modern humans Flashcards
(104 cards)
what other homo species led straight into the homo sapiens species
homo heidelbergensis
where did the “technological colonizers” originate from
africa
were african hominins more similar to neanderthals or modern humans
modern humans
in 300 kya, when the expansion from africa was occurring, where did the neanderthals primarily end up
europe and west asia
in 300 kya, when the expansion from africa was occurring, where did the denisovans primarily end up
asia
in 300 kya, when the expansion from africa was occurring, where did the other archaic homos primarily end up
east asia and oceania
in 300 kya, when the expansion from africa was occurring, what else was expanding and evolving
the modes of tools originating expansion from africa outward
what are some derived characteristics of modern homo sapiens
- high forehead
- 1350 cc (smaller than neanderthal but bigger than other early homos)
- small face and teeth
- no prognathism but protruding chin
- less robust
- long limbs
what is the first possible homo sapien found and date found
skeleton from jebel ihroud, morocco with mode 3 tools found
- 300 kya
- very debated
what is the first conclusive homo sapien found and date found
skeleton from omo kibish, ethiopia
- 200 kya
- definitive homo sapien
what specific types of genes come from a male
Y chromosome genes
what specific types of genes come from a female
mitochondrial DNA
do homo sapiens have low or high genetic diversity
LOW GENETIC DIVERSITY
- all genes could be traced back to adam and eve theoretically
what are two reasons why homo sapiens have low genetic diversity
- evolved relatively recently (200kya)
- descended from a bottleneck population
do chimpanzees have a higher or lower genetic diversity than homo sapiens do
chimps have a higher genetic diversity
what continent is there more genetic diversity of homo sapiens than anywhere else on earth
africa
- helps explain the expansion of homo sapiens from africa theory
what is the trend between distance to africa and genetic diversity rates
the farther a population is from africa, the lower amounts of genetic diversity it has
what is the serial founder effect
this is a type of genetic drift where there is a small subset of the population that leaves its own population but they travel really far away which limits the genetic diversity in the new population
what time is it expected that the migrations out of africa happened
60kya
when is the LCA of denisovans, neanderthals, and homo sapiens dated to
700 - 500 kya
T/F samples of ancient DNA can be taken from fossils even as old as 1.6mya (mammoths time period)
TRUE
DNA degrades quickly but fragments can still be found as ancient DNA
T/F modern homo sapiens have some neanderthals ancestry still
TRUE mostly in southwest asia!
would african modern homo sapiens have some neanderthal ancestry
NO because the neanderthals were not located in africa, so just the populations that left africa would have interbred with them. so many african groups today are not neanderthal connected.
what are the two helpful genes from denisovan and neanderthal interbreeding that natural selection didnt remove
the two genes that were beneficial were:
- skin pigmentation
- high altitude hemoglobin