They developed a new approach to analyzing amino acids:
Sponges are structurally simple, lacking complex traits such as a nervous system, muscles, and a though-gut. Logically, you would expect these complex traits to have emerged only once during animal evolution — after our lineage diverged from that of sponges — and then be retained in newly evolved creatures thereafter.
However, a debate has been raging ever since phylogenomic studies found evidence that our most distant animal relatives were in fact comb jellies. Comb jellies are considerably more complex than sponges, using a nervous system and muscles to detect and capture prey, for example, and a through-gut to help them digest it.
As such, if they were our most distant animal relatives, it would seem likely that the complex traits they evolved were later lost in simple animals such as sponges, or that they evolved twice over the course of evolutionary history — once in comb jellies and again, independently, in humans, sharks, flies and other related animals that have them.
Anthony Redmond, Postdoctoral Research Fellow in Trinity’s School of Genetics and Microbiology, is first author of the research article just published in leading international journal, Nature Communications. He said:
“It may seem very unlikely that such complex traits could evolve twice, independently, but evolution doesn’t always follow a simple path. For example, birds and bats are distantly related but have independently evolved wings for flight.
“However, instead of comb jellies, our improved analyses point to sponges as our most distant animal relatives, restoring the traditional, simpler hypothesis of animal evolution. This means both that the animal ancestor was simple and that muscles, and the nervous and digestive systems, although further elaborated upon in many lineages, have a single origin.”
Trinity College Dublin, “Scientists pinpoint our most distant animal relatives” at ScienceDaily
Curiously, they add,
Other researchers had come to different conclusions about our most distant animal relative, and that was the case even when they used the same data — they had just used different methods.
Trinity College Dublin, “Scientists pinpoint our most distant animal relatives” at ScienceDaily
Well, we’ll see what the other researchers say about whose methods are right.
Re the researcher’s comment, “It may seem very unlikely that such complex traits could evolve twice, independently, but evolution doesn’t always follow a simple path,” he is virtually admitting that Darwinism stretches (snaps?) the bounds of probability but no one is allowed to discuss that honestly. That is most likely why there is a controversy in the first place.
The paper is open access.
See also: Evolution appears to converge on goals—but in Darwinian terms, is that possible?
Sponge as first animal
Comb jelly as first animal: