The objective of this chapter is to understand the mechanisms of heritable genotypic and phenotypic changes and their influence on evolution of groups of living organisms.
 | excess progeny (11-1) - unrestrained growth of hypothetical elephant population (Excess progeny); more offspring are produced than can survive to reproduce |
| variability - the characteristics of living things differ among individuals |
| heritability - many differences are the result of heritable genetic differences |
| differential adaptedness - some differences affect how well adapted an organism is |
| differential reproduction - some differences in adaptedness are reflected in the number of offspring successfully reared |
| random allelic fluctuation caused by chance; not influenced by relative adaptiveness of changed alleles |
4.4.1. crossing over
4.4.2. sexual recombination (11-2)
4.4.3. mutation (11-3) wisteria, mutation from lavender variety
2.5.1. point mutations
2.5.2. gene or exon duplication
2.5.3. exon recombination (11-4)
2.5.4. horizontal transfer of genes from other species
2.6.1. immigration and emigration (gene flow)
2.6.2. nonrandom mating
| Female-choice sexual selection in guppies (non-random mating)(11-5) |
| Female-choice sexual selection in guppies (non-random mating)(11-6) |
2.6.3. natural selection
2.6.4. mutation (11-7) replicate plating of penicillin resistant strain
2.6.5. genetic drift (11-8) Possible genetic drift in a cichlid fish
2.7.1. Operates by increasing reproductive fitness
2.7.2. Directional (favoring one end of a range of variation, e.g., % oil in corn kernels)
2.7.3. Stabilizing (favoring a certain value, e.g., horseshoe crab, environment has not changed)
2.7.4. Disruptive (favoring two, or rarely more values, e.g., birds with long and short beaks survive over those with intermediate)
2.7.5. Depends on the difference between trait's costs and benefits (11-10) incidence of Sickle Cell Anemia by region in Africa (homozygous individuals die; heterozygous individuals are more resistant to malaria).
commensalism - one species benefits, the other doesn't but is not harmed (11-14) anemone fish
mutualism - both species benefit
| a (11-15) giant seabass cleaned by cleaner fish |
| b (11-16) yellow-billed oxpeckers search for parasitic insects on a black rhinoceros |
parasitism (11-17) - tomato hornworm with pupae of parasitoid wasp; one species benefits, the other is harmed
4.1.1. Definition - group of organisms capable of reproducing but isolated from other populations reproductively.
4.1.2. Variation with species
18.4 (11-18) altitude variation of herb (Achillae lanulosa)
18.5 (11-19) two subspecies of Canadian goose havinging different breeding grounds and different ranges. A. U.S., B. Canada
4.2.1.1. model (11-20)
4.2.1.2. example of squirrels in Grand Canyon (11-21)
4.2.1.3. factors involved
| different initial gene frequencies |
| different mutations |
| different environmental selection pressures |
4.2.2.1. ecogeographic isolation
4.2.2.2. habitat isolation
4.2.2.3. seasonal isolation (11-22)
4.2.2.4. behavioral isolation (11-23)12 different species of fiddler crabs on the same beach in Panama could be distinguished by the display of waving their large cheliped, elevating the body, and moving around in their burrow
4.2.2.5. mechanical isolation (11-24), e.g. pollination of Scotch broom by a bumble bee; nectar is unavailable to lighter honeybees that cant trip release mechanism
4.2.2.6. gametic isolation, e.g. environment in female immobilizes sperm
4.2.2.7. developmental isolation, e.g. crosses between goats and sheep die before birth
4.2.2.8. hybrid inviability, e.g. hybrid offspring are weak and malformed
4.2.2.9. hybrid sterility, e.g. hybrid offspring are sterile
4.2.2.10. selective hybrid elimination, e.g. hybrid are less well adapted than parents
4.2.2.11. summary (11-25)
| beak differences in Hawaiian honeycreepers (11-29) |
| birds with short beaks eat small hard seeds; those with long beaks eat larger softer seeds) |
5.1. What is evolution? What role does natural selection play in evolution?
5.2. Briefly outline five factors which cause natural selection.
5.3. How do new genes arise?
5.4. How do mutations spread in populations?
5.5. Gives examples of adaptations for pollination, defense, and symbiosis.
5.6. Give definitions and examples of commensalism, mutualism, and parasitism.
5.7. What is the definition of species?
5.8. Discuss and understand in detail five factors which influence the process of speciation.
| adaptive radiation | analogous structure | stabilizing natural selection |
| comparative morphology | fossil | directional natural selection |
| homologous structure | lineage | macroevolution |
| mass extinction | exon recombination | phylogeny |
| morphological convergence | horizontal gene transfer | polyploidy |
| morphological divergence | hybrid inviability | mutualism |
| neutral mutation | commensalism | punctuation |
| evolution | natural selection | population |
| phenotype | Hardy-Weinburg Principle | alleles |
| genetic equilibrium | microevolution | mutation |
| genetic drift | gene flow | stabilizing selection |
| directional selection | divergence | disruptive selection |
| sexual selection | speciation | behavioral isolation |
| mechanical isolation | parasitism |
THE TREE OF LIFE - by David R. Maddison & Wayne P. Maddison, University of Arizona
Text tree sequence starting with Eubacteria, Archeabacteria, Eukaryotes, and Viruses, and continuing to all subcategories.Animal Diversity Web - University of Michigan Museum of Zoology "The Animal Diversity Web is a collection of pictures and information about animals. Accounts of individual species include information on distributions, natural history, conservation, and economic importance, along with pictures and sounds if available. Synopses of some higher taxonomic groups are also provided."
EVOLUTION - A. Fagen at Harvard Biolabs
Pointers to the WWWBiology and Estimation Vols 1&2 - J.B. Walsh, Univ. of Arizona
Genetic basis of quantitative traits, trait loci, estimation procedures, character evolution, single character selection response, multivariate selection, evolution models.
