32. Vertebrates

The adaptation that freed vertebrates from water for reproduction and allowed them to radiate into diverse terrestrial environments was the __________.

Which of the following characteristics is not shared by extant birds and extant reptiles?

The opossum is an example of a(n) __________ mammal.

All mammals __________.

Unlike eutherians, both monotremes and marsupialsa. lack nipples.b. have some embryonic development outside the uterus.c. lay eggs.d. are found in Australia and Africa.

What two major lineages make up the living Amniota?

Which statement is true about endothermy in mammals and birds?a. They both inherited this trait from a common ancestor.b. Birds are more closely related to mammals than to reptiles.c. Endothermy arose independently in these two lineages.d. Birds are reptiles and all reptiles are ectothermic.

Compare amniotic eggs to placentas.