2018

2018 in review

The lab has been very busy this year and I wouldn't dare an attempt to summarize it all. In brief, we've put a lot of effort into documenting, predicting and understanding how tropical biodiversity will respond to global change. We've conducted and will continue to conduct research across the Asian and African tropics measuring and modelling species/community relationships with climate. Another major but more recent focus has been addressing wildlife trade. Of course, these drivers of extinction and ecological change continue to do their damage... we aim to minimize those threats and better manage them as best we can. With our recent work, I believe we have partially achieved this goal. But there is so much more to do! On-going and future work in the Global Change and Tropical Conservation lab will advance progress on research in climate change and wildlife trade. But we are also growing our efforts in topics such as urban ecology and humanities/social science-oriented conservation work. These will be points of emphasis in the lab in the coming years.

In personal news, I received tenure and was promoted to Associate Professor in October of this year. I'm so incredibly thankful for this and am excitedly looking ahead, eager to capitalize on this opportunity and responsibility. Wenda received his PhD and has moved across the hall to begin a postdoc with Louise Ashton. And Freda finished her MPhil and started a PhD at Princeton. Other students and postdocs in the lab continue to make excellent progress on their research.

Instead of listing all the papers to come out of the lab this year, I've decided to instead give background to some of our work and provide a few illustrations. Note that although all of the below were published this year, each took many years to mature:

How are Hong Kong moths responding to climate change?

Thanks to Roger's hard work and long-term monitoring of moths in Hong Kong, Wenda began analysing trends of moth elevation distribution changes early in his PhD. But as the title of his paper (just out this month) indicates, the patterns turned out to be quite complex. Morgan helped us eventually sort out signals from all the noise and we indeed found many lower range margin shifts following increasingly extreme weather events over the past decade. This paper represents one of a handful of studies highlighting species redistribution across elevation in the Asian tropics and specifically why documenting such impacts can be complicated by diverse communities experiencing variable climatic changes.

See paper in Diversity and Distributions

Does habitat change interact with climate to impact species redistribution?

Freda was several months into her MPhil research when we had a chat early one morning... most papers that document species elevational range shifts driven by climate change usually say that little habitat change occurred in the study period. Was this true? Even if habitat is protected, rarely is it possible for habitat to remain unchanged, especially for several decades. Freda then took a significant detour in her thesis and began studying this topic. Soon after, Jonathan joined us to provide much needed guidance on stats and mountains. By looking at lots of papers on elevational species redistribution, Freda found clear interactive effects of forest loss and climate change on range shifts. The effect was particularly acute in warm tropical regions emphasizing the importance of understanding how multiple stressors, climate change and forest loss especially, will impact diversity.

See paper in Nature Communications

How does tropical habitat variation affect seasonal polyphenism?

Bicyclus (anynana especially) butterflies are well known for their spectacular ability to change wing color and eyespot size plastically. These changes often occur seasonally, i.e. polyphenism. What's less clear is how such polyphenism might vary across habitats. While Michel collected Bicyclus dorothea in Cameroon from ecotone/savanna and forest habitats for use in his rearing experiments (more on this next year hopefully), he also measured a range of morphological traits over two years of collection. Populations from the ecotone were more variable in eyespot size. While the climatic influence on polyphenism is well-known, this study shows how habitat gradients can further alter morphology.

See paper in Environmental Entomology

Butterflies often become darker in low temperature environments. But what about moths?

Most of Shuang's PhD thesis set out to test the thermal melanism hypothesis on tropical butterflies. So do tropical butterflies tend to be darker in cooler environments? Shuang found that for tropical and subtropical ecosystems in China and Australia that the answer was yes. But what about moths? After many discussions with Roger, Louise and Aki, we decided that their moth community sampling from southwestern China could potentially address this question (and within the group our guesses as to what the answer might be was quite variable!). Shuang then set about photographing lots and lots of moths and analysing moth color across elevation. Indeed, she found a strong correlation between air temperature and the darkness of the moth assemblages, consistent with the thermal melanism hypothesis, and also consistent with UV as a potential factor in the morphology changes. Climate change effects will be filtered by the morphological traits of organisms and this study shows how nocturnal species might use such traits in unexpected ways to mediate warming impacts in the future.

See paper in Oecologia

Does habitat shape climate change vulnerability for tropical ectotherms?

Felix began his MPhil studying gecko oviposition. His attempt to lure geckos into laying eggs into strategically located PVC pipes in Hong Kong was a complete failure. He wisely changed his topic to skink thermal performance. After an early meeting with Adam and building on his previous work, Felix made his way to Cameroon and quickly made his reputation as "Atango". After extensive field and lab work in ecotone and forest sites across Cameroon in two separate field trips, he began applying mechanistic models to understand potential warming impacts on the skink, Trachylepis affinis. He also teamed up with Laurent and Matthew to map T. affinis distributions and model climate change effects on habitat suitability. Altogether he found very clear and divergent differences in how climate change might impact forest or ecotone populations of the same species of skink. The paper provides a case study for how habitat can shape physiology and potentially alter climate change vulnerability for tropical ectotherms.

See paper in Ecography

Concluding thoughts…

This is just a sample of some of the research to come out of the group this year. For a full list of papers see the lab's publications page. We've also done a great deal of other important work including conferences (ALCS5!), teaching, and public seminars of various sorts. Tim (and Marie) also spent two incredible months in Chile on a Universitas 21 fellowship. So thanks again for all your support. Stay in touch and keep your eyes open for more in 2019...