BIOL 290 Chapter Notes - Chapter 2.1-2.2: Gregor Mendel, Population Genetics
The importance of Evolution in Ecology
Monday, September 17, 2018
12:09 PM
• Two processes occurring together
• Ecologists study the processes that determine nutrient flow, community diversity, and population
size
• Evolutionary biologists study the processes that lead to adaptation and diversification of
populations and species
• Evolution can be startlingly fast
• Rapid Evolution
1. Pink Bollworms
• Multiply very quickly; must be killed with chemical insecticides; toxic to humans, expensive, kill
beneficial arthropods, and other crop pests
2. Threespine Sticklebacks
• Natural selection
1. The growth of an individual's suit of armor is predetermined; an individual fish cannot change it's
plates
2. Lack of change in individuals does not prevent the population from changing across generations
• Charles Darwin
• English naturalist; father was ashamed, tried to send him to medical school; darwin wasn't having
it; attempted to have him join the clergy; Darwin wanted to collect beetles; promising student of
natural history
• Botany instructor: John Steven Henslow; recommended darwin as companion on HMS BEAGLE:
came up with conclusions
1. earths organisms are descended with modification from common ancestors
2. The process responsible was natural seclection
• Assertions of Natural Selection:
1. Individuals Vary; This is important because if individuals do not vary, the population can not
evolve
2. Offspring Resemble their parents; if traits are not heritable, the population will not evolve
because offspring can not receive the traits
3. Survival and reproduction are selective
• Any population that satisfies the three assertions of the theory of evoluton by natural selection
will evolve.
• Darwin did not actually understand the mechanism responsible for variation and inheritence
• Basic rules of inheritance were worked out by Gregor Mendel
