comparative anatomy and human brain evolution Flashcards
hindbrain parts
cerebellum and medulla oblongata
midbrain
optic lobes
forebrain
olfactory lobes, cerebral hemispheres, thalamic area
three characteristics that distinguish primates from other animals
eyes at front of face
excellent color vision
depth perception and good fine motor coordination
usually one infant per pregnancy, long period of childcare
larger brains
distinguish apes from other primates
live in trees (arboreal)
shoulder joints limber so can swing in trees
more intelligent with larger brains
hominids from apes
walk upright
unrotated big toe, helps with walking and running upright
pelvis and neck different
table
several species alive at same time
how long ago homo genus organisms appeared, what different
2-2.5 million years ago
dental pattern similar to modern humans, stone tools
when modern humans appear
appear within past 200000 years in asia and north africa, past 100000 years in europe
when other hominids die off
30000 years ago in europe and 18000 years ago in asia
great rift valley lead to speciation
west had wet tropical jungles, east had drier land with more grass and fewer trees
how does reduction in trees lead to upright posture
more exposure to sun so change how travel
can’t live in trees so walk
can see prey and predators over grass
faster locomotion
upright posture advantages
efficient and rapid mode of locomotion regulates body temperature tree climbing seeing hands free tools caring for offspring energy, height
fruit cause brain or brain cause fruit
getting fruit more complex than getting vegetables bc fruit is on specific trees, during certain seasons, highly competitive
primates needed good sensory, motor, spatial, and memory skills to get fruit and ability to deal with competitors and good communication
how did cooling system improve brains
larger brains evolved because more blood vessels evolved to cool the larger brain. there are holes in the skull so the blood vessels can be close to skin and release heat, without this brain would overheat if got too big
neoteny
keeping juvenile characteristics as an adult
slowing rate of development leads to retention in adulthood of features that appeared in earlier phase
how does remaining in juvenile stage of life for so long help brain development
infant skulls have fontanels, larger brain development bc skull can fit through pelvic girdle
more time for brain cells to be produced and develop
brain size and intelligence relationship
none
culture
mental, how the physical social and intellectual environments around us shape our behaviors and mental processes
structures that increase
cerebellum and cerebral hemispheres/cerebrum
structures that decrease
olfactory lobes, pons, optic lobe
proportionally smaller bc other structures have gotten larger
how increase or decrease would change behavior
increase in cerebrum means more learning and memory, speech
decrease in optic lobes changed when animals sleep and wake bc less good night vision
increase in cerebellum means more complex movement
worse send of smell
function of cerebrum
fish: reception and conduction of smell impulses
amphibians: sense of smell
reptiles: sense of smell
birds: control of instinctive behavioral patterns
humans: motor area, motor speech area, some visceral activities, association areas
cerebellum differences
amphibians: least complex, muscle movements
fish: swimming
mammals: most complex, upright walking
reptiles: four legs on land
bird: flying
what effect does smooth v crinkled cerebral hemispheres have
convolutions = more surface area, more neurons/connections without folds, not learning but instinctual behaviors
more information
two areas larger on cat
cerebrum bc learned behaviors
cerebellum bc good balance
optic lobes bc good eyesight
