Lecture 10: Human population genetics

Question 1

Origin of humans:

Answer 1

• Linnaeus (1707-78) coined the term Homo sapiens
• TH Huxley (1863) discussed the similarity between humans&great apes
• Hominids and other great apes diverged ~5-7 million yrs ago

Question 2

Humans and chimps differences

Answer 2

differ about 1% nucleotides
-non coding DNA 1.24%
-coding DNA 1%
therefore about 30 million differences in total. only 1.5% protein coding (DNA) 1.5 of 30 mill = ~450,000 differences. If 30,000 genes then ~ 9 differences/gene

Question 3

around 4.2 MYA

Answer 3

Australopithecines: hominids that arose

Question 4

Hominids =

Answer 4

apes

Question 5

around 3.9-4.2 MYA

Answer 5

Australopithecus anamensis

Question 6

Around 3.0-3.9 MYA

Answer 6

Australopithecus afarensis

Question 7

around 1-2 MYA

Answer 7

Paranthropus: robust, small-brained hominid

Question 8

East African. Possible ancestors of the genus homo

Answer 8

• Australopithecus anamensis

- Australopithecus afarensis

Question 9

Homo erectus

Answer 9

~2.5 MYA. African

• earliest hominid outside Africa ~1.6 -1.9MYA.
• In Java until 27 thousand years ago (KYA)

Question 10

Homo heidelbergensis

Answer 10

~1 MYA

Descended from H. erectus in Africa

Question 11

Homo neanderthalensis

Answer 11

~28-250 KYA. Descended from H. heidelbergensis.

Question 12

Homo sapiens

Answer 12

Anatomically modern humans. Ethiopia. 154-160 KYA

Question 13

5 skulls from Dmanisi, Georgia

Answer 13

Researchers believe they’re all from one species

Question 14

two models suggesting how modern humans arose:

Answer 14

• Multi-regional model

- Out-of-Africa model

Question 15

Multiregional model:

Answer 15

transition form H. erectus to H. sapiens took place in many places. Gene flow between populations.

Question 16

Out od Africa model:

Answer 16

Less than 200KYA H sapiens emerged in Africa then spread around the globe, replacing other hominids (e.g. H erectus)

Question 17

TMRCA stand for

Answer 17

Time to our most recent common ancestor