CRITICAL THINKING problemS- 
PRIMATE CHARACTERISTICS
1. Many primates have opposability in their big toe in addition to their thumbs. How do 
you think daily life would be impacted if Homo sapiens had opposability in their big 
toes? How do you think daily life would be impacted if Homo sapiens were full-time 
quadrupeds instead of fill-time bipeds? describe your answer.
2. describe some reasons why humans have been able to expand in number and distribution 
to a greater extent than most other animals.
3. A key innovation is some modification in structure or function that permitted a species to 
exploit the environment in a more efficient or novel way, compared to ancestral species. 
Speculate on what might have been a key innovation in human evolution. Describe how 
that innovation might be the basis of an adaptive radiation in environments of the distant 
future.