Human evolution 1, Lecture 4 Flashcards
(31 cards)
Primate ancestors
‘superorder’ of Euarchonta,
established around 80 mya
50 mya which two groups did the superorder of Euarchonta (primate ancestors) split into?
prosimians and simians
Another word for Simians
anthropoids
Prosimians characteristics
4
- grasping fingers and toes
- binocular vision
- mostly nocuturnal
- mostly arboreal
Arboreal meaning
live in trees
Which group are the direct ancestors of monkeys and hominoids?
Simians
Where did Simians orginate?
Africa or Asia
When did the different adaptive radiations of Simians occur?
over 40 mya
Simians characteristics
4
- overlapping fields of vision
- opposable thumbs (not all genera)
- live in groups (social)
- mostly diurnal
Humans vs. chimps
similarity
96% similarity overall,
99% similarity in coding DNA
Key characteristics of apes
4
- larger brain relative to body size (compared to other primates)
- flexible behaviour
- tail-less
- some highly social (social interactions)
Human ancestory
5
Hominoid(the ‘apes’) –superfamily
- Hominid(the ‘great apes’) –family
- Hominine(gorilla, chimp and human) –subfamily
- Hominin(human and chimp) –tribe
- Hominina(human) -subtribe
Australopithecus
what are they? and 5 characteristics
close relation to Homo sapiens All australopithecus had: 1. round jaw 2. brain size 35% of modern humans 3. stocky build 4. large teeth and jaws 5. various ways of moving, but can walk upright
Ardipithecus ramidus
summary
a key step towards human evolution? dated to around 4.4 mya chimp sized brain broader diet than modern chimps at least partly bipedal recent discovery
Plural of australopithecus
australopithecines
Paranthropus,
similar to australopithecus, validity is considered features: 1. flatness of face 2. brow ridge bone size 3. steepness of skull moving foward
Lucy
type of australopithecus, found in Ethiopia 3.2 mya skeleton 40% complete human-like teeth ape-like head
Is australopithecus a direct ancestor on the genus homo?
maybe
Many species of homo overlapped in time so what did this mean?
extinction? interbreeding?
Homo habilis
appearance of homo genus, 2.5 mya found with many stone tools short stature disproportionately long arms shorter jaw larger brain than australopithecus, 50% of current size of human brain
What replaced homo habilis?
homo erectus
Homo erectus features
8
- 2 mya
- 5 feet tall ish
- long straight legs (excellent walkers)
- thick skill with steep forehead
- larger brain (similar to modern human)
- but still prominent brow ridge
- rounded jaw
- ability to talk?
Homo erectus
social developement
used crude tools
built fires
social groups
cave dwellers/wooden shelters
Where were homo erectus from?
orginated in africa,
first hominin ro leave African continent?
