Anatomically Modern Humans Flashcards
What are the three models for explaining the origins of anatomically modern humans?
1) Recent Out-Of-Africa (replacement) Model
2) Assimilation Model
3) Multiregional Evolution Model
When do we first see anatomically modern humans?
150,000 - 200,000 BP
Cranial features of anatomically modern humans
- higher, more rounded skull
- vertical forehead
- smaller browridges
- smaller, flatter face
- smaller teeth
- projecting chin
- more gracile post-cranial skeleton
Recent Out-of-Africa Model
- earliest anatomically modern human are found in Africa
- Archaic & AMHs overlapped briefly in areas into which AMHs later moved
- sudden change in technology & behaviour during replacement event
- genetic evidence of distinct differences between archaic & AMHs
Assimilation Model
- earliest Anatomically modern humans are found in Africa
- there was interbreeding between archaic & modern humans
- diffusion of technological & stylistic traits between archaic & modern populations
- no archaic genes in modern populations due to assimilation by a larger, more diverse population.
Multi-regional Evolution Model
- transitional fossils in Africa, Europe & Asia with both archaic & modern characteristics
- continuity in technology & behaviour
- genetic lineages emerging from different regions & gene flow between these regions
Where can fossil evidence of anatomically modern humans be found?
Africa, Asia, Europe, Australia
-both derived & ancestral features
What is the “molecular clock”?
- all living people are genetically related
- all variations evolved from a common ancestor
- measures mutations in gene sequences over time to estimate time of divergence
Multiregional Evolution?
The multi-regional hypothesis argues that our early hominid ancestors, including Homo ergaster and Homo heidelbergensis, migrated out of Africa and thus the evolution of modern humans took place in different parts of the world – a process termed regional continuity. This theory places great emphasis on the notion of steady evolutionary alterations or changes that happen in different regions and produce diverse variations of the species.
List four assumptions in using mtDNA(Mitochondrial DNA) to calculate the last common ancestor?
- random mating has occured
- rate of mutation has been contact
2 more
when did Anatomically modern humans settle in New Zealand?
no earlier than mid-13th century AD
When did anatomically modern humans settle in New Britain and Ireland?
settled in 35,000 BP
When did anatomically modern humans settle in the Solomon Islands?
in 28,000 BP
When did anatomically modern humans settle in the eastern Melanesian islands, Micronesia & Polynesia?
3,500 BP
How did anatomically modern humans settle new continents?
- knowledge of ocean currents
- knowledge of wind patterns
- navigated by the stars
- cloud patterns
- bird flight patterns
- seaworthy vessels
