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47 Cards in this Set

  • Front
  • Back
two stages of evolution of life
- development of first single cells
- development of complex and diverse life
organic evolution
concept that life has changed over the vast span of geological time (widely accepted)
Fossil trends
- single celled organisms oldest
- complex organims first to appear as impressions
- marine invertebrates are first then vertebrates
- vertebrates first in ocean, then appear on land
fossil species
a species is born, matures and dies(becomes extinct), more than 99.99% have
Dollo's law
once extinct, a species can never return to life on earth. extinction is forever
The genetic record
every modern organism comes w/in itself a molecular record of evolution from ancient single-celled organisms
The Anatomical Record
Physical structures w/in organisms provide proof of organic evolution
Vestigal organs
internal features that serve little or no useful function, but they are there (evolution proof)
Miller-Urey experiments
showed that this early atmosphere could make amino acids if electrical charges are applied
"Primordial soup"
nickname for early ocean with abundant amino acids, the building blocks of protein
Extremophile Record
1) at midocean ridge vents: take enrgy from Earth's internal heat, not the Sun
2) deep w/in the earth: live in rocks and draw energy from decomposing minerals
Charles Darwin
- The Orgin of Species (1859)
- The first person to convincingly show natural selection was a way to achieve organic evolution
- Natural selection is a gradual slow process that changes populations over time
Natural Selection
- Every population contains genetic diversity
- Not as controlled nor as rapid as artificial selection
any structure, process or behavior that helps an organism survive and thus pass on its genetic material
Age of Prokaryotes
~3.5 bya to 1 bya
the Monera, all single-celled organisms w/o a cell nucleus (DNA is coiled near the center of the cell)
Most important of the prokaryotes bc they conduct photosynthesis and release oxygen as a by-product (responsible for oxugen buildup in atmosphere)
Age of the Eukaryotes
1 bya to 0.7 bys
more advanced single-celled organisms beginning with a symbiotic relationship b/t cells; cells began live in other cells, thus eukaryotes formed
Age of the Ediacarans
700 mya to 545 mya
soft-bodied metazoans (multi-cellular) that are known only by their impressions left in sedimenteary rock; show adaptive radiation
Age of Shelly Life
570 mya to 465 mya
Cambrian Explosion
the apparent "sudden" appearance of marine invertebrates bearing shells and other body armor in fossils
Age of Fishes
~465 mya to 365 mya

began with jawless fish and evolved to cartilaginous then armored fishes, ended with amphibians
Age of Land Plants and Insects
~400 mya to present
Coal Age
Seeded plants were abundant and the first forests of trees developed, then there were abundant forest swamps (by 275 mya)
Age of Amphibians
~355 mya to 290 mya
Age of Reptiles
~290 mya to 65 mya

began with giant sail-back reptile and ended with dinosaurs
Age of Mammals
~65 mya to present
- vast spans of geological time representing major changes in Earth's fossil record

Phanerozoic - "visible life"
Proterozoic - "before life"
Archean - "early time"
Hadean - "primordial time"
- intermediate spans of geological time represening significant changes in Earth's fossil record

(look at table)
subdivisions of Eras

(look at table)
subdivisions of periods

(look at table)
"heavy bombardment" of meteorites and asteroids; molten crust; impact that formed the moon
life begins in "primordial soupp;" time of the prokaryotes
prokaryotes and eukaryotes; oxygen build up in atmosphere; multicellular life begins w/Ediacarans; adaptive radiation of marine inverebrates
adaptive radiation of marine invertebrated w/external skeletons; shelly marine life (trilobites)
vast, warm shallow seas; age of the jawless fish; global glaciation; ends w/mass extinction #1
first land plants, insects, vertebrates
age of diverse fish; near end mass extinction #2 maybe from cosmic impact
age of great coal swamps and the amphibians; building of Appalachains
age of reptiles begins; Pangaea is forms; global glaciations; mass extinction #3
breakup of Pangaea; gulf of mexico formed; first dinosaurs. turtles, marine reptiles; first mammals; ends with mass extinction #4
epitome of the "dinosaur age"
time of vast chalk deposits (dead marine plankton); diverse dinosaurs; flowering plants; edns in mass extinction #5 due to asteroid or comet
rise of the mammals; first large mammals, including whales
diversification of mammals; global glaciations