ANTH 1010H Chapter Notes - Chapter 5: Hemoglobin, Tachycardia, Genetic Drift
Document Summary
Science: a theory is based upon a hypothesis and backed by evidence: a fact-based framework for describing a phenomenon. Gene frequencies change in every generation, evolution occurs continuously. Theory of evolution by natural selection: more individuals than can survive, variation exists, limited resources, adaptation to environment leads to differences in reproductive success, change in gene frequencies, accumulated change. For natural selection to occur, traits must be: Heritable cannot be acquired (eg. giraffe"s neck) Variable variation must exist in population. Individuals with features that are best suited to their environment are more likely to pass on their genes in the greatest number. Crucial factor in evolutionary process is an ecological factor: the fit between organisms and their environment. Occupy virtually all ecosystems: habitats (area where we live, niches (way of living, humans dominate ecosystem, development of tools. Use of technology allows us to have very different lifestyles: similar to speciation and niche formation in other animals.