Dr. Gordon is an evolutionary biologist and behavioral ecologist, interested in why and specific color patterns have evolved in different species and how that is related to the threat of predators.

Dr. Gordon is a first-generation Caribbean-Canadian and grew up in Montreal. She earned her undergraduate degree from Michigan State University, her Master’s degree at McGill University, and her Ph.D. from the University of California, Riverside. Prior to joining the faculty at Wash U in July, she was a postdoctoral fellow at the University of Jyväskylä, in Finland, which was partially funded by the Academy of Finland.

The existence of diversity in nature provides a puzzle for the theory of evolution by natural selection: “survival of the fittest” would seem to suggest that once a trait offers a selective advantage, only individuals with that trait would survive - resulting over time in a population that is not diverse at all. The trait that Dr. Gordon uses to study this is wing color of the wood tiger moth. In this species of moth, males either have white hindwings or yellow hindwings. The color is a warning to predators that the moths are toxic to eat, but previous research has shown that the two colors are not equally effective at this - predators avoid the yellow-wing males more than the white-wing males. So why are there still white-wing males?

In a recent paper, Dr. Gordon set up a mating experiment, where a female moth was in a cage with 4 male moths: two with yellow wings and two with white wings. For each wing color, one male came from an “unmixed” background (multiple generations of the same color) and one came from a “hybrid” background. For each female, Dr. Gordon tracked which male she chose to mate with, how many eggs she laid, and how many of the eggs hatched successfully.

The results were pretty surprising. When evolutionary biologists see two versions of a trait (e.g., yellow and white wings) sticking around in a population, it is often because the hybrid has a survival advantage. This has the side effect of keeping both traits around in the population, which keeps producing more hybrids.

However, in this case, Dr. Gordon found that the hybrid background was an advantage only for the white-wing males (they produced the most offspring), whereas hybrid yellow-wing males were pretty much sterile. This suggests that to keep both white and yellow wings viable in the population, there must be some kind of interaction between wing color and genetic lineage that is more complicated than either one can explain on its own.