DNA solves ancient animal riddle that Darwin couldn’t
(CNN) After the last of its kind died there about 12,000 years ago, a strange animal that disturbs Charles Darwin was finally added to the tree of life, according to a new study in the journal Nature Communications.
Macrauquenia lived during the last ice age. He looked like a big camel with no hump, with a long neck like a flame and a small trunk of a nose.
Long-necked herbivores would reach the leaves of plants and shrubs through what is now South America and open landscapes of Patagonia.
“It was a fairly large quadruped, probably not very light on feet,” said Ross MacPhee, co-author and curator at the American Museum of Natural History. “His outstanding feature, however, was his nose.
We do not have soft tissue fossils, so we do not know if the nose has developed into a real trunk, like an elephant, or rather like a large tapir-like fleshy appendage horn. It would not look like something alive today. ”
The nasal opening is only between the eye sockets, rather than just above the teeth.
The legendary British scientist Darwin found the first fossil of this creature and those other extinct animals belonging to the category “Native Ungulés of South America”, in 1834.
The fossils were given to Richard Owen, a British paleontologist, to study. Neither Owen nor Darwin could clarify the combination of features of a modern Macrauchenia or simply a line of distinct mammals. But they had bones and the bones of the vertebrae to study.
The group of ungulates itself raises concerns researchers because some of them appear to be elephants, while others are more similar to moles and moles. Owen even used an old name for the mud to provide the Macrauchenia type.
“What we have known for some time is that there are many species that are placed in this group, and many of them have a very particular look,” said Michi Hofreiter, lead author of the new study and an expert on paleo-genomics at the University Of Potsdam. “All of them are off, and they do not even know if they are from a single group or belong to different phylogenetic groups.”
An earlier study tried to place Macrauchenia in the tree of life using an old collagen. The new study, by MacPhee and Hofreiter, was built in the collagen study 2015 by extracting mitochondrial DNA from a fossil found in South America. The researchers also used a new approach to recover the Macrauchenia genome even without a modern analogue.
“I am pleased that our past results of protein for Macrauchenia are checked using this evolution in the ancient DNA alignments of a deeply diverged modern mammal without close relatives,” said Frido Welker, study author Collagen 2015. ” The absence of a close relative to obtain an almost complete mitochondrial genome is impressive. ”
Prior to these studies using proteins and DNA, the arguments for which the animal belonged derived bone morphology, main possibilities.
Macrauquenia now belongs to a brother group of perisodactyls, which includes horses, rhinos and tapirs. The two separate clusters exist about 66 million years ago when massive extinction occurred when an asteroid struck Earth.
“Now we have found a place in the tree of life for this group, now we can better explain how the characteristics of these animals evolved,” Hofreiter said. “And we have lost an older branch in the tree of life of mammals when the last member of this group died.”