Earliest known complex life-forms identified as animals - Printable Version +- Scivillage.com Casual Discussion Science Forum (https://www.scivillage.com) +-- Forum: Science (https://www.scivillage.com/forum-61.html) +--- Forum: Biochemistry, Biology & Virology (https://www.scivillage.com/forum-76.html) +--- Thread: Earliest known complex life-forms identified as animals (/thread-5915.html)

Earliest known complex life-forms identified as animals - C C - Aug 8, 2018 https://www.sciencemag.org/news/2018/08/these-half-billion-year-old-creatures-were-animals-unlike-any-known-today EXCERPT: So-called Ediacaran organisms have puzzled biologists for decades. To the untrained eye they look like fossilized plants, in tube or frond shapes up to 2 meters long. These strange life forms dominated Earth’s seas half a billion years ago, and scientists have long struggled to figure out whether they’re algae, fungi, or even an entirely different kingdom of life that failed to survive. Now, two paleontologists think they have finally established the identity of the mysterious creatures: They were animals, some of which could move around, but they were unlike any living on Earth today. [...] To find out what sort of animals Stromatoveris and the other Ediacaran organisms were, Hoyal Cuthill and Han ran a computer analysis that uses anatomical features to reconstruct evolutionary relationships. They found that Stromatoveris and the other Ediacaran organisms don’t belong to any living animal group or “phylum.” Instead, they cluster on their own branch in the animal evolutionary tree, between the sponges and complex animals with a digestive cavity like worms, mollusks, and vertebrates, the team reports today in Palaeontology. “This branch, the Petalonamae, could well be its own phylum, and it apparently lacks any living descendants,” Hoyal Cuthill says. “It looks very likely [the Ediacaran organisms] are animals,” says Simon Conway Morris, a paleontologist [...] Geobiologist Simon Darroch [...] is also comfortable with the idea that the Ediacaran organisms were animals and that a few survived into the Cambrian. MORE: https://www.sciencemag.org/news/2018/08/these-half-billion-year-old-creatures-were-animals-unlike-any-known-today RE: Earliest known complex life-forms identified as animals - Magical Realist - Aug 9, 2018