ARCH 131 Lecture Notes - Lecture 4: Thomas Robert Malthus, Wood Bison, Plains Bison
2 Jun 2015
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Introduction to evolution: natural selection is a theory , but evolution is a fact. 1. more offspring are produced by a species than can be supported by naturally avalible food sources: 1798 , thomas malthus animal population increase exponentially while food supplies tend to remain stable . 2. within any one species there exists a significant amount of biological variability: since only a portion of all offspring will survive to reproduce. Fitness, refers to the differential reproductive success of individuals within a species: over long periods of time, accumulated changes within a species will eventually result in new species. 5 premise of evolution: a species reproduce more than it can sustain, within any one species. Tiger , their color of their pelt allows them to blend into tall grass, and jungle to allow them to sneak up and kill preys. However, if the environmental changes, their pelt becomes less advantages. ( yellow tigers don"t survive well in white stone environments)
