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216 Cards in this Set
- Front
- Back
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metatheria
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Mammals that reproduce without a placenta, including the marsupials.
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prototheria
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Mammals that reproduce by egg-laying, then nurse young from nipples. The Australian platypus and echidna are the only living monotremes.
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eutheria
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Mammals that reproduce with a placenta and uterus.
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strepsirhine
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Infraorder of the order Primates that includes the prosimians, excluding the tarsier. Many are nocturnal. Reliance on olfaction, lack of complex social behavior, tooth comb.
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haplorhine
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Infraorder of the order Primates that includes the anthropoids and the tarsier. All are diurnal, except one (Aotus). Ectotympanic tube. Fused mandible. Back of orbit is closed.
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prosimian
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Member of the primate suborder Prosimii that includes the lemurs, lorises, galagos, and tarsiers.
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anthropoid
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Members of the primate suborder Anthropoidea that includes the monkeys, apes, and hominids.
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arboreal hypothesiss
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Hypothesis for the origin of primate adaptation that focuses on the value of grasping hands and stereoscopic vision for life in the trees.
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visual predation hypothesis
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Hypothesis for the origin of primate adaptation that focuses on the value of grasping hands and stereoscopic vision for catching small prey.
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dental arcade
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The parabolic arc that forms the upper or lower row of teeth.
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nocturnal
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Active at night.
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diurnal
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Active in the day.
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neocortex
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The part of the brain that controls higher cognitive function; part of the cerebrum.
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ontogeny
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The life cycle of an organism from conception to death.
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sociality
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Group living, a fundamental trait of haplorhine primates.
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Playtrrhini
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Infraorder of the order Primates that is synonymous with New World monkeys, or ceboids. 2-1-3-3 dental formula. Primarily arboreal, some have prehensile tails. Smaller body size.
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prehensile tail
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Grasping tail possessed by some species of the primate families Cebidae and Atelidae.
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polyandry
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Mating system in which one female mates with multiple males.
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Catarrhini
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Infraorder of the order Primates that includes the Old World monkeys, apes, and hominids.
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estrus
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Hormonally influenced period of sexual receptivity in some female mammals, which corresponds to the timing of ovulation.
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hylobatid (Hylobatidae)
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Member of the gibbon, or lesser ape, family.
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pongid (Pongidae)
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Orangutans. Asian great apes. Bornean and Sumatran.
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Gorillas (gorillinae)
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3 subspecies, mountain (very endangered), west lowland, east lowland.
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brachiation
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Mode of arm-hanging and arm-swinging that uses a rotating shoulder to suspend the body of an ape or hominid beneath a branch or to travel between branches.
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frugivorous
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An animal that eats a diet composed mainly of fruit.
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fission-fusion
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Form of mating system seen in chimpanzees, bonobos, and a few other primates in which there are temporary subgroups but no stable, cohesive groups.
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ecology
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The study of the interrelationships of plants, animals, and the physical environment in which they live.
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folivores
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Animals who eat a diet composed mainly of leaves, or foliage
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secondary compounds
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Toxic chemical compounds found in the leaves of many plants which the plants use as a defense against leaf-eating animals.
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phenology
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The leafing and fruiting cycles of a forest.
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activity budget
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The pattern of waking, eating, moving, socializing, and sleeping that all nonhuman primates engage in each day.
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home range
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The spatial area used by a primate group.
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core area
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The part of a home range that is most intensively used.
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territory
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The part of a home range that is defended against other members of the same species.
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captive study
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Primate behavior study conducted in a zoo, laboratory, or other enclosed setting.
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semi-free-ranging
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Primate behavior study conducted in a large area that is enclosed or isolated in some way so the population is captive.
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field study
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Primate behavior study conducted in the habitat in which the primate naturally occurs.
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polygynous
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Mating system consisting of at least one male and more than one female.
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matrilineal
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Pattern of female kinship in a primate social group.
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social system
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The grouping pattern in which a primate species lives, including its size and composition evolved in response to natural and sexual selection pressures.
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monogomy
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A mating bond; primates can be socially monogamous but still mate occasionally outside the pair bond.
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polygynandrous
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Primate social system consisting of multiple males and multiple females.
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dominance hierarchy
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Ranking of individual primates in a group that reflects their ability to displace, intimidate, or defeat group mates in contests.
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infanticide
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The killing of infants, either by members of the infant’s group or by a member of a rival group.
