ECSS 2018: Ecology and Evolution of Color: an exciting, emerging frontier in integrative biology

The 2018 Early Career Scientists Symposium explored the Ecology and Evolution of Color. The 14^th annual symposium highlighted the work of up-and-coming scientists whose research foci span a breadth of subfields and levels of organization and who study color from diverse perspectives across spatial and temporal scales. The Department of Ecology and Evolutionary Biology’s event was held at the University of Michigan in Ann Arbor.

”Early career scientists often get fewer invitations than established scientists, but are doing some of the most exciting cutting-edge work,” said U-M EEB Professor Elizabeth Tibbetts, who chaired the event committee. “I'm always impressed by the quality of the presentations at the ECSS.”

Coloration is fundamental to the ecology and evolution of organisms and has a valuable research legacy across plants and animals, according the event website. Recent innovations in both technology and investigative approaches have propelled coloration to an exciting emerging frontier in integrative biology. The causes and consequences of color diversity provided a compelling and interdisciplinary topic spanning diverse research interests across the department.

The synthetic keynote speakers explored the current state of coloration research and suggested exciting future research directions: Molly Cummings, professor, Department of Integrative Biology, The University of Texas at Austin presented “The past, present and future of sensory drive: predicting signal variation from the seen to the unseen” and Marcus R. Kronforst, associate professor, Department of Ecology and Evolution, University of Chicago, presented “Characterizing the link between mimicry and mate choice in Heliconius butterflies.”

Nearly 150 people attended the symposium throughout the day, with over half from institutions outside U-M, including regional universities such as Eastern Michigan University, Michigan State University, Earlham College (alumnus Dr. Heather Lerner brings a contingent of her students every year), University of Windsor and University of Cincinnati. The farthest attendee hailed from the National Research Institute of the Amazon.

Common themes

“Color is multifunctional,” noted Talia Moore, a U-M EEB postdoctoral fellow who was on the ECSS planning committee. “In addition to visual communication, our speakers showed that forms of color protected organisms from UV radiation and provided antioxidants that help turtles thaw after spending the winter frozen solid.”

A common theme that struck seminar speaker Natasha Bloch, NSF Postdoctoral Fellow in Biology, University College London, was “the complexity that surrounds the evolution of color,” which she said “is driven by many more factors than we acknowledged a decade ago. Getting to understand color evolution requires integrating research on perception, immunity as well as the selective pressures imposed by biotic and abiotic factors.”

“Combining such a variety of color research into one symposium was fun,” said Tibbetts. “People who study color signals in birds might not usually think about flower pollen coloration, but there are some interesting general principles across taxa.”

Interesting research

“It was great to hear about color in unexpected systems, such as pollen (rather than petals) of flowers and females (rather than males) selecting for high quality mates,” said Moore. “It was also interesting to hear about how research on color and polarization in fish can help the Navy camouflage their submarines, and that similar mechanisms were responsible for color changes in both butterflies and mice. The audience, especially the speakers, asked spectacular questions, showing that they really engaged with the presentations,” observed Moore.

Seminar speaker Matt Koski, postdoctoral research associate, University of Virginia, found all the talks fascinating. “I was especially interested in the Marketa Zimova’s talk on how earlier snow melt is leading to mismatches between snowshoe hair coloration and their background. The talk nicely outlined whether behavior, plasticity and adaptation may occur in response to climate change. Second, I was fascinated by Ricardo Mallarino on the development of striped patterns in rodents.” As one of the few development talks he thought it was an important perspective that other talks didn’t touch on. “Finally, Julienne Ng’s work on macroevolutionary patterns of color diversification in flowers touched on some broadly important topics in E&E including evolutionary constraints.” 

Bloch really enjoyed hearing about the advances presented on flower color evolution. “For a long time research on flower color evolution focused on the role of pollinators driving color patterns and variation. During the symposium we learned protecting the flower’s organs and gametes from UV radiation and temperature can be very important drivers of flower colors.”Fitzpatrick found every talk interesting. “One of the most arresting pieces of science was the work that Molly Cummings is doing to understand the ways in which fish can detect polarized light and then facultatively manipulate their skin to increase their own camouflage,” she said. “This is a beautiful example of the two-fold power of basic research: it transforms our understanding of what is possible (who knew that fish could do that?) and lays the foundation for potentially powerful applications (increased ability for submarine camouflage).”

Future directions

“I think that the field now has the tools to really explore aspects of color that humans are not capable of seeing, such as polarization and UV,” said Moore. “Understanding how organisms express and sense these color patterns may help solve open ecological and evolutionary mysteries.

“Furthermore, the presenters highlighted the importance of preserving historical museum data so that the amount of organismal change in response to climate change can be measured. Moving forward, it will be crucial to continue to collect museum specimens and to determine the mechanisms underlying these organismal responses, which often manifest in color,” added Moore.

“I think the field of color evolution is stepping beyond addressing the canonical hypotheses regarding the function of color, as well as considering the constraints to color evolution,” said Koski. “First, most adaptive hypotheses for the evolution of color diversity are linked to the functions of color in communication, but consideration of alternative functions of pigmentation is often fruitful for explaining patterns of color evolution. Second, constraints to color evolution, either developmental, genetic or ecological, are especially important for understanding whether and how coloration will respond to shifting climates and species distributions.”

“The exposure to different approaches to the same types of question was really valuable,” said seminar speaker Beth Reinke, postdoctoral researcher, Penn State. “It increasingly requires attacking questions with multiple approaches, which this symposium was really great at introducing attendees to."

“I think color evolution is going to become more integrative, bringing together incredibly diverse fields like neuroscience, perception, physics, chemistry, behavior, ecology and genetics,” said Bloch. 

Advantages of ECSS

“Because we selected speakers at this early stage in their professional academic careers, we heard about work that is mostly complete, and work that the speakers designed and performed themselves, resulting in very personal and exciting presentations,” said Moore. “Students pre-graduation are less likely to show complete work, and professors in later career stages often present work that their students have performed.”

“The symposium provided an opportunity for cross-talk between members of the field that work in very different systems and may otherwise have never connected,” noted Koski. “Anyone studying the ecology and evolution of color has to be a truly integrative biologist, or at least think like one and know someone with a skill set to round out their own. The symposium brought together developmental biologists, theoreticians, ecological geneticists, genomicists and ecologists. The connections made at the symposium will hopefully lead to collaboration or simply further conversation among scientists with very different perspectives but very similar interests.”

"It's not only great for people attending to get to hear cutting-edge science, but also great experience for those of us who are in the job market and value feedback from our peers on our talks,” said Reinke. “It is also helpful to get to know other people in the same field at the same stage of our careers.”

“Not only is it a wonderful platform to bring together people who work on a similar subject, but it provides young scientists with the opportunity to share our research,” said Bloch. “It can also be very motivating to be selected for this symposium! It's always good to hear others find our research interesting.” 

“The University of Michigan ECSS is a unique opportunity to integrate across early career stages,” said Fitzpatrick. “The department seems committed to selecting topics that are integrative (like ‘color’). This means that the invited speakers may well be meeting for the first time since they are likely to be taking different approaches to the topic. Getting to know the other speakers, the hosts, and some of the attendees, was a privilege.”