

    Google Scholar 
    25.Lizé, A. & Lewis, Z. The microbiome and host behaviour. In Microbiomes of Soils, Plants and Animals: An Integrated Approach (Eds. Antwis, R. E. et al.) 98–121 (Cambridge University Press, 2020).26.Wong, A.C.-N. et al. Gut microbiota modifies olfactory-guided microbial preferences and foraging decisions in Drosophila. Curr. Biol. 27, 2397–2404 (2017).CAS 
    Article 

    Google Scholar 
    27.Hulme, P. E. Climate change and biological invasions: Evidence, expectations, and response options. Biol. Rev. 92, 1297–1313 (2017).Article 

    Google Scholar 
    28.Han, B. A., Kramer, A. M. & Drake, J. M. Global patterns of zoonotic disease in mammals. Trends Parasitol. 32, 565–577 (2016).Article 

    Google Scholar 
    29.Gibb, R. et al. Zoonotic host diversity increases in human-dominated ecosystems. Nature 584, 398–402 (2020).ADS 
    CAS 
    Article 

    Google Scholar 
    30.Bertani, G. Lysogeny at mid-twentieth century: P1, P2, and other experimental systems. J. Bacteriol. 186, 595–600 (2004).CAS 
    Article 

    Google Scholar 
    31.Atlas, R. M. Handbook of microbiological media (CRC Press, Boca Raton, 2010).Book 

    Google Scholar 
    32.Heys, C. et al. The effect of gut microbiota elimination in Drosophila melanogaster: A how-to guide for host–microbiota studies. Ecol. Evol. 8, 4150–4161 (2018).Article 

    Google Scholar 
    33.Altschul, S. F., Gish, W., Miller, W., Myers, E. W. & Lipman, D. J. Basic local alignment search tool. J. Mol. Biol. 215, 403–410 (1990).CAS 
    Article 

    Google Scholar 
    34.Dekker, T., Ibba, I., Siju, K., Stensmyr, M. C. & Hansson, B. S. Olfactory shifts parallel superspecialism for toxic fruit in Drosophila melanogaster sibling, D. sechellia. Curr. Biol. 16, 101–109 (2006).CAS 
    Article 

    Google Scholar 
    35.Arnold, T. W. Uninformative parameters and model selection using Akaike’s information criterion. J. Wildl. Manag. 74, 1175–1178 (2010).Article 

    Google Scholar 
    36.R Core Team. R: A language and environment for statistical computing. (R Foundation for Statistical Computing, Vienna, Austria, 2019).37.Bates, D., Sarkar, D., Bates, M. D. & Matrix, L. The lme4 package. R Package Version 2, 74 (2007).
    Google Scholar 
    38.Kuznetsova, A., Brockhoff, P. B. & Christensen, R. H. lmerTest package: Tests in linear mixed effects models. J. Stat. Softw. 82, 1–26 (2017).Article 

    Google Scholar  More

  • in

    Diversity, prevalence, and expression of cyanase genes (cynS) in planktonic marine microorganisms

    1.Nowakowska M, Sterzel M, Szczubiałka K. Photosensitized oxidation of cyanide in aqueous solutions of photoactive modified hydroxyethylcellulose. J Polym Environ. 2006;14:59–64.CAS 
    Article 

    Google Scholar 
    2.Kamennaya NA, Chernihovsky M, Post AF. The cyanate utilization capacity of marine unicellular Cyanobacteria. Limnol Oceanogr. 2008;53:2485–94.CAS 
    Article 

    Google Scholar 
    3.Palatinszky M, Herbold C, Jehmlich N, Pogoda M, Han P, von Bergen M, et al. Cyanate as an energy source for nitrifiers. Nature. 2015;524:105–8.CAS 
    Article 

    Google Scholar 
    4.Mooshammer M, Wanek W, Jones SH, Richter A, Wagner M. Cyanate–a low abundant but actively cycled nitrogen compound in soil. https://www.biorxiv.org/content/10.1101/2020.07.12.199737v1.full. 2020.5.Linder T. Cyanase-independent utilization of cyanate as a nitrogen source in ascomycete yeasts. World J Micro Biot. 2019;35:1–7.CAS 
    Article 

    Google Scholar 
    6.Widner B, Fuchsman CA, Chang BX, Rocap G, Mulholland MR. Utilization of urea and cyanate in waters overlying and within the eastern tropical north Pacific oxygen deficient zone. FEMS Microbiol Ecol. 2018;94:fiy138.CAS 
    Article 

    Google Scholar 
    7.Widner B, Mulholland MR, Mopper K. Distribution, sources, and sinks of cyanate in the coastal North Atlantic Ocean. Environ Sci Tech Let. 2016;3:297–302.CAS 
    Article 

