21.   They have argued that early modern humans all emerged from Africa and wiped out the Neanderthal population in Europe.

22.   They are already in early human testing.

23.   They suggest that the burning practices of early humans may have affected how far into the continent the monsoons penetrated.

24.   With some exceptions, experts say, large-scale extinction of big animals generally coincided with the arrival of early modern humans in places where they had never been.

25.   You may recall seeing prehistoric carvings on the walls of caves done by early humans who depicted various forms of food.

26.   Prompted by this success, Gilead is starting early human testing of an oral HIV drug that would work similarly, although results are several years away.

27.   Early humans may have been on islands.

28.   More recently, they have urged scientists to prove early humans developed in China, not in Africa as commonly held.

29.   Others say the Neanderthal was biologically absorbed by early modern humans and disappeared as a distinct and separate species.

30.   Some propose the extinctions were caused by climate changes while others blame the early humans.