#extinction rates

MOLECULAR EVOLUTION

Van Valen’s law states:

Extinction probability remains constant reflects key principle in quiz on molecular evolution pyqs solved -sec d, where evolutionary mechanisms shape genetic variation and adaptation. In this context, Extinction probability remains constant aligns with experimental and theoretical evidence from population genetics, behavioral ecology and molecular phylogeny. Textbooks like Campbell Biology, Futuyma Evolution and Hartl Principles illustrate supporting data. Understanding why Extinction probability remains constant fits helps integrate natural selection, drift and species concepts essential for

Ref: Nei & Kumar, Molecular Evolution, Clocks and Purifying Selection.

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Biogeography Complete

Larger islands tend to have lower extinction rates because they have:

“More available resources” for larger islands tend to have lower extinction rates because they have. This relationship follows from the ecological mechanism represented by the terms in the item, not merely from an association between their names. Larger islands usually support more habitats and larger populations, lowering extinction risk; less isolated islands receive colonists more readily and may experience rescue effects. These mechanisms also apply to habitat fragments that function as ecological islands. The remaining alternatives—“More competition”, “Higher immigration rates”, “Less spe

Ref: Biogeography, Lomolino et al., 5th Ed., Ch. 5-8

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Biogeography Complete

Why does a new, empty island initially have low extinction rates?

“Abundant resources and low competition” for why does a new, empty island initially have low extinction rates. This relationship follows from the ecological mechanism represented by the terms in the item, not merely from an association between their names. At equilibrium, species identities can continue to turn over even when richness is approximately stable. The model predicts a balance of rates, not an absence of colonization or extinction. The remaining alternatives—“High competition”, “High predation pressure”, “Small space”—refer to different states, processes, or scales and therefore do

Ref: Biogeography, Lomolino et al., 5th Ed., Ch. 5-8

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Biogeography Complete

Which factor greatly influences extinction rates on islands?

“Island size” for which factor greatly influences extinction rates on islands. This relationship follows from the ecological mechanism represented by the terms in the item, not merely from an association between their names. At equilibrium, species identities can continue to turn over even when richness is approximately stable. The model predicts a balance of rates, not an absence of colonization or extinction. The remaining alternatives—“Island vegetation”, “Island shape”, “Island altitude”—refer to different states, processes, or scales and therefore do not express the same causal relationsh

Ref: Biogeography, Lomolino et al., 5th Ed., Ch. 5-8

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Island

Small islands typically have:

“Higher extinction rates” for small islands typically have. This relationship follows from the ecological mechanism represented by the terms in the item, not merely from an association between their names. Larger islands usually support more habitats and larger populations, lowering extinction risk; less isolated islands receive colonists more readily and may experience rescue effects. These mechanisms also apply to habitat fragments that function as ecological islands. The remaining alternatives—“Lower extinction rates”, “Higher immigration rates”, “Increased species richness”—refer to differ

Ref: The Theory of Island Biogeography, MacArthur & Wilson, Ch. 2-4

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Extinction Topic

Habitat destruction causes what percent of extinctions?

“0.36” for habitat destruction causes what percent of extinctions. This relationship follows from the ecological mechanism represented by the terms in the item, not merely from an association between their names. Extinction risk rises when abundance, geographic range, or genetic variation becomes small because demographic chance, environmental fluctuations, inbreeding, and rare catastrophes then have disproportionate effects. Correlated losses among subpopulations further weaken regional persistence. The remaining alternatives—“0.23”, “0.434”, “0.38”—refer to different states, processes, or sc

Ref: Conservation Biology, Primack & Sher, 6th Ed., Ch. 7

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