    Google Scholar 
    8.Widner B, Mulholland MR, Mopper K. Chromatographic determination of nanomolar cyanate concentrations in estuarine and sea waters by precolumn fluorescence derivatization. Anal Chem. 2013;85:6661–6.CAS 
    Article 

    Google Scholar 
    9.Widner B, Mordy CW, Mulholland MR. Cyanate distribution and uptake above and within the Eastern Tropical South Pacific oxygen deficient zone. Limnol Oceanogr. 2018;63:S177–S192.CAS 
    Article 

    Google Scholar 
    10.Kuypers MMM, Marchant HK, Kartal B. The microbial nitrogen-cycling network. Nat Rev Microbiol. 2018;16:263.CAS 
    Article 

    Google Scholar 
    11.Smith SR, Dupont CL, McCarthy JK, Broddrick JT, Oborník M, Horák A, et al. Evolution and regulation of nitrogen flux through compartmentalized metabolic networks in a marine diatom. Nat Commun. 2019;10:1–14.Article 

    Google Scholar 
    12.Allen JrCM, Jones ME. Decomposition of carbamylphosphate in aqueous solutions. Biochemistry. 1964;3:1238–47.CAS 
    Article 

    Google Scholar 
    13.Kamenaya NA, Post AF. Characterization of cyanate metabolism in marine Synechococcus and Prochlorococcus spp. Appl Enviro Micro. 2011;77:291–301.Article 

    Google Scholar 
    14.Kamennaya NA, Post AF. Distribution and expression of the cyanate acquisition potential among cyanobacterial populations in oligotrophic marine waters. Limnol Oceanogr. 2013;58:1959–71.CAS 
    Article 

    Google Scholar 
    15.Kitzinger K, Padilla CC, Marchant HK, Hach PF, Herbold CW, Kidane AT, et al. Cyanate and urea are substrates for nitrification by Thaumarchaeota in the marine environment. Nat Microbiol. 2019;4:234–43.CAS 
    Article 

    Google Scholar 
    16.Pachiadaki MG, Sintes E, Bergauer K, Brown JM, Record NR, Swan BK, et al. Major role of nitrite-oxidizing bacteria in dark ocean carbon fixation. Science. 2017;358:1046–51.CAS 
    Article 

    Google Scholar 
    17.Ganesh S, Bertagnolli AD, Bristow LA, Padilla CC, Blackwood N, Aldunate M, et al. Single cell genomic and transcriptomic evidence for the use of alternative nitrogen substrates by anammox bacteria. ISME J. 2018;12:2706–22.CAS 
    Article 

    Google Scholar 
    18.Johnson WV, Anderson PM. Bicarbonate is a recycling substrate for cyanase. J Biol Chem. 1987;262:9021–5.CAS 
    Article 

    Google Scholar 
    19.Miller AG, Espie GS. Photosynthetic metabolism of cyanate by the cyanobacterium Synechococcus UTEX 625. Arch Microbiol. 1994;162:151–7.CAS 
    Article 

    Google Scholar 
    20.Harano Y, Suzuki I, Maeda S, Kaneko T, Tabata S, Omata T. Identification and nitrogen regulation of the cyanase gene from the cyanobacteria Synechocystis sp. strain PCC 6803 and Synechococcus sp. strain PCC 7942. J Bacteriol. 1997;179:5744.CAS 
    Article 

    Google Scholar 
    21.Sung YC, Anderson PM, Fuchs JA. Characterization of high-level expression and sequencing of the Escherichia coli K-12 cynS gene encoding cyanase. J Bacteriol. 1987;169:5224.CAS 
    Article 

    Google Scholar 
    22.Sáez LP, Cabello P, Ibáñez MI, Luque-Almagro VM, Roldán MD, Moreno-Vivián C. Cyanate assimilation by the alkaliphilic cyanide-degrading bacterium Pseudomonas pseudoalcaligenes CECT5344: mutational analysis of the cyn gene cluster. Int J Mol Sci. 2019;20:3008.Article 

    Google Scholar 
    23.Wood AP, Kelly DP, McDonald IR, Jordan SL, Morgan TD, Khan S, et al. A novel pink-pigmented facultative methylotroph, Methylobacterium thiocyanatum sp. nov., capable of growth on thiocyanate or cyanate as sole nitrogen sources. Arch Microbiol. 1998;169:148–58.CAS 
    Article 

    Google Scholar 
    24.Elleuche S, Pöggeler S. A cyanase is transcriptionally regulated by arginine and involved in cyanate decomposition in Sordaria macrospora. Fungal Genet Biol. 2008;45:1458–69.CAS 
    Article 

