Groundbreaking AI-powered research into butterflies has explored the under-studied evolution of females, contributing to a debate among evolution’s founding fathers.
The University of Essex research, published in Communication Biology – explores a controversy between Victorian scientists Charles Darwin and Alfred Russel Wallace.
Darwin thought that men had more variety because women often chose their mates based on male appearance.
While Wallace thought that natural selection between the sexes was the biggest factor in the difference.
For over a century, scientists have mainly studied men because their differences are more obvious, while women, with subtler evolutionary changes, have been less studied.
Using high-tech machine learning, Dr. Jennifer Hoyal Cuthill more than 16,000 male and female birdwing butterflies, with collaborators from the Natural History Museum and AI research institute Cross Labs, Cross Compass.
This is the first time that visual differences between the sexes have been examined in the species, which live in Southeast Asia and Australasia.
Birdwing butterflies were chosen for this study because of their spectacular wing color patterns and the differences between males and females.
Dr. Hoyal Cuthill, from the School of Life Sciences, said: “This is an exciting time, with machine learning enabling new, large-scale tests of long-standing questions in evolutionary science.
“For the first time, we are able to measure the visible extent of evolution to test how much variation is present in different biological groups and between both men and women.
“Machine learning gives us new information about the evolutionary processes that generate and maintain biodiversity, including in historically neglected groups.”
The study looked at photographs of butterflies from the Natural History Museum’s collections, which show a range of characteristics, such as wing shapes, colors and patterns, from different species.
It found that while men often have more different shapes and patterns, both men and women contribute to the overall diversity.
The study found that evolutionary patterns predicted by both Darwin and Wallace were found in the butterflies.
This shows that both men and women contribute to the diversity between species.
The males showed more variation in appearance, which ties in with Darwin’s idea that females choose their mates based on these traits.
However, the deep learning also found subtle variation in women, which matched Wallace’s predictions about natural selection, allowing for diversity in female phenotypes.
Dr. Hoyal Cuthill said: “Birdwings are described as one of the most beautiful butterflies in the world. This study gives us new insights into the evolution of their remarkable but endangered diversity.
“In this case study of photos of birdwing butterflies, sex appears to have driven the greatest evolutionary change, including extreme male shapes, colors and patterns.
“Within the birdwing butterfly group, however, we found contrasting examples where female birdwing butterflies are more diverse in visible phenotype than males, and vice versa.
“The high apparent diversity among male butterflies supports the real importance of sexual selection, from female mate choice to male variation, as originally suggested by Darwin.
“Instances where female butterflies are visibly more diverse than the males of their species support an additional, important role for naturally selected female variation in interspecies diversity, as suggested by Wallace.
“Large-scale evolutionary studies using machine learning offer new opportunities to resolve debates that have been open since the founding of evolutionary science.”
