Chapter 23

macroevolution

• broad changes above species level

• emergence of terretestrial vertebrates

• impact of mass extinctions

• origin of key adaptations

fossil record is a complete chronicle of evolution

• true

• false

the fossil record is in favor of species

• existed for a long time

• abundant

• widespread

• hard shells, skeletons, and other parts

relative age of fossils can be determined by

• radioactive isotopes

• sequence in rock strata

• placement of fossil in sedimentary rock

• radiometric dating

oldest known fossils, rocks formed by accumulation of sedimentary layers on bacterial mats

• radiometric dating

• half-life

• geologic record

• stromatolites

absolute age of fossils can be determined

• radiometric dating

• half-life

• geologic record

• stromatolites

time required for half parent isotope to decay (parent isotope decay to daughter isotope)

• radiometric dating

• half-life

• geologic record

• stromatolies

time-scale dividing Earth's history into four eons

• radiometric dating

• half-life

• geologic record

• stromatolite

(?) era is the most time animals have existed on Earth

• archean eon

• hadean eon

• proterozoic eon

• phanerozoic eon

paleozoic, mesozoic, and cenozoic

• eons

• eras

• boundaries are major extinction events

• boundaries are major speciation events