    Google Scholar 
    25.Schlachter CR, Klapper V, Wybouw N, Radford T, Van Leeuwen T, Grbic M, et al. Structural characterization of a eukaryotic cyanase from Tetranychus urticae. J Agr Food Chem. 2017;65:5453–62.CAS 
    Article 

    Google Scholar 
    26.Qian D, Jiang L, Lu L, Wei C, Li Y. Biochemical and structural properties of cyanases from Arabidopsis thaliana and Oryza sativa. PLoS One. 2011;6:e18300.CAS 
    Article 

    Google Scholar 
    27.Zarlenga DS, Mitreva M, Thompson P, Tyagi R, Tuo W, Hoberg EP. A tale of three kingdoms: members of the Phylum Nematoda independently acquired the detoxifying enzyme cyanase through horizontal gene transfer from plants and bacteria. Parasitology. 2019;146:445–52.CAS 
    Article 

    Google Scholar 
    28.Ranjan B, Choi PH, Pillai S, Permaul K, Tong L, Singh S. Crystal structure of a thermophilic fungal cyanase and its implications on the catalytic mechanism for bioremediation. Sci Rep. 2021;11:1–10.Article 

    Google Scholar 
    29.Villar E, Vannier T, Vernette C, Lescot M, Cuenca M, Alexandre A, et al. The Ocean Gene Atlas: exploring the biogeography of plankton genes online. Nucleic Acids Res. 2018;46:W289–W295.CAS 
    Article 

    Google Scholar 
    30.Walsh MA, Otwinowski Z, Perrakis A, Anderson PM, Joachimiak A. Structure of cyanase reveals that a novel dimeric and decameric arrangement of subunits is required for formation of the enzyme active site. Structure. 2000;8:505–14.CAS 
    Article 

    Google Scholar 
    31.Butryn A, Stoehr G, Linke-Winnebeck C, Hopfner KP. Serendipitous crystallization and structure determination of cyanase (CynS) from Serratia proteamaculans. Acta Crystallogr F. 2015;71:471–6.CAS 
    Article 

    Google Scholar 
    32.Pederzoli R, Tarantino D, Gourlay LJ, Chaves-Sanjuan A, Bolognesi M. Detecting the nature and solving the crystal structure of a contaminant protein from an opportunistic pathogen. Acta Crystallogr F. 2020;76:392–7.CAS 
    Article 

    Google Scholar 
    33.Wybouw N, Balabanidou V, Ballhorn DJ, Dermauw W, Grbić M, Vontas J, et al. A horizontally transferred cyanase gene in the spider mite Tetranychus urticae is involved in cyanate metabolism and is differentially expressed upon host plant change. Insect Biochem Molec. 2012;42:881–9.CAS 
    Article 

    Google Scholar 
    34.Spang A, Poehlein A, Offre P, Zumbrägel S, Haider S, Rychlik N, et al. The genome of the ammonia‐oxidizing candidatus nitrososphaera gargensis: insights into metabolic versatility and environmental adaptations. Environ Microbiol. 2012;14:3122–45.CAS 
    Article 

    Google Scholar 
    35.Palomo A, Pedersen AG, Fowler SJ, Dechesne A, Sicheritz-Pontén T, Smets BF. Comparative genomics sheds light on niche differentiation and the evolutionary history of comammox Nitrospira. ISMEJ. 2018;12:1779–93.Article 

    Google Scholar  More

  • in

    Late Pleistocene human paleoecology in the highland savanna ecosystem of mainland Southeast Asia

    1.Roberts, P. & Stewart, B. A. Defining the ‘generalist specialist’ niche for Pleistocene Homo sapiens. Nat. Hum. Behav. 2, 542–550 (2018).PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    2.Heaney, L. R. A synopsis of climatic and vegetational change in Southeast Asia. Clim. Change 19, 53–61 (1991).ADS 
    Article 

    Google Scholar 
    3.Morley, R. J. Origin and Evolution of Tropical Rain Forests (Wiley, 2000).
    Google Scholar 
    4.Bird, M. I., Taylor, D. & Hunt, C. Palaeoenvironments of insular Southeast Asia during the last Glacial Period: a savanna corridor in Sundaland?. Quat. Sci. Rev. 24, 2228–2242 (2005).ADS 
    Article 

    Google Scholar 
    5.Wurster, C. M., Rifai, H., Zhou, B., Haig, J. & Bird, M. I. Savanna in equatorial Borneo during the late Pleistocene. Sci. Rep. 9, 6392. https://doi.org/10.1038/s41598-019-42670-4 (2019).ADS 
    CAS 
    Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    6.Wurster, C. M. & Bird, M. I. Barriers and bridges: early human dispersals in equatorial SE Asia. Geol. Soc. Spec. Publ. 411, 235–250 (2016).ADS 
    Article 

