BIO 200 Lecture Notes - Lecture 4: Medium Ground Finch, Vincetoxicum, Powelliphanta
27 Jun 2015
School
Department
Course
Professor
Document Summary
Individuals vary: populations overbreed, leading to competition, survival of the fittest (better traits lead to better survival, survivors are more likely to reproduce, traits that cause certain individuals to survive must be heritable (passed to offspring) Individual variation: self-evident (look outside, examples: powelliphanta (land snails) and vincetoxicum rossicum (dog strangling vine, different colors, shapes, sizes, etc. Overbreeding and competition: not all offspring survives into adulthood, example: quercus sp. (oak trees) acorns have a 0. 01-0. 1% survival rate. Survival of the fittest: rosemary and peter grant studied geospiza fortis (ground finches) on the galapagos island of daphne major, observed obvious variations of plumage color, overall size, and beak size. 1977: severe la ni a (drought: only large, hard seeds were available, more finches with large beaks survived. Age of the earth: hutton and lyell believed that the earth was extremely old, and had influence in the scientific community, thickness of rock strata in deep canyons indicates very long and gradual processes.
