Humans fancy themselves complicated, but when it comes to genes, we’ve got nothing on a nearly microscopic water flea. In fact, the international Daphnia Genomics Consortium now reports that Daphnia pulex, a critical freshwater species, has the most genes of any animal yet sequenced. And it uses them to perform remarkable feats. Daphnia’s genome responds to environmental triggers, including predators, and spurs the growth of helmets and spikes for self-defense—in just one generation. 

(via kateoplis)