01-13-2005, 07:28 AM
Interestingly DNA also shows when evolution happened
For evolution to happen, the child species has to bud off from a part of the parent species
Only a small fraction of the parent species is involved in this budding off process
When this budding happens, there is a genetic bottleneck
and by checking DNA it is possible to calculate when exactly this budding happened
and how big the initial budding child species was
It is estimated that there were 10k humans involved in the final evolution to homo sapiens circa 150k years ago
The journey out of Africa was done by just 250 humans
After the Mt. Tauba eruption, there was large scale human extinction and the surivors were in small pockets of about 250 people
In the case of cheetahs for example it is calculated that all cheetahs alive today are descended from a single breeding pair that escaped the desertification of the last ice age 15k years ago
For evolution to happen, the child species has to bud off from a part of the parent species
Only a small fraction of the parent species is involved in this budding off process
When this budding happens, there is a genetic bottleneck
and by checking DNA it is possible to calculate when exactly this budding happened
and how big the initial budding child species was
It is estimated that there were 10k humans involved in the final evolution to homo sapiens circa 150k years ago
The journey out of Africa was done by just 250 humans
After the Mt. Tauba eruption, there was large scale human extinction and the surivors were in small pockets of about 250 people
In the case of cheetahs for example it is calculated that all cheetahs alive today are descended from a single breeding pair that escaped the desertification of the last ice age 15k years ago