1. what is one feature that distinguishes homo sapiens?
(a) complex spoken language
(b) ability to control complex tools
(c) bipedalism

2. why was it difficult for humans to cultivate land prior to the end of the last ice age?
(a) soil was too cold and hard to break up with the stones.
(b) the large population of other humans made settling in one place dangerous.
(c) all the water that was needed for irrigation was frozen.

In some zoos, rare crosses between a male lion and a female tiger have produced hybrid offspring called "ligers." male ligers are sterile but some female ligers are fertile. in the wild, lion and tiger ranges do not naturally overlap, making such a cross unlikely. furthermore, the solitary behavior of tigers and the social organizations of lions create behavioral differences. the production of sterile male ligers is an example of read the following scenario to answer the following question. in some zoos, rare crosses between a male lion and a female tiger have produced hybrid offspring called "ligers." male ligers are sterile but some female ligers are fertile. in the wild, lion and tiger ranges do not naturally overlap, making such a cross unlikely. furthermore, the solitary behavior of tigers and the social organizations of lions create behavioral differences. the production of sterile male ligers is an example of a postzygotic barrier the founder effect sympatric speciation a prezygotic barrier

The internet is controlled by: (select one): a. statutes and court cases in federal and state courts in the united states. b. the advanced research projects agency (arpa) and the u.s. department of defense. c. no single government or organization. d. google, yahoo, and the other search engines which have proprietary interest in the content thereon.

Why is the netherlands vulnerable to changes in climate? a. the netherlands is against nuclear power. b. forests in the netherlands have been destroyed by acid rain. c. the netherlands wrote the kyoto protocols. d. the netherlands is low-lying country, and rising sea levels may cause flooding.