˗ˏˋ exam two ´ˎ˗ Flashcards
1
Q
what is a generalized trait?
A
- a trait that is useful for a wide range of tasks
- opposable thumbs
2
Q
what is a dental formula?
A
- the number of each type of tooth in one quadrant of the mouth, written as number of incisors: canines: premolars: molars
- 2:1:3:3 (new world monkeys)
- 2:1:2:3 (old world monkeys, apes, humans)
3
Q
what are the diets of primates?
A
common types: frugivores, insectivores, folivores, and gummivores (gums and saps)
4
Q
what is fission-fusion?
A
- societies in which group composition is flexible, such as chimpanzee and spider monkey societies
- individuals may break up into smaller feeding groups (fission) and combine into larger groups (fusion)
5
Q
what is fossil formation?
A
- forms by sediment accumulation
- lithification (process by which the pressure of sediments squeeze extra water out of decaying remains and replace the voids that appear with minerals from the surrounding soil and groundwater)
- permineralization (when minerals from water impregnate or replace organic remains, leaving a fossilized copy of the organism)
6
Q
what is chronometric dating?
A
- dating methods that give estimated numbers of years for artifacts and sites
- based on the measurement of radioactive decay of particular elements
- tend to harm/damage the fossil
7
Q
what are adapoids?
A
- lived in north america and europe
- divided into six families
- important features include the hallmarks of euprimates: postorbital bar, flattened nails, grasping extremities, and a petrosal bulla
- later-appearing true primates
8
Q
what are the origins of primates?
A
- arboreal hypothesis
- visual predation hypothesis
- angiosperm-primate coevolution hypothesis
9
Q
what is the arboreal hypothesis?
A
- many of the features of primates evolved to improve locomotion in the trees
- typically credited as first to propose this theory was frederic wood jones, one of the leading anatomist-anthropologists of the early 1900s
- grasping hands and feet for gripping different sized tree branches; flexible joints for reorienting the extremities in various different ways
10
Q
what is the visual predation hypothesis?
A
- matt cartmill studied and tested the idea that the characteristic features of primates evolved in the context of arboreal locomotion by looking at squirrels
- instead cartmill suggested that the unique suite of features in primates is an adaptation to detecting insect prey and guiding the hands (or feet) to catch insects
11
Q
what is the angiosperm-primate coevolution hypothesis?
A
- counterargument to the visual predation hypothesis
- primate ecologist robert sussman argued, the earliest primates were probably seeking fruit rather than insects
- fruit (and flowers) of angiosperms (flowering plants) often develop in the terminal branches
- diffuse coevolution (ecological interaction between whole groups of species (e.g., primates) with whole groups of other species (e.g., fruiting trees))
- any mammal trying to access those fruits must possess anatomical traits that allow them to maintain their hold on thin branches and avoid falling while reaching for the fruits
12
Q
what role does the big toe play in bipedalism?
A
it is robust (for push off while walking).
13
Q
what is the difference between robust and gracile australopithecines?
A
- robust: rugged or exaggerated features, large posterior dentition and large chewing muscles
- gracile: smaller and less robust features
- varying degrees of arborealism and bipedality
14
Q
what is the pleistocene?
A
- 2.6 million years to 11,000 years ago)
- known as the “ice age”
- experienced cycles between interglacial (warm/wet) and glacial (cool/dry)
- geography and climate affect hominin migration
- paleoclimate of africa was grasslands that expanded and shrunk
- new hominin adaptations: new foods, cultural solutions (tools), and behavioral adaptation=
15
Q
what is the acheulean tool industry?
A
- 1.5 mya
- characterized by teardrop-shaped stone handaxes flaked on both sides
- more complex in form and more consistent in their manufacture (uniformitity)
- carefully shaped both sides of the tool (bifacial flaking)
- prominent at african sites
16
Q
what are mousterian tools?
A
- named after the le moustier site in southwest france
- tone tool industry of neanderthals and their contemporaries in africa and western asia
- levallois technique (preparation of a core and striking edges off in a regular fashion around the core, then a series of similarly sized pieces can be removed, which can then be turned into different tools)
- saved and reused their tools
17
Q
what are modern homo sapiens?
A
- traits appeared in a mosaic manner (gradually and out of sync with one another)
- we have a set of derived traits that are not seen in archaic humans or any other hominin. (e.g.: increasing brain size and bipedal ability)
- modern skeleton is considered gracile (thinner and smoother)
- have a more globular braincase
- chin
- forehead tied to frontal lobe expansion
- slender frame is more adapted for efficient long-distance running and cooling an active body in hotter climates
