Human Evolution

Question 1

Closest living relatives to humans

Answer 1

Chimpanzees and bonobos (pygmy chimpanzees)

Question 2

Evidence that chimps and bonobos are our closest living relatives

Answer 2

Anatomy
Gene sequence: alignment of sequences
Molecular clock (after two populations split, they accumulate mutations independently; counting differences enables estimation of time of split)
Dating fossils

Question 3

Traits under recent positive selection in humans

Answer 3

Skin color: dark skin protects against UV and light skin helps with seasonal vitamin D3 production
Lactase persistence: enables milk digestion past infancy, more common in Europeans
Malaria resistance in East Africa
Ability to utilize high fat diet in Greenland

Question 4

What traits make us human

Answer 4

Ultimately, we don't know
Larger brain
Reduced hair coverage
Elongated thumb and shortened fingers
Language
Advanced ability for creation
Relative limb length

Question 5

Techniques that can’t be used in finding human-defining genes

Answer 5

GWAS and linkage: human-specific variants wouldn’t segregate among us (all people have them)

Question 6

How much difference between human and chimpanzee genome

Answer 6

Humans and chimps differ at 1% of their non-repeat bases