Ancient DNA from the Puntali elephant’s fossilized petrous bone indicated it descended from a mainland counterpart, Palaeoloxodon antiquus, around 400,000 years ago. Those beasts weighed an estimated 10 tons each and were about 12 feet tall.
Sicily has never been terribly distant from the rest of Italy, and there could have been a land bridge connecting the two in prehistory. Whether it was there or not, the ancient elephants could have swum to the island if they were anything like today’s elephants.
Descendants of the large elephants that colonized Sicily were almost 6.5 feet smaller, and almost 8 tons lighter. That change is comparable, the authors wrote, to a human becoming the size of a Rhesus monkey.
“The evolutionary rate they estimated the elephants to shrink (adapt) is remarkable,” wrote Mirte Bosse, a conservation genomics researcher at Wageningen University in the Netherlands, who was not involved in the research. “We know that evolution can be rapid, but this is a striking example.”
While much work remains to pin down how long it took for the elephants to shrink, obtaining the DNA at all is a substantial accomplishment. Dr. Baleka made numerous attempts before she successfully pulled DNA from the petrous bone within the elephant’s skull. The difficulty resulted in part because ancient DNA begins to degrade from the moment of death, and survives best in frozen climates, but not in the heat of the Mediterranean.
That this team was not only able to extract viable DNA, but enough to sequence the genome offers the exciting possibility that this method might be replicated to study more fossils from similar climates. Dr. Bosse noted it was “very promising because we are now capable of making this travel through time much further back than previously anticipated.”