Aim: How does adaptative variation lead to the survival of an organism? Evolution 2
______________ (in structure and or behavior) within a population I. Variations: ______________ (in structure and or behavior) within a population DIFFERENCES
II. What produces variations? ______reproduction -____________ of genes ____________during Independent assortment – different ________ made by one parent ____________ Sexual recombination Crossing over Meiosis gametes Mutations
III. Why are variations important to a population? Variation in a species increases the chances that some members will ____________ _______________ Why is this important? survive an environmental change.
The peppered moth example:
A _________ that allows an organism to _________ in it’s environment IV. Adaptation A _________ that allows an organism to _________ in it’s environment variation survive
A variation that allows you to survive a ____________________ V. Adaptive Variation A variation that allows you to survive a ____________________ changing environment
VI. What would happen to a population with variation if the environment changed? Those who had an adaptive variation would_______ . Those that don’t will______. This would lead to …. survive die EVOLUTION
VII. What would happen to a population that did not have variation? If they don’t possess a ____ that allows them to adapt to a changing environment, they will _____ out: trait die EXTINCTION
Summary Questions: 1) The diagram below illustrates the change that occurred in the physical appearance of a rabbit population over a 10-year period. Which condition would explain this change over time? (1) a decrease in the mutation rate of the rabbits with black fur (2) a decrease in the advantage of having white fur (3) an increase in the advantage of having white fur (4) an increase in the chromosome number of the rabbits with black fur
2) Which statement concerning the evolution of species A, B, C, D, and E is supported by the diagram to the right? (1) Species B and C can be found in today’s environments. (2) Species A and D evolved from E. (3) Species A and C can still interbreed. (4) Species A, B, and E all evolved from a common ancestor and all are successful today.
3) The diagram to the right represents a woolly mammoth, a relative of the modern elephant. Woolly mammoths lived during the Ice Age and eventually became extinct. State one possible reason this species died out. *predation, overhunting, environment, competition