Chapter 7: Primate Evolution Flashcards
taphonomy
the study of what happens to the remains of an organism after death
provenance
the original location of a fossil or artifact
relative dating
a method of dating that identifies objects as being younger or older than other objects
absolute (chronometric) dating
a method of dating that assigns a specific age and estimated error to a fossil or site (e.g., 1.6 plus/minus 0.23 million years)
dating error
the degree to which a date derived from an absolute or relative technique differs from the actual date
stratigraphy
the study of the different layers (strata) that have been deposited over time
biostratigraphic dating
a method of relative dating that involves dating a fossil based on associated faunal remains that have been securely dated using other methods
fluorine dating
a method of relative dating that involves comparing the amount of fluorine that has accumulated in fossils found at the same site
paleomagnetism
a method of relative dating that involves comparing reversals in the earth’s magnetic field
radioactive isotopes
unstable isotopes that decay, emitting radioactivity
radiometric dating
an absolute method of dating based on the radioactive decay of isotopes
carbon-14 (radio-carbon dating)
a method of absolute dating based on the radioactive decay of carbon-14 into nitrogen-14
half-life
the amount of time it takes for half of an existing quantity of radioactive material to decay
accelerator mass spectrometry (AMS) dating
a method of radiocarbon dating used to date very small samples
potassium-argon dating
a method of absolute dating based on the radioactive decay of potassium (40K) into argon gas (40Ar)
argon-argon dating
a method of absolute dating that measures the isotopic ratio of 40A to 39A
fission-track dating
a method of absolute dating that involves counting the number of tracks produced by the decay (fission) of the uranium isotope 238U contained in certain kinds of rocks
uranium-lead dating
a method of absolute dating that looks at the radioactive decay of uranium0238 to lead-206 and uranium-235 to lead-207 in minerals
uranium-series dating
a method of absolute dating that looks at the decay of uranium-234 to thorium-230 in calcium carbonate materials
electron spin resonance (ESR)
a method of absolute dating that involves measuring electrons trapped in materials such as teeth
thermoluminescence (TL)
a method of absolute dating that involves measuring the amount of light produced by the release of electrons trapped in objects such as stones and ceramics when they are heated
optically stimulated luminescence (OSL)
a method of absolute dating that involves determining the last time mineral grains such as quartz or feldspar were exposed to daylight by using light to measure the amount of energy trapped in the minerals’ crystals
cosmogenic nuclide dating
a method of absolute dating that looks at the ratio of aluminum-26 to beryllium-10 in quartz sand crystals
geologic time scale
the division of the earth’s geologic events into time periods such as eras and epochs
Cenozoic era
the geological era in which mammals, including primates, evolved
epoch
a measure of geologic time that partitions geologic eras (e.g., Cenozoic) into smaller units, defined with regard to major climatological /environmental events
Pangaea
the original landmass made up of the seven continents we recognize today
continental drift
the movement of the plates that make up the earth’s continents
Laurasia
the landmass consisting of North America, Europe, and Ausia
Gondwanaland
the landmass consisting of South America, Africa, Antarctica, Australia, Madagascar, and India
biodiversity
variation in life forms within a given ecosystem
endemism
the state of being found exclusively in a particular place
paleoecology
the study of ancient environments
paleobotanists
specialists who study ancient plant remains
palynologists
specialists who study pollen
paleontologists
specialists who study the fossilized remains of extinct life forms
oxygen isotope analysis
the use of stable oxygen isotopes to reconstruct ancient climates; it can also be used to examine the geographic origins of organisms such as humans
stable isotopes
different forms of an element that have different atomic mass and that are not radioactive
crown group
the last common ancestor of a clade plus all of its descendants, including living members of the clade
stem group
a group of extinct organisms that are not part of the crown group
extant
still existing; commonly used to refer to living species
paleobiology
the study of the behaviour and ecology of fossil organisms
dental microwear
microscopic wear on the enamel surfaces of the teeth, primarily due to diet
shearing quotient
a measure of the relative shear potential of molar teeth
occlusal
the chewing surface of a tooth
Paleocene
the first epoch of the Cenozoic era, dating from about 66 to 56 Ma
plesiadapiforms
a group of primate-like mammals that lived during the Paleocene epoch
procumbent
forward-projecting
Eocene
the second epoch of the Cenozoic era, dating from about 56 to 34 Ma
omomyids
tarsier-like primates from the Eocene epoch
adapids
lemur-like primates from the Eocene epoch
Notharctus
an Eocene primate of the family Adapidae
basal anthropoids
the earliest anthropoids
Oligocene
the third epoch of the Cenozoic era, dating from about 34 to 23 Ma
Fayum
a fossil-rich region of Egypt once home to many Oligocene anthropoids
oligopithecids
early anthropoids from the Oligocene epoch
parapithecids
a group of early anthropoids from the Oligocene epoch
propliopithecids
the largest group of the Oligocene anthropoids
Aegyptopithecus
a propliopithecid from the Oligocene epoch
Y-5 pattern
cusp pattern formed by 5 cusps on the lower (mandibular) molar teeth in hominoids
floating island model
the hypothesis that the ancestors of New World monkeys rafted across the Atlantic from Africa to South America on floating islands of vegetation
Victoriapithecidae
the family to which the earliest Old World monkeys belong
bilophodont
molar teeth characterized by four cusps connected by two ridges of enamel
Miocene
the fourth epoch of the Cenozoic era, dating from about 23 to 5.3 Ma
proconsulids
early Miocene hominoids from Africa
Proconsul
the best-known genus of early Miocene hominoids
cingulum
a raised ridge of enamel found on the upper molar teeth
Dryopithecus
a genus of large-bodied hominoids that lived in Europe during the Miocene epoch
klinorhynchy
downward tilting of the face relative to the cranial base
Sivapithecus
a genus of large-bodied hominoids that lived in Asia during the Miocene epoch
molecular systematics
the use of molecular data to reconstruct the evolutionary history of early primates and determine the time of divergence of different species
molecular clock
a concept involving the use of molecular data to estimate the sequence and timing of divergence of various evolutionary lineages