Sentences with phrase «few tens of thousands of years»

Black is the original or «normal» skin color for humans — lighter skin colors evolved in the last few tens of thousands of years as populations adapted to higher latitudes.

«It is fascinating to see direct evidence that these archaic species did exist (alongside us) and it's only for the last few tens of thousands of years that is unique in our history that we are alone on this planet and we have no close relatives with us anymore,» he said.

Neanderthal bones found in a Spanish cave have been dated to 430,000 years ago, suggesting their ancestors left Africa nearly half a million years ago and ventured across Europe as far as southern Siberia before dying out only a few tens of thousands of years ago.

Carbon - 14 dating is only useful for a few tens of thousands of years.

It's the difference between a few tens of thousands of years, and being able to date back hundreds of millions of years.

It's a matter of faith among scientists that soft tissue can survive at most for a few tens of thousands of years, not the 65 million since T. rex walked what's now the Hell Creek Formation in Montana.

However, the sheer size of the system is not the only intriguing aspect of this particular flare; it is also the first one for which scientists can assume with some degree of certainty that the black hole was on a more standard «gas diet» very recently (a few tens of thousands of years).

Only a few tens of thousands of years ago, such charismatic megafauna ruled the earth.

Other human populations evolved from subsets of that diverse population, as small groups migrated around the globe just a few tens of thousands of years ago.

The water will migrate downward through slushy ice to the subsurface ocean within a few tens of thousands of years, researchers reported today at the European Planetary Science Congress in Madrid.

The stars may be passing through a stage of stellar evolution that lasts no more than a few tens of thousands of years, the scientists say — a phase between red giants (about 30 or 40 times the size of our sun) and blue subdwarfs (stars about one - fifth the size of our sun but seven times hotter and 70 times brighter).

A new study of wax from fossilized plants of the time suggests that 12 trillion tons of methane gas entered the atmosphere over just a few tens of thousands of years.

For a few tens of thousands of years — a fleeting moment in geological time — conditions were just right for near - perfect fossilisation.

Furthermore, very rapid (over a few tens of thousands of years) environmental changes in the geological past were often accompanied by mass - extinctions due to conditions changing faster than ecosystems could adapt to them.

In a few tens of thousands of years, our descendants will probably be struggling with volatile weather, dust storms and air that can not support many crops.

The global climate could change abruptly — that is, over the course of only a few tens of thousands of years.