Transcript Evotheory1
Evolutionary Paradigm PARADIGM- set of assumptions about the nature of the phenomena to be studied and how it will be approached. An accepted theoretical framework Evolutionary Theories • Natural Selection Theory • Sexual Selection Theory • Sociobiological Theory Natural Selection Theory Understand the basic principles of Natural Selection •Know some examples of NS in action •Understand terms Individuals within a species vary Behavioral variation 50 45 40 35 Run Vocalize freeze Move low Mob 30 25 20 15 10 5 0 Predation response Traits are heritable Behaviors related too... • More offspring will be produced than will survive (drives competition) • Individuals with favorable traits will have an advantage over others without those traits. • Survival is dependent on context • Those that survive will produce more offspring. VI. Some examples • Peppered Moth Modern Day Finches Directional Selection Behavioral changes Unit of selection • Natural Selection works on the level of the individual. • Evolution works on the level of the population Sexual Selection Sexual Selection • The differential ability of individuals to acquire mates- features evolve, not to enhance survival but to make one more attractive to a mate and compete for access to mates. •Male male competition •Female choice Sociobiology • “the systematic study of the biological basis for behavior” E. O. Wilson – Reproductive success- number of offspring produced. – Genetic fitness- the relative contribution of one’s genes into the next generation TERMINOLOGY • Natural Selection- mechanism of evolutionary change for survival. Evolution- changes (genetic) within populations. • Sexual Selection- mechanism of evolutionary change for reproduction (mate choice, competition). • Sociobiology-theory that states that behavior has a biological basis, behaviors can function as adaptations to improve overall reproductive success of an individual. More Terminology • Reproductive success- # offspring one produces that reaches reproductive age. • Fitness- an individual’ relative genetic contribution to the next generation. • Adaptation- functional response of an organism to it’s environment. • Selection Pressure-environmental forces that influence the Reproductive Success of an individual.