    Google Scholar 
    7.Zaim, Y. Geological evidence for the earliest appearance of hominins in Indonesia. In Out of Africa I: The First Hominin Colonization of Eurasia (eds Fleagle, J. G. et al.) 97–110 (Springer, 2010).Chapter 

    Google Scholar 
    8.Cannon, C. H., Morley, R. J. & Bush, A. B. G. The current refugial rainforests of Sundaland are unrepresentative of their biogeographic past and highly vulnerable to disturbance. Proc. Natl. Acad. Sci. USA 106, 11188–11193 (2009).ADS 
    CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    9.Raes, N. et al. Historical distribution of Sundaland’s Dipterocarp rainforests at Quaternary glacial maxima. Proc. Natl. Acad. Sci. USA 111, 16790–16795 (2014).ADS 
    CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    10.Suraprasit, K., Jongautchariyakul, S., Yamee, C., Pothichaiya, C. & Bocherens, H. New fossil and isotope evidence for the Pleistocene zoogeographic transition and hypothesized savanna corridor in peninsular Thailand. Quat. Sci. Rev. 221, 1055861 (2019).Article 

    Google Scholar 
    11.Pookajorn, S. Human activities and environmental changes during the late pleistocene to middle holocene in Southern Thailand and Southeast Asia. In Humans at the End of the Ice Age: The Archaeology of the Pleistocene—Holocene Transition, Interdisciplinary Contributions to Archaeology (eds Straus, L. G. et al.) 201–213 ( Springer, 1996).Chapter 

    Google Scholar 
    12.Schepartz, L. A., Miller-Antonio, S. & Bakken, D. A. Upland resources and the early palaeolithic occupation of Southern China, Vietnam, Laos Thailand and Burma. World Archaeol. 32, 1–13 (2000).Article 

    Google Scholar 
    13.Mudar, K. & Anderson, D. New evidence for Southeast Asian pleistocene foraging economies: faunal remains from the early levels of Lang Rongrien Rockshelter, Krabi, Thailand. Asian Perspect. 46, 298–334 (2007).Article 

    Google Scholar 
    14.Shoocongdej, R. Late Pleistocene activities at the Tham Lod rockshelter in Highland Pang Mapha, Mae Hong Son province, Norhwestern Thailand. In Uncovering Southeast Asia’s Past (eds Bacus, E. et al.) 22–37 (NUS Press, 2006).
    Google Scholar 
    15.Shoocongdej, R. et al. Final report of Highland Archaeology Project in Pang Mapha District, Mae Hong Son Province Phase 2, Vol. 2 (Thailand Research Fund, 2007).16.Demeter, F. et al. Anatomically modern human in Southeast Asia (Laos) by 46 ka. Proc. Natl. Acad. Sci. USA 109, 14375–14380 (2012).ADS 
    CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    17Demeter, F. et al. Early modern humans and morphological variation in Southeast Asia: fossil evidence from Tam Pa Ling. Laos. PLoS ONE 10, e0121193. https://doi.org/10.1371/journal.pone.0121193 (2015).CAS 
    Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    18.Viet, N. First archaeological evidence of symbolic activities from the Pleistocene of Vietnam. In Emergence and Diversity of Human Behavior Paleolithic Asia (ed. Kaifu, Y.) 133–139 (Texas A&M University Press, 2015).
    Google Scholar 
    19.Higham, C. F. & Thosarat, R. An early hunter-gatherer site at Ban Non Wat, Northeast Thailand. J. Indo. Pacif. Archaeol. 43, 93–96 (2019).Article 

    Google Scholar 
    20.Gorman, C. F. Excavations at Spirit Cave, North Thailand: Some Interim Interpretations. Asian Perspect. 13, 79–107 (1970).
    Google Scholar 
    21.Tayles, N., Halcrow, S. E., Sayavongkhamdy, T. & Souksavatdy, V. A prehistoric flexed human burial from Pha Phen, Middle Mekong Valley, Laos: its context in Southeast Asia. Anthropol. Sci. 123, 1–12 (2015).Article 

    Google Scholar 
    22.Conrad, C., Higham, C., Eda, M. & Marwick, B. Palaeoecology and forager subsistence strategies during the Pleistocene—Holocene transition: A reinvestigation of the zooarchaeological assemblage from Spirit Cave, Mae Hong Son Province, Thailand. Asian Perspect. 5, 2–27 (2016).Article 

    Google Scholar 
    23.Zeitoun, V. D. et al. Discovery of an outstanding Hoabinhian site from the Late Pleistocene at Doi Pha Kan (Lampang province, northern Thailand). Archaeol. Res. Asia 18, 1–16 (2019).Article 

