The Environment of Evolutionary Adaptedness Flashcards
How long ago do the following split off the family tree?
1. Orangutanes
2. Gorillas
3. Humans
4. Chimpanzees and bonobos
- 9-13 million yrs ago
- 8.5-12 million yrs ago
- 5.5-7 million yrs ago
- 1-1.5 million yrs ago
Compare how many pairs pf chromosomes (and total) humans and chimps have
Humans: 23 pairs, 46 total
Chimps: 24 pairs, 48 total
How long ago did the evolution of bipedalism occur?
About 7 million years ago
How long ago was the development of stone tools?
Almost 3 million years ago
How long ago did Homo heidelbergenisis (archaic Homo sapiens) split into two branches?
About 500,000 years ago
What are the two branches that the Homo heidelbergensis split into?
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
When was the emergence of the first fully formed humans?
Around 170,000 years ago
When was the first representational art depicted?
50,000 years ago
How long ago was agriculture developed?
About 100,000 years ago in the Middle East
How long ago was the first spacecraft carrying humans into orbit built?
About 60 years ago
What does “Pleistocene megafauna” mean?
Big Animals
What are five hypotheses about the selective pressures that drove our ancestors to walk upright on two legs?
- For carrying (weapons and tools, vegetable foods, water, infants)
- To travel between food trees
- For feeding from bushes (in order to reach higher fruit and nuts)
- For feeding on grass seeds
- For provisioning one’s family, carrying prey animals and valuable forage back to the home camp
What are three more ideas about the origin of bipedalism?
- Thermoregulation - upright stance, sun beats down on smaller area of body
- Predator-avoidance - upright stance means can see further
- Wading in estuaries, swamps, rivers - maybe permitted exploitation of riverine resources, not otherwise available