Ancient mammals could regrow limbs: study

Some amphibian groups around 300 million years ago may have regenerated legs and tails in a way similar to salamanders, according to a new study which suggests that all land mammals once had the ability to regenerate limbs.
A team of paleontologists from the Museum fur Naturkunde in Berlin, the State University of New York at Oswego and Brown University in a new study of fossil amphibians found that the extraordinary regenerative capacities of modern salamanders are likely an ancient feature of four-legged vertebrates that was subsequently lost in the course of evolution.
Researchers investigated different amphibian groups of the Carboniferous and Permian periods and showed that different groups of fossil tetrapods were able to regenerate their legs and tails in a way previously exclusively known from modern salamanders.

"We were able to show salamander-like regenerative capacities in both - fossil groups that develop their limbs like the majority of modern four-legged vertebrates as well in groups with the reversed pattern of limb development seen in modern salamanders," said Dr Jennifer Olori of State University of New York at Oswego, and co-author on the study.
The fossils used in the study derive from the collections of a number of Natural history museums among them the Museum fur Naturkunde Berlin.
"The fossil record shows that the form of limb development of modern salamanders and the high regenerative capacities are not something salamander-specific, but instead were much more wide spread and may even represent the primitive condition for all four-legged vertebrates," lead author Nadia Frobisch from the Museum fur Naturkunde was quoted as saying by 'Discovery News'.

"The high regenerative capacities were lost in the evolutionary history of the different tetrapod lineages, at least once, but likely multiple times independently, among them also the lineage leading to mammals," she said.