The human Y chromosome began to evolve from an autosome hundreds of millions of years ago, acquiring a sex-determining function and undergoing a series of inversions that suppressed crossing over with the X chromosome1,2. Little is known about the recent evolution of the Y chromosome because onl...
And continuing with giant terrestrial taxa… I was awed by this reconstruction of the huge early elephantiform-relative Deinotherium, with the short, swollen trunk and downturned tusks– so bizarre! Looking down onto the roof of the mouth of an NHM specimen of Deinotherium. Big, sharper-...
Circumstances will differ from case to case, but the main cause for this genetic divergence will usually be the two populations’ continuing to adapt to their different environments through Darwinian Natural Selection. But even if the selective pressures in the two environments are very similar, the...