Flashcards in 22. Mammals II: Primates, Hominid Evolution, CNS Deck (49):
Primates have a .... ancestor
Grasping limbs with opposable thumb
Primates - eyes?
Forward-facing (depth perception)
Primates - social?
- Reduced brood size
- Extended parental care
2 major groups of primates?
What are prosimians?
Lemurs, loris, etc.
Arboreal and nocural
Which primate is the only one entirely carnivorous?
New world vs old world monkey?
New world: South American - prehensile tail (to grasp/hold objects) present in most new world monkey, not in old world monkeys - flat nose, arboreal
Old world: Africa, Asia
Examples of Old world monkeys?
Example of New world monkeys?
- Spider monkey
- Howler monkey
- Vervet (Barbados - vs. South Africa)
What is the key difference between monkey and apes?
Larger brain to body size ratio
What are African Apes?
Gorrillas, chimpanzees, hominids
Gibbons, Orangutangs and African apes - what in common?
All lack tail
Size of gibbons?
Smaller than other apes
What can't orangutangs do?
Cross from one tree to another by branches (too big). Must go down, walk between them, climb back up.
4 large categories of hominids?
What was found about the ardipithecus ramidus in 2009?
That they walked upright (no use of arms like chimps), yet retained primitive big toe that could grasp a tree like an ape
Brain size of australopithecus?
35% of modern human brain
Lucy, an australopithecus afarensis, provided evidence that...
- Bipedalism evolved before brains fully evolved
2 early homo species?
Homo habilis (handy, skillful)
Homo erectus (standing)
Ardipithecus ramidus - how many years ago?
Australopithecus - how many years ago?
Homo habilis - how many years ago?
2.5-1.5 mya (first tool use: 2 mya)
Homo erectus - how many years ago?
1.6 mya - 250,000 ya
Facies of homo habilis?
Shorter jaw, bigger brain
First hominid to leave Africa and spread to Eurasia?
First fire use by?
Homo erectus physiology?
- As large as modern humans
- Smaller brain, thicker skull
2 recent homo species?
- Homo neanderthalensis
- Homo sapiens
Homo neanderthalensis - how many years ago?
Homo sapiens - how many years ago?
Homo neanderthalensis physiology?
- Short, stalky, powerful build
- Larger brain than homo sapiens
Reason of disappearance of homo neanderthalensis?
Extermination by homo sapiens
Homo sapiens - physiology?
- Larger brains than earlier homo species (complex social life)
Have homo sapiens interbreed with neanderthals?
DNA other than Homo sapiens?
- 2% in non-African from Neanderthals
- 5% in Melanesians from Denisovans
What other species could have coexisted with homo sapiens? When and where? Why went extinct?
- Extinction: 17,000 YA, volcanic eruption
Central nervous system?
Dorsal, hollow tube of nervous tissue
- Large cephalic ganglion (brain)
- Long tube inferior to it (spinal cord)
Peripheral nervous system?
- Cranial nerves from brain
- Spinal nerves from spinal cord
Unconscious physiological information (blood pressure, body temperature)?
PNS x Hormones
Autonomic commands (heart rate, sweating, salivation)?
PNS x Neurohormones
Conscious sensory information?
Hormones x Neural afferents
Voluntary commands and behaviour?
Neurohormones x Neural efferent
Rest and digest
Fight or flight
Four distinct features of human brain?
- Brain stem
Cerebrum - in mammals?
Role of cerebrum?
Intellect, learning, memory, language, consciousness