Genome Sequencing Reveals Surprising Insights Into Sea Turtle Evolution

Around 100 million years ago, a group of land-dwelling turtles took to the oceans, eventually evolving into the sea turtles that we know today. In research recently published in the Proceedings of the National Academy of Sciences, an international team of 48 researchers led by the University of Massachusetts Amherst revealed an incredibly detailed genetic map of two species–green and leatherback turtles–which is packed with surprises that might hold the key to their survival in a rapidly changing world. To precisely catalogue the turtles’ genomes, the international team turned to new technologies including long read sequencing. It turns out that green turtles have evolved more genes dedicated to immunity, suggesting an immune system that is better prepared for new pathogens, as well as more olfactory receptors–they have better senses of smell. The leatherback genome also shows that they lower genetic diversity and have historically had lower population levels. This work feeds into the growing scholarship on the importance of microchromosomes in vertebrate evolution and will help conservation biologists make more informed decisions about how best to protect these animals as they face the challenges of adapting to our rapidly changing planet.