ch. 14: macroevolution Flashcards
Microevolution
evolution occurring within populations
*adaptive and neutral changes in allele frequencies
Macroevolution
evolution above the species level
*origination, diversification and extinction
Are species equally distributes over the globe?
no, tropical areas have more diverity in species
Biogeography
the study of the distribution of species across space and time
Alfred Russel Wallace
“Father of Biogeography”
-noticed this line of divide where one species is placental mammals and the other is marsupial mammals (islands right next to each other) -> known as Wallace’s Line
Biographical patterns explained by…
V - vicariance
E - extinction
D - dispersal
Interplay of ____ and ____ determines diversity
speciation, extinction
D1 (diversity) + originations - extinctions = D2 ( new diversity)
What are the three evolutionary faunas?
Cambrian, Paleozoic, Modern
Mass extinction can result from?
climate change
Diversity can decline when extinction ____ or origination ____.
increase, decreases
Adaptive Radiation
when a eclipses Ω
Why did the cambrian explosion occur?
ecology of ocean changes which gave rise to new species
*warming and retreat of glaciers
*oxygenation of ocean
Background extinction
the normal rate of extinction for a taxon or biota
Mass extinction
a statistically significant increase above background extinction rate
What are the Big Five?
*big five extinction that had difference causes that impacted different organisms
1. Ordovician Event: 1.9-3.3 million years ago
2. Devonian Event: within 2-29 million years ago
3. Permian Event: 60,000 years ago
4. Triassic Event: 600,000 to 8.3 million years ago
5. Cretaceous Event: 1 year to 2.5 million years ago