Flatworms (acoels) represents an intermediate phase in the history of evolution between … – FiskeribladetFiskaren

Evolutionary Biologists states in an article in the renowned journal Nature, that the flat worm (acoel) is the link between jellyfish and man.

 

Mikromakkene flatworms (acoel) that live in sand and mud into the sea, proves to be very important for understanding the development step between jellyfish and humans, according to the University of Bergen, in a press release.

 

– flatworms are a key to understanding when bilateral symmetry arose, that when animals were given a symmetrical right and left sides. These are qualities that we find in more complex creatures such as flies, cats and humans, says evolutionary biologist Andreas Hejnol, the Sars Centre, University of Bergen, in a press release.

 

Together with colleagues at the Sars Centre, they have recently established flatworm key position once and for all, after repeated studies with the latest DNA analysis. The discovery was recently published in the scientific journal Nature.

 

We crawled into the sea

 

flatworms have three body punches, and a symmetrical right and left side, as complex animals we find on the earth today. Yet the only one hole to eating and stools, as easier prehistoric animals like anemones and jellyfish.

 

This mix of older and younger trends suggest that flatworms are in an intermediate phase between jellyfish and more complex vertebrates like flies, cats and humans. It is a sign that it has the same ancestor as man, according Hejnol.

 

– These moves also means that we crawled around among sand grains in the sea 560 million years ago, says Hejnol, with a smile.

 

Toasted evolutionary tree

 

Once upon a time when our common ancestor evolved shared it gradually into two branches. One consisting of current flatworms and another with other animals, like humans.

 

This cairn prevailing theory from the 1990s until 2011, when an international team of researchers concluded that the flatworm and people do not have the same ancestor, using new RNA analysis and alternative ways to perform the tests.

 

As a result, lost the flat worm its position as nøkkeldyr in evolutionary history for a while. It was reduced to a less successful creature for development purposes, on the same branch as humans. The new ancestor may have been much younger and more complex creature than the original, the new conclusion.

 

Scientific doubt

 

The discovery led to much scientific doubt, among others from Hejnol. He believes that the alternative development long the order is a result of the researchers omitted important data in their analyzes. If the other researchers were right, had børstemakken have evolved from an ancestor with a central nervous system, digestive track, mouth and anus.

 

– If these scientists were right, we had lost a very informative animal group, which helps us to understand the development of organs, says Hejnol.

 

But that’s no longer the case, according to Andreas Hejnol. He believes that he has reversed flat worm to its original location on the evolutionary tree, once and for all.