Homonids (5) Flashcards
When and How did dinosaurs become extinct?
65 mya They couldn’t control their body temperatures so when the climate cooled, they died
What is evolution?
Evolution is a gradual change in the features or characteristics of a species over time
How does evolution happen? (4)
- Organisms that are adapted to environment survive and breed
- Genes will be passed onto offspring
- They compete with other individuals for space and food
- Survival of the fittest: individuals that are best adapted to their environment survive
What happened after the next extinct (34 mya)?
Mammals started to evolve. Development of primates.
What are primates?
A primate is any member of the biological order Primates, the group that contains all the species commonly related to the lemurs, monkeys, and apes, with the latter category including humans.
What are the similarities between a human and a chimp? (3)
- Flat nails
- Stereoscopic and color vision
- Short snouts
Hominin vs Hominid
Hominid – the group consisting of all modern and extinct Great Apes (that is, modern humans, chimpanzees, gorillas, and orang-utans plus all their immediate ancestors).
Hominin – the group consisting of modern humans, extinct human species and all our immediate ancestors (including members of the genera Homo, Australopithecus, Paranthropus, and Ardipithecus).
__% of all fossils in Africa
relating to the origin of
humankind
They confirm that ___
originated in Africa
35
Human
______ Africanus in
S.Africa (Mrs. Ples and Taung
child)
4-___ million years ago.
Australopithecus
2.6
When did Homo sapiens occur?
800 000 years ago
When did homo sapiens sapiens occur?
About 200 000 years ago Homo sapiens sapiens appeared.
Who found the homo sapien fossil?
Found in Sterkfontein by Lee Burger.
Physical features of Homo Sapiens. (5)
- Longer legs of fossil
- Small teeth
- Skull similar shape to Homo than Australopithecus
- Shape of foot and wrist – more modern and indicates bipedal lifestyle
- Small brain
Why was bipedalism so important? (5)
- Could see over the savannah and be on the lookout for predators and food
- Make and use weapons, carry them long distances hunting
- Bring food home
- Carry and protect young children
- Carry things and migrate further
Compare the pelvic girdles of chimpanzees, Australopithecus, and humans.
Human:
- Pelvis more bowl-shaped
- Supports leg and trunk in an upright position
- greater stability for walking and running
Australopithecus:
- Pelvis bowl-shaped: allowed for walking
upright
Chimpanzees:
- Tall, narrow pelvis
Compare the feet of chimpanzees, Australopithecus, and humans.
Humans:
- Big toe in line with others: walked upright
- Human foot designed to support the whole weight of the body and for walking or running
Australopithecus:
- Big toe more in line with others: started
- to walk upright
Chimpanzees:
- Grabbing big toe: for climbing trees
Compare how chimpanzees, Australopithecus, and humans walked.
Humans:
- Bipedal: walked upright
Australopithecus:
- Bipedal: walked upright
Chimpanzees:
- Walked on all 4s: quadruped
Compare the facial structure of chimpanzees, Australopithecus, and humans.
Humans:
- Flat face
Australopithecus:
- Long snout: prognathous
Chimpanzees:
- Long snout
Compare the dental arc of chimpanzees, Australopithecus, and humans.
Humans:
- Dental arc curved
Australopithecus:
- Dental arc slightly curved
Chimpanzees:
- Angular dental arc
Compare the teeth of chimpanzees, Australopithecus, and humans
Humans:
- Canines don’t protrude past other
teeth
Australopithecus:
- Canines less prominent
Chimpanzees:
- Prominent canines
Compare the teeth of chimpanzees, Australopithecus, and humans. (A diastema is a space or gap between two teeth)
Humans:
- No diastema
Australopithecus:
- No diastema
Chimpanzees:
- Diastema
Compare the cranium of chimpanzees, Australopithecus, and humans.
Humans:
- Large cranium
- Larger brain capacity
- Foramen magnum more centrally positioned under the skull, spine connects with skull underneath, so head is held firmly upright
Australopithecus:
- Bigger cranium
Chimpanzees:
- Smaller cranium
- Smaller brain capacity
- Foramen magnum at rear of skull
Compare the foramen magnum of chimpanzees, Australopithecus, and humans. (the hole in the base of the skull through which the spinal cord passes)
Humans:
- Foramen magnum more to the
front
Australopithecus:
- Foramen magnum to the front
Chimpanzees:
- Foramen magnum at the back of
skull
What did a larger brain mean? (2)
- More intelligence so language development
- Formation of culture and tribalism
What was Australopithecus?
Australopithecus, which means “southern ape”, was actually an upright-walking hominid with human-like teeth and hands. Its main ape-like features were a small brain, flattened nose region and forward-projecting jaws
