Maybe it’s the other way around in many cases. The arrow worm has recently been placed on the “evolutionary tree” in a way that is creating a challenge. Japanese scientists have decided that the two hundred or so species of arrow worm belong to a group that consists of much simpler organisms than themselves:
“Arrow worms are predators, they have nervous systems, they have developed sensory organs; but the other organisms they’re grouped with are much simpler,” says molecular geneticist and first author Ferdinand Marlétaz.
“If you place arrow worms here, it means there was probably a lot of independent simplification, rather than the independent emergence of complexity.”Nick Carne, “Weird worms challenge complexity argument” at Cosmos
Of course, if all members of the group were complex from a very early time, that would mean … we don’t go there. Just think, there was a time when anyone could recite a Darwinian explanation for everything in their sleep. Sweet dreams.
See also: Worm gives up sexual reproduction, loses 7000 genes
Giant Shipworm Found Alive Is Example Of Devolution
GMO Bacteria: Devolution Is An Evolutionary Advantage?
Devolution: Getting back to the simple life