Exam Flashcards
What are the five forces of evolution?
Natural selection Random genetic drift Mutation Population mating structure Culture
Natural selection details
- Since the environment can’t support unlimited population growth, not all individuals get to reproduce to their full potential
- some traits make it more likely that a species will survive
- but we interfere with that with things like IVF and modern medicine which means it’s not the same anymore hence the massive ⬆️ in population size
- environment adaptation = competition over food, water, mates and living space
Genetic drift details
Changes in allele frequencies by chance
Population mating structure details
- e.g. chimpanzees = patrilineal- when the females hit sexual maturity they leave the group and find another one this creates gene emmergration b/c they bring new genes to the new group
- mate preference = no consensus on how important it is e.g. giving food/grooming
Mutation details
Error in copying the DNA
Culture details
- The development of an ability from simple to complex
- e.g. nut cracking in chimpanzees - when the females move groups they adopt the new way the new group crack nuts
What modern world advances will effect future evolution
- Social and religious attitudes towards population growth, birth control, abortion
- social attitudes about who to marry/not marry
- military culture
- domestication
- travel and transport improvements
- internet (e.g. online dating)
- genetic engineering
We are currently in the Tertiary Period which is made up of 5 epochs, which are called?
Palaeocene epoch 65-54 ma Eocene 54-38 ma Oligocene 38-24 ma Miocene 24-5 ma Pliocene 5-1.8 ma (Anthropocene)
Details of the Quaternary period
Beginning of the ice age - 1.8 ma
Includes the Holocene 11,000 ya -present
What do these stand for? KNM WT ER OH D
KNM = Kenya National Museums WT = West (lake) Turkana ER = East Rudolf (former name for Lake Turkana) OH = Olduvai Gorge specimens D = Dmanisi specimens
Details of the Olduvai Gorge (OH)
- in Northern Tanzania
- a steep sided ravine in the Great Rift Valley
- one of the most important palaeoanthropological sites in the world - excavated by the Leakeys
- homo habilis (1.9 ma)
- Paranthropus boisei (1.8 ma)
- homo erectus (1.2 ma)
- homo sapiens (17,000 ya)
The Cradle of Human Kind details
- South Africa
- an area with many limestone caves
- Malapa cave - Australopithecus Sediba
- Paranthropus, homo habilis
- Rising Star cave - homo naledi
Dmanisi cave details
- location Georgia
- 5 homo erectus skulls (1.8 ma) found but large morphology of skulls varies - not classified as different species because they are the same age and found in the same place
- oldest one outside of Africa
4 characteristics of hominins
1) Increased brain size
2) Decrease tooth size
3) Bipedal
4) Increased tool use
3 Ardipithecus groupings
1) Sahelanthropus
2) Orrorin
3) Ardipithecus kaddaba and ramidus