Animal genomes follow irreversible 'evolutionary highways' across thousands of species‎

A human, an octopus, and a coral could hardly look more different—yet deep inside their cells, their chromosomes still carry recognizable pieces of a genome inherited from an animal ancestor that lived more than 600 million years ago. Since then, their chromosomes have fused, split and rearranged countless times. Today, thousands of animal genomes have been sequenced.