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polyandry
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One female with multiple male mates.
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fission-fusion polygyny
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Type of primate polygyny in which animals travel in foraging parties of varying sizes instead of a cohesive group
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female philopatry
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Primate social system in which females remain and breed in the group of their birth, whereas males emigrate.
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male philopatry
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Primate social system in which males retain and breed in the group of their birth, whereas females emigrate.
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sexual receptivity
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Willingness and ability of a female to mate, also defined as fertility.
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fossils
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The preserved remnants of once-living things, often buried in the ground.
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paleontology
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The study of extinct organisms, based on their fossilized remains.
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geology
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The study of the Earth.
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taphonomy
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The study of what happens to the remains of an animal from the time of death to the time of discovery.
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strata
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Layers of rock.
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stratigraphy
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The study of the order of rock layers and the sequence of events they reflect.
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geological time scale (GTS)
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The categories of time into which Earth’s history is usually divided by geologists and paleontologists: eras, periods, epochs.
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provenience
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The origin or original source (as of a fossil).
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relative dating techniques
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Dating techniques that establish the age of a fossil only in comparison to other materials found above and below it.
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lithostratigraphy
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Using rock layers to correlate ages across regions.
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tephrostratigraphy
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A form of lithostratigraphy in which the chemical fingerprint of a volcanic ash is used to correlate across regions.
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biostratigraphy
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Relative dating technique using comparison of fossils from different stratigraphic sequences to estimate which layers are older and which are younger.
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calibrated relative dating techniques
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Techniques that can be correlated to an absolute chronology.
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geomagnetic polarity time scale (GPTS)
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Time scale composed of the sequence of paleomagnetic orientations of sediments through time.
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Paleomagnetism
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The magnetic polarity recorded in ancient sediments. Reversed or normal direction is used to correlate with the geomagnetic polarity time scale to infer an age for a site.
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chronometric (absolute) dating techniques
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Techniques that estimate the age of an object in absolute terms through the use of a natural clock such as radioactive decay or tree ring growth.
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radiometric dating
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Chronometric techniques that use radioactive decay of isotopes to estimate age.
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isotope
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Variant forms of an element that differ based on their atomic weights and numbers of neutrons in the nucleus. Both stable and unstable (radioactive) isotopes exist in nature.
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half-life
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The time it takes for half of the original amount of an instable isotope of an element to decay into more stable forms.
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parent isotope
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The original radioactive isotope in a sample.
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daughter isotope (product)
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The isotope that is produced as the result of radioactive decay of the parent isotope.
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potassium-argon (K-Ar) dating
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Radiometric technique using the decay of 40K to 40Ar in potassisum-bearing rocks; estimates the age of sediments in which fossils are found.
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argon-argon (40Ar-39Ar) dating
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Radiometric technique modified from K-Ar that measures 40K by proxy using 39Ar. Allows measurement of smaller samples with less error.
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fission track dating
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Radiometric technique for dating noncrystalline materials using the decay of 238U and counting the tracks that are produced by this fission. Estimates the age of sediments in which fossils are found.
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uranium series (U-series) techniques
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Radiometric techniques using the decay of uranium to estimate an age for calcium carbonates including flowstones, shells, and teeth.
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radiocarbon dating
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Radiometric technique that uses the decay of 14C in organic remains such as wood and bone to estimate the time since the death of the organism.
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electron traptechniques
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Radiometric techniques that measure the accumulation of electrons in traps in the crystal lattice of a specimen.
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dose rate
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The amount of radiation to which an object is exposed over a period of time.
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thermoluminescence (TL)
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Electron trap technique that uses heat to measure the amount of radioactivity accumulated by a specimen such as a stone tool since its last heating.
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optical stimulated luminescence (OSL)
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Electron trap technique that uses light to measure the amount of radioactivity accumulated by crystals in sediments (such as grain sands) since burial.
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electron spin resonance (ESR)
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Electron trap technique that measures the total amount of radioactivity accumulated by a specimen such as tooth or bone since burial.
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paleosol
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Ancient soil! Whoopee!
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phytoliths
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Silica bodies produced by some plants, especially grasses, that can be used to indicate the presence of certain types of vegetation at a fossil site.
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plesiadapiforms (characteristics of)
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Mammilian order or suborder of mammals that may be ancestral to later Primates.
1) small brains, large snout, small eyes, no postorbital bar or bony ring, no opposible digits 2) molecular evidence suggests primate lineage, 63 mya |
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prognathic face
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Projection of the face well in front of the braincase.
