ARCH 131 Lecture Notes - Lecture 3: Wood Bison, Grandmother Hypothesis, Guppy

• School: Simon Fraser University
• Department: Archaeology
• Course: ARCH 131
• Professor: Dennis Sandgathe

Document Summary

Fundamental premises of natural selection (these processes can be factually proven and so can prove the existence of evolution) More offspring are produced by a species that can be supported by naturally available food sources (i. e. not all accord become oak trees, not all calves become cows etc. ) Thomas malthus noted that animal populations tend to increase exponentially while food supplies tend to remain stable. Within any one species there exists a significant amount of biological variability. Since only a portion of all offspring will to reproduce, those with advantageous traits will have an edge over other members of their species. Those individuals with traits that will increase their chance of living longer are more likely to reach the age at which they will begin reproducing and so are more likely to contribute offspring to subsequent generations. Those traits that are advantageous under current environmental conditions will tend to be passed on.