    Google Scholar 
    24.Shoocongdej, R. Forager mobility organization in seasonal tropical environments of western Thailand. World Archaeol. 32, 14–40 (2000).Article 

    Google Scholar 
    25.Forestier, H. et al. The Hoabinhian from Laang Spean Cave in its stratigraphic, chronological, typo-technological and environmental context (Cambodia, Battambang province). J. Archaeol. Sci. Rep. 3, 194–206 (2015).
    Google Scholar 
    26.Chitkament, T., Gaillard, C. & Shoocongdej, R. Tham Lod rockshelter (Pang Mapha district, north-western Thailand): Evolution of the lithic assemblages during the late Pleistocene. Quat. Int. 416, 151–161 (2016).Article 

    Google Scholar 
    27.Marwick, B. The Hoabinhian of Southeast Asia and its relationship to regional Pleistocene lithic technologies. In Lithic Technological Organization and Paleoenvironmental Change Global and Diachronic Perspectives (eds Robinson, E. & Sellet, F.) 63–78 (Springer, 2018).Chapter 

    Google Scholar 
    28.Marwick, B. & Gagan, M. K. Late Pleistocene monsoon variability in northwest Thailand: an oxygen isotope sequence from the bivalve Margaritanopsis laosensis excavated in Mae Hong Son province. Quat. Sci. Rev. 30, 3088–3098 (2011).ADS 
    Article 

    Google Scholar 
    29.Marwick, B. Multiple Optima in Hoabinhian flaked stone artefact palaeoeconomics and palaeoecology at two archaeological sites in Northwest Thailand. J. Anthropol. Archaeol. 32, 553–564 (2013).Article 

    Google Scholar 
    30.Wattanapituksakul, A., Filoux, A., Amphansri, A. & Tumpeesuwan, S. Late Pleistocene Caprinae assemblages of Tham Lod Rockshelter (Mae Hong Son Province, Northwest Thailand). Quat. Int. 493, 212–226 (2018).Article 

    Google Scholar 
    31.Shoocongdej, R. & Wattanapituksakul, A. Faunal assemblages and demography during the Late Pleistocene (MIS 2–1) to Early Holocene in Highland Pang Mapha, Northwest Thailand. Quat. Int. 563, 51–63 (2020).Article 

    Google Scholar 
    32.DeNiro, M. J. & Epstein, S. Influence of diet on the distribution of carbon isotopes in animals. Geochim. Cosmochim. Acta 42, 495–506 (1978).ADS 
    CAS 
    Article 

    Google Scholar 
    33.Van Der Merwe, N. J. & Vogel, J. C. 13C Content of human collagen as a measure of prehistoric diet in woodland North America. Nature 276, 815–816 (1978).ADS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    34.Cerling, T. E. & Harris, J. M. Carbon isotope fractionation between diet and bioapatite in ungulate mammals and implications for ecological and paleoecological studies. Oecologia 120, 347–363 (1999).ADS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    35.Cerling, T. E., Hart, J. A. & Hart, T. B. Stable isotope ecology in the Ituri Forest. Oecologia 138, 5–12 (2004).ADS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    36.Bourgon, N. et al. Zinc isotopes in Late Pleistocene fossil teeth from a Southeast Asian cave setting preserve paleodietary information. Proc. Natl. Acad. Sci. USA 117, 4675–4681 (2020).CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    37.van Klinken, G. J. Bone Collagen quality indicators for palaeodietary and radiocarbon measurements. J. Archaeol. Sci. 26, 687–695 (1999).Article 

    Google Scholar 
    38.Pestle, W. J. & Colvard, M. Bone collagen preservation in the tropics: a case study from ancient Puerto Rico. J. Archaeol. Sci. 39, 2079–2090 (2012).CAS 
    Article 

    Google Scholar 
    39.Ecker, M. et al. Middle Pleistocene ecology and Neanderthal subsistence: Insights from stable isotope analyses in Payre (Ardèche, southeastern France). J. Hum. Evol. 65, 363–373 (2013).PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    40Kohn, M. & Cerling, T. E. Stable isotope compositions of biological apatite. In Phosphates—Geochemical Geobiological and Materials Importance Reviews in Mineralogy and Geochemistry Vol. 48 (eds Kohn, M. et al.) 455–488 (Mineralogical Society of America, 2002).Chapter 

    Google Scholar 
    41.Biasatti, D., Wang, Y., Gao, F., Xu, Y. & Flynn, L. Paleoecologies and paleoclimates of late cenozoic mammals from Southwest China: evidence from stable carbon and oxygen isotopes. J. Asian Earth Sci. 44, 48–61 (2012).ADS 
    Article 

