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1) stasis
• A) is an essential part of the gradualist model
of evolution
• B) refers to morphological stasis, not
molecular stasis
• C) suggests strong directional selection
• D) is more likely in dueterostomes
• E) none of the above
2) You are:
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A) a deuterostome
B) a protostome
C) an acoelomate
D) radially symmetrical
E) none of the above
3) The “age of mammals”
• A) is the mesozoic
• B) started with an adaptive radiation following
the demise of the dinosaurs
• C) is the cenozoic
• D) is about 300 million years old
• E) B and C
4) The phanerozoic
• A) is the period of time before the Cambrian
explosion
• B) consists of the Paleozoic, the Mesozoic, and
the Cenozoic
• C) was when atmospheric oxygen levels first
started to rise
• D) resulted from the end-Permian extinction
• E) killed the dinosaurs
5) Animal phyla
• A) are distinguished by differences in
embryonic development and adult body plan
• B) were mostly all present by about 535
million years ago
• C) probably diverged during or prior to the
cambrian explosion
• D) all of the above