Chapter 1 - Adaptation By Natural Selection Flashcards
adaptations
Components of an organism that interact to help it survive and reproduce
natural selection
Evolution by variation and selective retention
postulates of Darwin’s theory of adaptation
1) The struggle for existence
2) Variation in fitness
3) Inheritance of variation
the struggle for existence
The ability of a population to expand is infinite, but the ability of any environment to support populations is always finite
variation in fitness
Organisms within populations vary, in this variation affects the ability of individuals to survive and reproduce
inheritance of variation
Variations in individuals are transmitted from parents to offspring
morphology
An organisms size, shape, and composition
stabilising selection
An organism reaches equilibrium with its environment, thus causing offsprings’ traits to be selected for constancy
traits
Characteristics of an individual
species
Populations of varied individuals that may or may not change through time
individual selection
Adaptation results from the competition among individuals, not between entire populations or species
fecundity
The ability to produce offspring
continuous variation
Even distribution in the range of expression of various traits among individuals in a population
discontinuous variation
A number of distinct expressions of a trait exist among individuals with in a population, with no intermediaries
convergence
Evolution of similar adaptations in unrelated groups of animals