    Google Scholar 
    42.Clementz, M. T., Fox-Dobbs, K., Wheatley, P.-V., Koch, P. L. & Doak, D. F. Revisiting old bones: coupled carbon isotope analysis of bioapatite and collagen as an ecological and palaeoecological tool. Geol. J. 44, 605–620 (2009).CAS 
    Article 

    Google Scholar 
    43.Domingo, M. S., Domingo, L., Badgley, C., Sanisidro, O. & Morales, J. Resource partitioning among top predators in a Miocene food web. Proc. R. Soc. B 280, 20122138. https://doi.org/10.1098/rspb.2012.2138 (2013).Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    44.Codron, D., Clauss, M., Codron, J. & Tütken, T. Within trophic level shifts in collagen–carbonate stable carbon isotope spacing are propagated by diet and digestive physiology in large mammal herbivores. Ecol. Evol. 8, 3983–3995 (2018).PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    45Tejada-Lara, J. V. et al. Body mass predicts isotope enrichment in herbivorous mammals. Proc. R. Soc. B 285, 20181020. https://doi.org/10.1098/rspb.2018.1020 (2018).CAS 
    Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    46.Cerling, T. E. et al. Stable isotope-based diet reconstructions of Turkana Basin hominins. Proc. Natl. Acad. Sci. USA 110, 10501–10506 (2013).ADS 
    CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    47.Ayliffe, L. K. & Chivas, A. R. Oxygen isotope composition of the bone phosphate of Australian kangaroos: potential as a palaeoenvironmental recorder. Geochim. Cosmochim. Acta 54, 2603–2609 (1990).ADS 
    CAS 
    Article 

    Google Scholar 
    48.Levin, N. E., Cerling, T. E., Passey, B. H., Harris, J. M. & Ehleringer, J. R. A stable isotope aridity index for terrestrial environments. Proc. Natl. Acad. Sci. USA 103, 11201–11205 (2006).ADS 
    CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    49.Bocherens, H., Koch, P., Mariotti, A., Geraads, D. & Jaeger, J.-J. Isotopic biogeochemistry (13C, 18O) of mammalian enamel from African Pleistocene hominoid sites. Palaios 11, 306–308 (1996).ADS 
    Article 

    Google Scholar 
    50.Hambali, K., Ismail, A., Md-Zain, B. M., Amir, A. & Karim, F. A. Diet of long-tailed macaques (Macaca fascicularis) at the entrance of Kuala Selangor Nature Park (anthropogenic habitat): food selection that leads to human-macaque conflict. Acta Biol. Malay. 3, 58–68 (2014).
    Google Scholar 
    51.Nila, S., Suryobroto, B. & Widayati, K. A. Dietary variation of long tailed macaques (Macaca fascicularis) in Telaga Warna, Bogor, West Java. HAYATI J. Biosci. 21, 8–14 (2014).Article 

    Google Scholar 
    52.Lekagul, B. & McNeely, J. A. Mammals of Thailand: Association for the Conservation of Wildlife (Kurusapa Ladproa Press, 1988).
    Google Scholar 
    53.Suraprasit, K., Bocherens, H., Chaimanee, Y., Panha, S. & Jaeger, J.-J. Late Middle Pleistocene ecology and climate in Northeastern Thailand inferred from the stable isotope analysis of Khok Sung herbivore tooth enamel and the land mammal cenogram. Quat. Sci. Rev. 193, 24–42 (2018).ADS 
    Article 

    Google Scholar 
    54Suraprasit, K. et al. Long-term isotope evidence on the diet and habitat breadth of pleistocene to holocene caprines in Thailand: implications for the extirpation and conservation of Himalayan Gorals. Front. Ecol. Evol. 8, 67. https://doi.org/10.3389/fevo.2020.00067 (2020).Article 

    Google Scholar 
    55.Kohn, M. J. Predicting animal δ18O: Accounting for diet and physiological adaptation. Geochim. Cosmochim. Acta 60, 4811–4829 (1996).ADS 
    CAS 
    Article 

    Google Scholar 
    56.Kohn, M. J., Schoeninger, M. J. & Valley, J. W. Herbivore tooth oxygen isotope compositions: effects of diet and physiology. Geochim. Cosmochim. Acta 60, 3889–3896 (1996).ADS 
    CAS 
    Article 

    Google Scholar 
    57.Dunbar, J. & Wilson, T. Oxygen and hydrogen isotopes in fruits and vegetable juices. Plant Physiol. 72, 725–727 (1983).CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    58.Yakir, D. Variations in the natural abundances of oxygen-18 and deuterium in plant carbohydrates. Plant Cell Environ. 15, 1005–1020 (1992).CAS 
    Article 

    Google Scholar 
    59.Fricke, H. C. & O’Neil, J. R. Inter- and intra-tooth variation in the oxygen isotope composition of mammalian tooth enamel phosphate: implications for palaeoclimatological and palaeobiological research. Palaeogeogr. Palaeoclimatol. Palaeoecol. 126, 91–99 (1996).Article 

