[js1138]

I still hear references to the great bottleneck 70,000 years ago.

[shubi]

Yep, supposedly in humans. That seems to be reflected in the DNA, especially the mitochondrial DNA. However if there were only 20,000 individuals the number of possible alleles at any locus could be quite high.

It still refutes creationism.

[JeffAtlanta]

I still hear references to the great bottleneck 70,000 years ago

Not sure how this plays into creationism, but 70,000 years old does correspond to the great Toba eruption. The human race apparently came pretty close to being wiped out.