- Plant species with large seeds produce fewer seeds than plant species with small seeds.
- Anolis lizards that had their ovaries surgically removed grew more over the next year than anolis lizards that had surgery but kept their ovaries.
- Trees with thicker growth rings produce fewer seed cones than trees with narrower growth rings.
- Unlike most species which die shortly after their last reproductive bout, Female orcas undergo menopause and live 30-40 years after their last reproductive event.
- The "good genes" hypothesis for sexual selection argues that elaborate traits come about because of strong preferences by femalesThe "good genes" hypothesis for sexual selection posits that males advertise their quality by having a costly trait (e.g., bright, showy ornaments)
- In exploitative competition, resource use by one species reduces the availability of that resource for another speciesIn interference competition, one species reduces exploitation efficiency of the other and will disrupt, weaken or kill other species.
- A mass extinction is identified when extinction rates are significantly elevated over background extinction ratesThe increase in the number of megaguilds over time suggests that species have gotten more efficient at partitioning their niches over time and that "ecospace" has become more tightly packedSpecies with a lifespan that spans many millions of years are called living fossils (e.g., Ginkgo and horseshoe crab)
- The plant, Lupus nanus, lives only one year and invests 26% of its energy in reproduction. The plant, Lups arboreus, lives multiple years and invests 7% of its energy in reproduction each year.
- An Elvis taxon disappears from the fossil record only to reappear later
- Niche partitioning increases overlap in resource useEcological sorting results in multiple species occupying a single niche
- Extreme or exaggerated traits in males are typically not heritable
- Human hunter-gatherer societies with a higher fertility rate have smaller offspring at age 5 than societies with a lower fertility rate
- Peccaries like to eat spiny cacti with few spines, reducing the fitness of individuals with low spine density. A parasitic insect lays its eggs at the base of spiny cactus spines. The insect bores into the cactus and eats the insides, reducing the fitness of individuals with many spines. What type of selection is operating on the spine density trait?
- The term "Mullers ratchet" describes the process where by deleterious alleles can accumulate faster in sexual populationsThe heritability of a trait should be the same regardless of whether is is measured in the wild or in the labh2, narrow-sense heritability, is the proportion of phenotypic variance explained by additive, epistatic, and dominance effect on traits
- Males dancing or displaying to females is an example of intrasexual selectionFishers runaway sexual selection argues that elaborate traits come about because of strong preferences by femalesSexaul cannibalism (when a femal eats her mate) is selected for because most males have reached the end of their life just before mating anyway
- Polar bears and grizzly bears sometimes interbreed in nature in areas of sympatry. When they do, their offspring are poorly adapted due to their intermediate phenotype.
- A monophyletic group is one that includes a common ancestor, but not all of its descendantsThe difference between a phylogeny and taxonomy is that a taxonomy clarifies evolutionary relationships
- Sperm competition is an example of intrasexual (ex male-male competition selection)Anisogamy is when males and females have gamete of unequal sizeA positive correlation between a trait and mating success is evidence of sexual selection
- Red and purple sea urchins live in the same communities and release their gametes at the same time. Their gametes are incompatible and hybridization does not occur.
- A rapid divergence of species from a common ancestor that fills multiple niches is called an adaptive radiationIn an adaptive radiation the origination rate exceeds the extinction rate