    Google Scholar 
    60.Fricke, H. C., Clyde, W. C. & O’Neil, J. R. Intra-tooth variations in δ18O (PO4) of mammalian tooth enamel as a record of seasonal variations in continental climate variables. Geochem. Cosmochim. Acta 62, 1839–1850 (1998).ADS 
    CAS 
    Article 

    Google Scholar 
    61.Balasse, M., Ambrose, S. H., Smith, A. B. & Price, T. D. The seasonal mobility model for prehistoric herders in the south-western Cape of South Africa assessed by isotopic analysis of sheep tooth enamel. J. Archaeol. Sci. 29, 917–932 (2002).Article 

    Google Scholar 
    62Ratnam, J., Tomlinson, K. W., Rasquinha, D. N. & Sankaran, M. Savannahs of Asia: antiquity, biogeography, and an uncertain future. Philos. Trans. R. Soc. Lond. B Biol. Sci. 371, 2015305. https://doi.org/10.1098/rstb.2015.0305 (2016).CAS 
    Article 

    Google Scholar 
    63.Pushkina, D., Bocherens, H., Chaimanee, Y. & Jaeger, J.-J. Stable carbon isotope reconstructions of diet and paleoenvironment from the late middle Pleistocene Snake Cave in Northeastern Thailand. Naturwissenschaften 97, 299–309 (2010).ADS 
    CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    64.Louys, J. & Roberts, P. Environmental drivers of megafauna and hominin extinction in Southeast Asia. Nature 586, 402–406 (2020).ADS 
    CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    65.Passey, B. H. et al. Carbon isotope fractionation between diet, breath CO2, and bioapatite in different mammals. J. Archaeol. Sci. 32, 1459–1470 (2005).Article 

    Google Scholar 
    66.Dutt, S. et al. Abrupt changes in Indian summer monsoon strength during 33,800 to 5500 years B.P. Geophys. Res. Lett. 42, 5526–5532 (2015).ADS 
    Article 

    Google Scholar 
    67.Ronay, E. R., Breitenbach, S. F. M. & Oster, J. L. Sensitivity of speleothem records in the Indian Summer Monsoon region to dry season infiltration. Sci. Rep. 9, 5091. https://doi.org/10.1038/s41598-019-41630-2 (2019).ADS 
    CAS 
    Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    68Liu, G. et al. On the glacial-interglacial variability of the Asian monsoon in speleothem δ18O records. Sci. Adv. 6, 8eaay8189. https://doi.org/10.1126/sciadv.aay8189 (2020).CAS 
    Article 

    Google Scholar 
    69.Lambeck, K., Rouby, H., Purcell, A., Sun, Y. & Sambridge, M. Sea level and global ice volumes from the Last Glacial Maximum to the Holocene. Proc. Natl. Acad. Sci. USA 111, 15296–15303 (2014).ADS 
    CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    70Rabett, R. J. Human Adaptation in the Asian Palaeolithic: hominin dispersal and behaviour during the late quaternary (Cambridge University Press, 2012).Book 

    Google Scholar 
    71.Bailey, R. C. et al. Hunting and gathering in tropical rain forest: Is it possible?. Am. Anthropol. 91, 59–82 (1989).Article 

    Google Scholar 
    72.Mercader, J. Forest people: the role of African rainforests in human evolution and dispersal. Evol. Anthropol. 11, 117–124 (2002).Article 

    Google Scholar 
    73.Mercader, J. Under the Canopy: The Archaeology of Tropical Rainforests (Rutgers University Press, 2002).
    Google Scholar 
    74.Mercader, J. Foragers of the Congo: the early settlement of the Ituri forest. In Under the Canopy: The Archeology of Tropical Rain Forests (ed. Mercader, J.) 93–116 (Rutgers University Press, London, 2003).
    Google Scholar 
    75.Perera, N. et al. People of the ancient rainforest: Late Pleistocene foragers at the Batadomba-lena rockshelter, Sri Lanka. J. Hum. Evol. 61, 254–269 (2011).PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    76.Roberts, P. et al. Direct evidence for human reliance on rainforest resources in late Pleistocene Sri Lanka. Science 347, 1246–1249 (2015).ADS 
    CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    77.Roberts, P. et al. Fruits of the forest: human stable isotope ecology and rainforest adaptations in Late Pleistocene and Holocene (~36 to 3 ka) Sri Lanka. J. Hum. Evol. 106, 102–118 (2017).PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    78Wedage, O. et al. Specialized rainforest hunting by Homo sapiens ~45,000 years ago. Nat. Commun. 10, 739. https://doi.org/10.1038/s41467-019-08623-1 (2019).CAS 
    Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    79.Ji, X. et al. The oldest Hoabinhian technocomplex in Asia (43.5 ka) at Xiaodong rockshelter, Yunnan Province, southwest China. Quat. Int. 400, 166–174 (2016).Article 