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postorbital bar
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A bony ring encircling the lateral side of the eye but not forming a complete cup around the eye globe.
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diastema
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Gap between anterior teeth.
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adapoids
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Family of mostly Eocene primates, probably ancestral to all strepsirhines.
AQ, diurnal, medium to small size, probably ate both fruit and leaves. |
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omomyoids
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Family of mostly Eocene primates probably ancestral to all haplorhines.
Large brain, large orbits (nocturnal), not very prognathic, eating both insects and fruits. VCL, maybe AQ. |
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dental apes
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Early apes exhibiting Y-5 molar patterns but monkey-like postcranial skeletons.
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r-selected
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Reproductive strategy in which females have many offspring, interbirth intervals are short, and maternal investment per offspring is low.
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k-selected
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Reproductive strategy in which fewer offspring are produced per female, interbirth intervals are long, and maternal investment is high.
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molecular clock
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A systematic accumulation of genetic change that can be used to estimate the time of divergence between two groups if relative rates are constant and a calibration point from the fossil record is available.
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relative rate test
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A means of determining whether molecular evolution has been occurring at a constant rate in two lineages by comparing whether those lineages are equidistant from an outgroup.
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vertebral column
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The column of bones, and cartilaginous disks, that houses the spinal chord and provides structural support and flexibility to the body.
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cervical
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The seven neck vertebrae.
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thoracic
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The twelve vertebrae of the thorax that hold the ribs.
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lumbar
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The five vertebrae of the lower back.
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sacrum
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The fused vertebrae that form the back of the pelvis.
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coccyx
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The fused tail vertebrae that are very small in humans and apes.
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foramen magnum
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Hole in the occipital bone through which the spinal chord connects to the brain.
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nuchal plane
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Flattened bony area of the occipital posterior to the foramen magnum, to which neck muscles attach.
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innominate bones (os coxae)
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Thep air of bones that composes the lateral parts of the pelvis; each innominate is made of up three bones that fuse during adolescence.
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ischium
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Portion of the innominate bone that forms the bony underpinning of the rump.
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ilium
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The blade of the innominate to which gluteal muscles attach.
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pubis
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Portion of the innominate that forms the anterior part of the birth canal.
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gluteal muscles
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Gluteus maximus, medius, and minimum, the muscles of walking, which have undergone radical realignment in habitual bipeds.
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acetabulum
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The cup-shaped joint formed by the ilium, ischium, and pubis at which the head of the femur attaches to the pelvis.
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femoral condyles
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The enlarged inferior end of the femur that forms the top of the knee joint. Enlarged in bipeds to help support excess body weight.
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tarsals
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Foot bones that form the ankle and arches of the foot.
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metatarsals
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Five foot bones that join the tarsals to the toes and form a portion of the longitudinal arch of the foot.
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phalanges
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Bones that form the fingers and toes.
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technical intelligence
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Hominid intelligence and brain size increase modeled as a result of tool use and extractive foraging.
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ecological intelligence
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Hominid intelligence and brain size increase theorized as a result of benefits of navigating and foraging in a complex tropical forest ecosystem.
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social intelligence
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Hominid intelligence and brain size increase theorized as a result of benefits of being politically or socially clever while living with others; sometimes called Machiavellian intelligence.
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theory of mind
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Ability to place oneself into the mind of others; necessary for possessing an awareness of the knowledge or cognitive ability for others and for imitating or teaching others.
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homodont
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Having teeth that are uniform in form, shape, and function (not us).
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heterodont
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Tooth array in which different teeth have different forms and functions.
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CP3 complex
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Combination of canine and first premolar teeth that form a self-sharpening apparatus.
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australopithecines
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The common name for members of the genus Australopithecus.
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cranial crests
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Bony ridges on the skull to which muscles attach.
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megadontia
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Enlarged teeth.
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type specimen
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According to the laws of zoological nomenclature, the anatomical reference specimen for the species definition.
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sagittal crest
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Bony crest running lengthwise down the center of the cranium on the parietal bones; for the attachment of the temporalis muscles.
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compound temporonuchal cresst
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Bony crest at the back of the skull formed when an enlarged temporalis muscle approaches the enlarged neck (nuchal) muscles, present in apes and A. afarensis.
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breccia
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Cement-like matrix of fossilized rock and bone. Many important South African early humans have been found in breccias.
