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11 Cards in this Set
- Front
- Back
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What are the 3 parts of biodiversity?
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1. Species
2. Genetic Diversity 3. Ecosystem |
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How do species contribute to biodiversity?
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-Richness= # of species
-Evenness= distribution of spcies |
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How does genetic diversity contribute to biodiversity?
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-Heterozygosity= # of alleles, want more (Aa)
-Genetic drift= leads to more homozygous, bottle neck or Founder events -More hetero can evolve better and are more stable and less resistent |
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How do ecosystems contribute to biodiversity?
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Diversity within ecosystem based on habitats, food webs, ect.
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What are today's species estimates as compared to those 40/50 years ago?
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-40/50= 3 to 5 million, but in 1980s Erwin fumigated trees to get insects and estimated 30 mil arthropods
-1990s= 100 million, know 1.8 million named -2011= 8.7 million total |
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What happened in the Ordovician extinction?
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-Oldest, 440 mya
-95% marine species extinct -Caused by glaciation which resulted in lower sea levels |
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What's a taxa?
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Group of related organisms, i.e. a family, phylum, or genus.
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What happened in the Devonian extinction?
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-365 mya
-95% shallow aquatic species -Cause is unknown |
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What happened in the Permian extinction?
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-245 MYA, longest
-90% marine inverts., 50% marine families -Causes: unknown, but theories say impact or increase of volcanic activity |
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What happened in the Triassic extinction?
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-200 MYA, age of dinosaurs
-Loss of Ammanites, 20% marine organisms -Due to increase CO2, volcanic activity |
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What happened in the Cretaceous extinction?
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-65 MYA
-Discovered by K-T boundary fossils -80% marine inverts., reduction in mammals, dinosaurs except birds -Cause= metiorite |