    Google Scholar 
    80.Olsen, J. W. & Ciochon, R. L. A review of evidence for postulated Middle Pleistocene occupations in Viet Nam. J. Hum. Evol. 19, 761–788 (1990).Article 

    Google Scholar 
    81.Rabett, R. et al. The Tràng An Project: Late-to-Post-Pleistocene Settlement of the Lower Song Hong Valley, North Vietnam. J. R. Asiat. Soc. 19, 83–109 (2009).Article 

    Google Scholar 
    82.Rabett, R. et al. Tropical limestone forest resilience and late Pleistocene foraging during MIS-2 in the Tràng An massif, Vietnam. Quat. Int. 448, 62–81 (2017).Article 

    Google Scholar 
    83.Barker, G. et al. The ‘Human Revolution’ in lowland tropical Southeast Asia: the antiquity and behavior of anatomically modern humans at Niah Cave (Sarawak, Borneo). J. Hum. Evol. 52, 243–261 (2007).PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    84.Piper, P. & Rabett, R. Hunting in a tropical rainforest: evidence from the terminal Pleistocene at Lobang Hangus, Niah Caves, Sarawak. Int. J. Osteoarchaeol. 19, 551–565 (2009).Article 

    Google Scholar 
    85.Hunt, C. O., Gilbertson, D. D. & Rushworth, G. A 50,000-year record of late Pleistocene tropical vegetation and human impact in lowland Borneo. Quat. Sci. Rev. 37, 61–80 (2012).ADS 
    Article 

    Google Scholar 
    86.de Vos, J. The Pongo faunas from Java and Sumatra and their significance for biostratigraphical and paleoecological interpretations. Proc. K. Ned. Akad. Wet. B. 86, 417–425 (1983).
    Google Scholar 
    87.Westaway, K. E. An early modern human presence in Sumatra 73000–63000 years ago. Nature 548, 322–325 (2017).ADS 
    CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    88.Storm, P. et al. Late Pleistocene Homo Sapiens in a tropical rainforest Fauna in East Java. J. Hum. Evol. 49, 536–545 (2005).PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    89.Storm, P. & de Vos, J. Rediscovery of the late Pleistocene Punung Hominin Sites and the Discovery of a New Site Gunung Dawung in East Java. Senck. Leth. 86, 271–281 (2006).Article 

    Google Scholar 
    90Roberts, P. et al. Isotopic evidence for initial coastal colonization and subsequent diversification in the human occupation of Wallacea. Nat. Commun. 11, 2068. https://doi.org/10.1038/s41467-020-15969-4 (2020).ADS 
    CAS 
    Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    91.Pasveer, J. M., Clarke, S. J. & Miller, G. H. Late Pleistocene human occupation of inland rainforest, Bird’s Head, Papua. Archaeol. Oceania 37, 92–95 (2002).Article 

    Google Scholar 
    92.Summerhayes, G. R. et al. Human adaptation and plant use in highland New Guinea 49,000 to 44,000 Years Ago. Science 330, 78–81 (2010).ADS 
    CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    93.Summerhayes, G. R., Field, J. H., Shaw, B. & Gaffney, D. The archaeology of forest exploitation and change in the tropics during the Pleistocene: the case of Northern Sahul (Pleistocene New Guinea). Quat. Int. 448, 14–30 (2017).Article 

    Google Scholar 
    94.Roberts, P., Gaffney, D., Lee-Thorp, J. A. & Summerhayes, G. R. Persistent tropical foraging in the highlands of terminal Pleistocene/Holocene New Guinea. Nature Ecol. Evol. 1, 1–6 (2017).CAS 
    Article 

    Google Scholar 
    95.Wedage, O. et al. Microliths in the South Asian rainforest ~45–4 ka: New insights from Fa-Hien Lena Cave, Sri Lanka. PLoS ONE https://doi.org/10.1371/journal.pone.0222606 (2019).Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    96.Bettis, E. A. et al. Way out of Africa: early Pleistocene paleoenvironments inhabited by Homo erectus in Sangiran, Java. J. Hum. Evol. 56, 11–24 (2009).PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    97.Brumm, A. et al. Age and context of the oldest known hominin fossils from Flores. Nature 534, 249–253 (2016).ADS 
    CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    98.Hammer, Ø., Harper, D. A. T. & Ryan, P. D. PAST: Paleontological statistics software package for education and data analysis. Palaeontol. Electron. 4, 1–9 (2001).
    Google Scholar  More