But that trunk had to branch off at some point, or we wouldn’t have all of today’s animals. And that first split has been a bit elusive to scientists, due to it taking place around 600 million years ago. For decades, scientists have debated which group of animals traces its lineage back to the “sister” of literally all other animals. And now, thanks to new methods enabling researchers to analyze these creature’s chromosomes, scientists believe they finally have the answer. The sister to all other animals, the first to branch off, and the most genetically isolated animal is … drumroll please … the comb jelly!