The Environment of Evolutionary Adaptedness

Question 1

How long ago do the following split off the family tree?
1. Orangutanes
2. Gorillas
3. Humans
4. Chimpanzees and bonobos

Answer 1

1. 9-13 million yrs ago
2. 8.5-12 million yrs ago
3. 5.5-7 million yrs ago
4. 1-1.5 million yrs ago

Question 2

Compare how many pairs pf chromosomes (and total) humans and chimps have

Answer 2

Humans: 23 pairs, 46 total
Chimps: 24 pairs, 48 total

Question 3

How long ago did the evolution of bipedalism occur?

Answer 3

About 7 million years ago

Question 4

How long ago was the development of stone tools?

Answer 4

Almost 3 million years ago

Question 5

How long ago did Homo heidelbergenisis (archaic Homo sapiens) split into two branches?

Answer 5

About 500,000 years ago

Question 6

What are the two branches that the Homo heidelbergensis split into?

Answer 6

Northern branch - adapted to Mediterranean climate, became Neanderthals, settled in Europe and Western Asia
Southern branch - adapted to harsh environmental circumstances, gave rise to ancestors Homo sapiens, only hominy species remaining

Question 7

When was the emergence of the first fully formed humans?

Answer 7

Around 170,000 years ago

Question 8

When was the first representational art depicted?

Answer 8

50,000 years ago

Question 9

How long ago was agriculture developed?

Answer 9

About 100,000 years ago in the Middle East

Question 10

How long ago was the first spacecraft carrying humans into orbit built?

Answer 10

About 60 years ago

Question 11

What does “Pleistocene megafauna” mean?

Answer 11

Big Animals

Question 12

What are five hypotheses about the selective pressures that drove our ancestors to walk upright on two legs?

Answer 12

1. For carrying (weapons and tools, vegetable foods, water, infants)
2. To travel between food trees
3. For feeding from bushes (in order to reach higher fruit and nuts)
4. For feeding on grass seeds
5. For provisioning one’s family, carrying prey animals and valuable forage back to the home camp

Question 13

What are three more ideas about the origin of bipedalism?

Answer 13

1. Thermoregulation - upright stance, sun beats down on smaller area of body
2. Predator-avoidance - upright stance means can see further
3. Wading in estuaries, swamps, rivers - maybe permitted exploitation of riverine resources, not otherwise available