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endocast
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A replica (or cast) of the internal surface of the braincase that reflects the impressions made by the brain on the skull wall. Natural endocasts are formed by filling of the braincase by sediments.
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hard object feeding
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Chewing touch, hard-to-break food items such as nuts or fibrous vegetation.
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muscles of mastication
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The chewing muscles: masseter, temporalis, medial, and lateral pterygoids.
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postorbital constriction
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The pinching-in of the cranium just behind the orbits where the temporalis muscle sits. Little constriction indicates a large brain and small muscle; greater constriction indicates a large muscle, as in the robust australopithecines.
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zygomatic arch
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The bony arch formed by the zygomatic (cheek) bone and the temporal bone of the skull.
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osteodontokeratic culture
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A bone, tooth, and horn toolkit envisioned by Raymond Dart to be made by Australopithecus. Hasn't really held up to modern scrutiny.
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Cercopithecoidea
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"old world monkeys" (colobinae, ceropithecinae) Ischal collositices (tightening of bum skin), bilophodant molars (not Y5)
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hominid (hominidae) (family)
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includes gorillas, chimps, and humans
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hominin (hominini)
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humans and their fossil ancestors
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homininae (subfamily)
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humans, fossil humans, and chimps
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anatomical similarities of primates (skull)
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1) forward-facing eyes with stereoscopic vision (depth)
2) enclosed bony orbit 3) relatively large brain size |
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anatomical similarities of primates (other)
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1) flattened nails (instead of claws)
2) grasping hands with opposable thumbs and/or big toe 3) petrosal bulla (various levels of inflation) 4) tympanic bone (ring versus loop) |
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life history similarities of primates
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1) single offspring (or twins, like tamarins)
2) extended development before sexual maturity |
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behavioral similarities of primates
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1) both diurnal and nocturnal
2) very social! 3) types of locomotion |
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types of locomotion
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arboreal quadrupedal, terrestrial quadrupedal, knucklewalking, brachiators, vertical clinging and leaping, bipedalism, partial brachiation
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dietary similarities of primates
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Usually either leaf-eating, insect-eating, or fruit-eating.
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dental formula of primates
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2-1-2-3 in haplorhines (minus NWM)
2-1-3-3 in NWM varying in strepsirhines |
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Is that a strepsirhine?
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1) unfused mandible
2) ectotympanic ring 3) tooth comb incisors 4) eye socket not enclosed in bone (postorbital bar) 5) longer snout |
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Lemurs
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1) only found in Madagascar
2) both dirunal and nocturnal 3) female dominance |
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Aye-aye
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1) dental formula 1-0-1-3
2) continuously-growing incisors 3) elongated third digit (for foraging insects or scraping at bark) |
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Loris
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1) found across Africa and Asia
2) nocturnal (LARGE eyes) 3) solitary |
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Tarsiers
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1) eyeballs larger than brain
2) partially enclosed back of orbit 3) unfused mandible 4) ear tube 5) VCL 6) claws on digits 2 and 3 7) highly carnivorous Haplorhine and prosimian! |
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Colobinae
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High molar cusps (leaf-eaters), complex stomachs, long tails, deep jaw
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Cercopithecines
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Lower molar cusps, cheek pouches, short tail, wider incisors
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Advantages to being social
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1) security (protection from predators)
2) access to mates 3) finding food |
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Disadvantages to being social
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1) Competition for food or mates
2) More easily seen by predators 3) Limits individual something for the good of the group |
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Female outlook on reproduction
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Can only mate once in a while, more choosy, want to find the right guy. Low reproductive potential. Use man to find resources for them and kids.
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Male outlook on reproduction
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High reproductive potential, is less choosy. Concerned with female availability. Worried about quantity.
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Noyau
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solidaryity. Males won't really come into contact with group until mating time. Females live with kids. Strepsirhines, orangutans.
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Good places to die if you want to be a fossil
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1) by water (buried quickly)
2) exploding volcanos, volcanic ash |
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petrification (fossilization)
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inorganic compounds of bone and teeth replaced by minerals from ground water/soil and turning bones and teeth to stone
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uniformitarianism
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geological processes that occurred today also occurred in the past
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Principle of Original Horizontality
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Rock is layed down parallel to earth's surface (horizontal), and any alteration is present because of later activity.
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Principle of Superpositions
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Older layers on bottom, new ones on top.
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Principle of Cross-Cutting Relationships
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If any geological layers are cutting through layers (going diagonal), the diagonal one must be newer than what it cuts through.
