Following the reptilian extinctions at the close of the Mesozoic era, two groups of mammals, the marsupials and ________, evolved and expanded
Fill in the blank(s) with correct word
placentals
You might also like to view...
An eagle standing on a rock lifts off in flight. As soon as it leaves the rock, support force by the rock
A. gradually diminishes. B. gradually increases. C. no longer acts. D. remains constant.
A sea or land breeze is caused by
a. ?differences in humidity. b. ?temperature differences. c. ?the Coriolis force. d. ?ocean tides. e. ?strong surf conditions.
The fact that a declining birth rate can still lead to population growth ________.
A. is due to a lowering of the infant mortality rate B. is referred to as population momentum C. can only happen if the life expectancy of the older population increases D. is incorrect since if the birth rate declines, so too does the population
Researchers at the Malpai Borderlands in southern New Mexico and Arizona have found evidence that ________
A) desertification has resulted in soil compaction and erosion B) fire suppression has played a major role in the degradation of the rangeland in the area C) the region cannot sustain any level of commercial ranching D) ranchers have been planting mesquite to replace lost grasslands E) ancient nomadic tribes permanently altered the landscape by settling down and ranching in one area