ThefingernailsThey are used for more than just showing off beautiful manicure designs. According to a study conducted at the University of Florida (USA), whenappeared more than 55 million years agoin very small primates these structures helped our ancestors toimprove touchon the fingers, as well asthe ability to scratch and grasp.
In a work published in the magazineAmerican Journal of Physical Anthropology, the authors affirm that the analysis of the oldest fossils with nails confirms the idea that the nails developed in small bodies and previous theories that they evolved in parallel with an increase in the size of the primate body are discarded.
The material analyzed to reach this conclusion consists of remains of25 new specimens of Teilhardina brandti found in the last seven years in the Bighorn Basinin Wyoming (USA), 55.8 million years old, including parts of their upper teeth and ankle bones that show that they lived in trees.The nails of this small primate, similar to the lemur, allowed it to grasp the branches and move with agility through the trees. And as Ken Rose, co-author of the work, points out, “they arethe smallest ever known, either from living animals or fossils. “
“If you look at all the primates that exist today, they all show similar characteristics, but unlike humans, many of them live in trees,” adds Jonathan Bloch, a paleontologist and co-author of the study. “By finding the parts of the skeleton of this primitive primate, we were able to verify thatnails were present in the common ancestor of the group that includes lemurs, monkeys and humans“Bloch adds.
The study allows a better understanding of the evolutionary relationship of one of the oldest known modern primates, as well as the timeframes and environmental conditions that allowed thenail development on all fingers of the upper and lower extremities, a characteristic unique to primates.
