The semiarid grassland region that is a transition zone between a desert to the north and a tropical savannah climate zone to the South is called the . A. Sahara
B. Atlas Mountains
C. Sahel
D. Nike River Valley

Which kind of organism is a heterotroph?

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

Imperial crisis inflation invasion pax romana great schismtrade during the , roman generals warred over succession. these conflicts drew soldiers away from the frontier and made the empire vulnerable to