According to fresh research, early humans could
never have come into contact with the giant carnivorous 'terror
bird' Titanis walleri.
It had been thought that the fearsome beasts
became extinct as little as 10,000 years ago - a time at which
humans shared their North American habitat. But in 2006 a US team
revised that date to about two million years earlier. The study
was published in Geology, managing also to shed light on the
flightless birds' migration to North America.
T walleri is thought to be the largest
species of the terror bird family. It would have stood two metres
tall (seven feet) and would have weighed 150kg (330lb). This
flightless species, which inhabited South America primarily with
an extension into North America, had an enormous beak and lived up
to its terror tag by being a top predator of its time.
The researchers looked at fossils of the birds
that had been uncovered in Florida and Texas. By analysing the
distribution of a group of chemicals known as rare earth elements
within the bones, the team was able determine the age of the North
Previously, scientists had believed that
Titanis became extinct about 10,000 years ago, according to
Professor Bruce MacFadden, a palaeontologist at the Florida Museum
of Natural History and lead author of the Geology paper.
This would have coincided with the mass extinction
of other megafauna which occurred in North America at the end of the
Pleistocene; a period of biodiversity loss which has sometimes been
blamed in part on humans and their novel spear technologies at the
time but which was largely caused by the end of the most recent ice
age and the rapidly changing climate.