==/== |
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Principle of Faunal Succession
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Sedimentary rock strata contain fossilized flora and fauna, and these fossils succeed each other vertically in a specific, reliable order that can be identified over wide horizontal distances
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Within site chemical techniques
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Look at chemical signals, uptake of elements through time (flourine, uranium, and nitrogen)
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Cenozoic
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past 65 million years
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environmental reconstruction techniques
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1) oxygen isotopes
2) ancient soils (dry vs. humid) 3) Vegetation-plant macrofossils (fossil pollens, phyloliths) 4) Stable carbon isotope ratios (reconstruct types of vegetation present) |
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oxygen isotopes (environmental reconstruction)
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Colder times - ration of 18O to 16O increases both in sea water and in shells of animals
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C3 plants (stable carbon isotope ratios)
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Trees, shrubs, most plants
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C4 plants (stable carbon isotope ratios)
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Tropical grasses (<1% of plants)
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CAM plants
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Cacti, agave (4% of plants)
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Paleocene Epoch
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65 - 55 mya, plesiadapiforms
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angiosperm coevolution model
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primates evolved to be seed-dispersers, eat fruit, etc.
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angiosperm
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flowering plants
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Eocene Epoch
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54 mya, first "true" primates. Adapoids and Omomyoids
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Oligocene Epoch
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34 - 24 mya. Fayum depression in Egypt. Parapithecidae, oligopithecidae, propliopithecidae.
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Parapithecidae
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Oligoscene epoch. Predates NWM and OWM split. Small, AQ, 3 premolars, insects and fruits.
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Oligopithecidae
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Oligoscene epoch. Mix of primate and derived features. Small. arboreal, insectofrugivores
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Propliopithecidae
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2 premolars, bit larger, slow arboreal climbers, leaf-eaters. Aegyptopithecus. Probably ancestral to catyrrhines.
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Dental apes
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23 mya, 5-rounded molar cusps (y5 fissure)
1) proconsul 2) Gibbon-like fossils in China 3) Sivapithecus in Pakistan (relative of orang) 4) Gigantopithecus |
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Proconsul
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20 - 18 mya, large bodied, no tail
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African ape (homonidae) ancestors
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1) Kenyapithecus - 14 mya, may have knucklewalked
2) Semburupithecus - teeth? |
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adapting to bipedalism: vertebral column and skull
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1) spinal curvature
2) Size of distal vertebrae 3) Placement and orientation of foramen magnum 4) Attachment of nuchal plane |
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adapting to bipedalism: vertebral column and skull: spinal curvature
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C-shaped in nonhuman primtates, not good for balance! S-shaped in humans, more even distribution of weight over two legs
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adapting to bipedalism: vertebral column and skull: size of distal vertebrae
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More weight balancing on our vertebral column. Lumbar and sacral vertebrae are enlarged.
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adapting to bipedalism: vertebral column and skull: placement and orientation of foramen magnum
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Moved more centrally located at bottom of skull, hold head upright
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adapting to bipedalism: vertebral column and skull: attachment of nuchal plane
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more flattened and angled in quadrupeds. On the bottom of skull in humans.
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adapting to bipedalism: pelvis and birth canal
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1) iliac blades shorter, shifted toward front
2) widening of subpubic angle 3) shorter pubic synthesis 4) larger acetabulum, closer to midline and under body 5) broader sacrum 6) gluteus minimus and medius muscles (stabilizes body over legs while walking) 7) gluteus maximus (stabilizes trunk over pelvis) |
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adapting to bipedalism: lower limbs
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1) enlarged femur in humans, changes centre of gravity
2) enlarged lateral lip of patellar groove 3) enlarged distal femur (to hold more weight) and top of tibia 4) lengthening of lower limb - later development 5) head and neck of femur thickened 6) angled to make foot land under center of gravity |
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adapting to bipedalism: FOOT.
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a) enlarged and rotated (non-opposible) big toe (for pushing off)
b) thicker metatarsels and phalanges c) shortened phalanges (other toes not used as much d) 2 arches in foot (longitudinal and transverse), act as shock absorbers, reduce fatigue fractures |
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adapting to bipedalism: ARM
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IT'S NOT INVOLVED! IT'S JUST NOT INVOLVED!
a) shortened and MUCH weaker compared to lower limbs b) broadening of tip of fingers ("tufting"), very efficient for pinching and grabbing c) wicked opposable thumb |
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tufting
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broadening of the top of fingers, makes for easier pinching and grabbing
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"Man the Ham" Model
..."man the hunter". |
Bipedalism evolved to make us more efficient hunters/give other limbs freedom to use tools. BUT, evidence shows that we scavenged for already-dead animals instead.
