Integrating fossils and molecules


Fossils and genes are the two principal ways to study evolution, but they are rarely studied together. This project allowed us to make the first integration of fossil and molecular records of cupuladriid bryozoans.

For me one of the most intriguing things we found was that when a new species formed it lived within the same region but not in the same habitats as it’s ancestor. This habitat separation persisted for 2 million years during which time the two ‘sister-species’ kept very similar shape and form to each other. After 2 million years the two species started to live in the same habitats, but as soon as they their morphologies started to show significant differences, suggesting that at that time they made their living in different ways.

What isn’t clear is if the new species started to look different when they began to live in the same habitats, or if they were only able to live in the same habitats once they had become sufficiently different. I assume that it is the latter given that when different species live successfully together they almost always have to make a living in a different way otherwise they out-compete each other. Unfortunately it is unlikely that there will be a fossil record of high-enough resolution to reveal the answer to such conundrum.

View the pdf of the paper by clicking on the image…