ISCC Webinar - John Wiens presents How life became colorful: the evolution of conspicuous colors (and their functions) in plants and animals

How life became colorful: the evolution of conspicuous colors (and their
functions) in plants and animals

In this talk, I will discuss recent work by my collaborators and myself on the evolution of colors in animals and plants. Plants and animals are often adorned with potentially conspicuous colours (e.g. red, yellow, orange, blue, purple). These include the dazzling colours of fruits and flowers, the brilliant warning colours of frogs, snakes, and invertebrates, and the spectacular sexually selected colours of insects, fish, birds, and lizards. Such signals are often thought to evolve by utilizing pre-existing sensitivities in the receiver’s visual systems (e.g. sexually selected coloration evolved to utilize sensitivities to brightly colored fruit). This raises the question: what was the initial function of conspicuous colouration and colour vision? Here, we review the origins of colour vision, fruit, flowers, and aposematic and sexually selected colouration, and when each one evolved. We find that aposematic colouration is widely distributed across animals but relatively young, evolving only in the last ~150 million years (Myr). Sexually selected colouration in animals appears to be confined to arthropods and chordates, and is also relatively young (generally <100 Myr). Colourful flowers likely evolved ~200 million years ago (Mya), whereas colourful fruits/seeds likely evolved ~300 Mya. Colour vision (sensu lato) appears to be substantially older, and likely originated ~400–500 Mya in both arthropods and chordates. Thus, colour vision may have evolved long before extant lineages with fruit, flowers, aposematism, and sexual colour signals.  We also find that there appears to have been an explosion of colour within the last ~100 Myr, including >200 origins of aposematic colouration across nine animal phyla and >200 origins of sexually selected colouration among arthropods and chordates.

Bio:

John J. Wiens is a Professor in the Department of Ecology and Evolutionary Biology at the University of Arizona.  Prior to coming to Arizona in 2013, he was an Associate Professor and Assistant Professor at Stony Brook University in New York (2003–2012).  Before that he was a curator of herpetology at the Carnegie Museum of Natural History in Pittsburgh (1995–2002).  He obtained his Ph.D. at the University of Texas at Austin (1995), and his B.S. degree at the University of Kansas (1991).  He has served as an Associate Editor for several journals in ecology and evolution (e.g. American Naturalist, Ecography, Ecology Letters, Evolution, Systematic Biology) and as Editor-in-Chief of the Quarterly Review of Biology.  He is an ISI Highly Cited Researcher and a winner of the President’s Award of the American Society of Naturalists.  He has published >250 scientific papers.  He studies many questions in ecology and evolutionary biology, and especially the origins of biodiversity patterns and the impacts of climate change.  He is also interested in phylogeny, speciation, sexual selection, niche evolution, and the biology of reptiles and amphibians.  He has been interested in the evolution of conspicuous colors in animals for many years.