12
C) Paleozoic era.
D) Cenozoic era.
46) The amniotic egg first appeared in which group of animals?
A) amphibians
B) reptiles
C) birds
D) mammals
47) The first vertebrates to develop jaws were the:
A) fish.
B) amphibians.
C) mammals.
D) reptiles.
48) Which of the following would support a hypothesis that insects preceded amphibians on land
and were flourishing when the first amphibians evolved?
A) Amphibians and insects both have lungs in their terrestrial stage.
B) Amphibians and insects have many adaptations in common.
C) Amphibians and insects share a recent common ancestor.
D) Many amphibians are insectivores in their terrestrial stage.
49) Mammals arose as a dominant life-form after which event?
A) the start of the Quaternary period
B) the Cretaceous extinction
C) the Devonian extinction
D) the Cambrian explosion
50) An important characteristic common to most primates is:
A) large, front-facing eyes.
B) short or absent tails.
C) grassland habitats.
D) the use of tools.