Animal origins shift to comb jellies
Genetic data confirm the marine predators have more ancient origin than simpler sponges
![](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2013/12/am_ryan1HR.jpg?fit=860%2C460&ssl=1)
DEEP ROOTS The comb jelly Mnemiopsis leidyi rests at the base of the tree of animal life, according to analyses of its genome.
Courtesy of Stefan Siebert/Brown Univ.