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Energetic Efficiency Model
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Bipedal walking is more efficient than knucklewalking. BUT, was our common ancestor a knucklewalker?
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Really Big Grass Model
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Increasing grasslands, standing up more efficient to see over grass. BUT, early humans were only like four feet tall, and savanna grasses are like six feet tall. Also, just as efficient to be a quadruped and stand up every once in a whie
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Solar Radiation Model
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It's fuckin' HOT in Africa! Only your head and shoulders are exposed to sunlight with bipedal. With quadruped, whole back is exposed. Also, cooler/more winds at higher altitudes. (overheating head --> cooling mechanisms)
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Thermoregulation Model
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Easier to dissipate heat when you stand upright.
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Postural Feeding Model
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Stand upright to reach fruit
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Lovejoy Model
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Early humans were monogomous. Males needed to provision females. Female stands, conceals signals of fertility.
problems: most likely not monogomous, and more likely that chimps gained the sexual swellings |
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Social Display Model
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Males stood up to show dominance. Females could more easily evaluate males.
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Technical intelligence
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Tool use and problem solving skills to extract food, etc. problem: No tools for first 3.8 million years.
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Ecological intelligence
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Mental map of where to find the best fruit trees, etc. problem: Other animals living in these environments too!
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Social intelligence
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Need more intelligence to live in large groups. Hay una relación entre neocortex size y group size. Theory of mind. problem: orangutans are solitary!
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Difference between hominid and hominin, OTHER than bipedalism.
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1) shape of dental arcade (more parabolic in hominins
2) Reduction in canine and incisor size (reduction in arch length) 3) Increase in postcanine dentition (premolars + molars) 4) Degree of prognathism 5) CP3 complex 6) Enamel gets thicker 7) Decrease in cranial cresting in hominins |
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Date of chimp/human divergence
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10 - 6 mya (molecular evidence)
7 - 4 mya better fossil record |
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Sahelanthropus tchadensis
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7-6 mya, found in Chad
Thick browridge. Not that prognathic. Very small brain - looks like female gorilla. Heavily forested area. |
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Orrorin tugerensis
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6 mya, fragments of femur. Some bipedal traits, some quadrupedal traits. Large canines, but thicker enamel.
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Ardipithecus ramidus
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4.4 mya. Found in dense forest area of Ethiopia. Reduced canines. Some skull aspects suggest more anterior foramen magnum.
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Ardipithecus ramidus kadabba
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Should be elevated to own species? 5.8 to 5.2 mya
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Australopithecines
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First species are DEFINITELY humans. Two types, "robust" and "gracile"
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Robust australiopithecines
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Also called "Patanthropus". Postcanine dentition and zygomatic arch are ENORMOUS. Crunched very hard nuts.
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Gracile australopithecines
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More like modern humans
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Australopithecus afarensis
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3.9 - 2.9 mya
"Lucy" intermediate dental traits, chimp-sized brain CLEARLY bipedal Laetoli footprints Pronounced sexual dimorphism - not monogomous |
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Australopithecus anamensis
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4.2 - 3.9 mya
tibial evidence - top is very thick and flattened. Thick enamel, BUT cp3 complex. Streamside forest. |
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Kenyathropus platyops
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3.5 mya
Very flat face |
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Australopithecus gachi
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2.5 mya. Found close to earliest stone tools. Cut marks on bones, evidence that carcases were butchered with tools.
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Australopithecus (P.) aethiopicus
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Robust australopithecine. 2.27 - 2.5 mya. Has sagittal crest, prognathic face, flared zygomatics, and huge molars. Small-brained. Could be evolutionary link between realy trunk of hominid family tree and specialized branch that led to robust australopithecines.
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Australopithecus (P.) boisei
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2.3 - 1.2 mya. Brain size same as other robusts from South Africa. Postcranial skeleton isl large. Reflects the suite of masticatory adaptations.
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Australopithecus (P.) robustus
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2.0 - 1.5 mya. Forward location of foramen magnum. Suite of masticatory characteristics. Ate substantial quantities of animal protein. Probably insects. Used bone tools to dig for termites.
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