UNIT 7 PART 1 Flashcards
Natural Selection
The process where organisms with favorable traits survive and reproduce more successfully
Population
A group of individuals of the same species living in the same area
Charles Darwin
Developed the theory of evolution by natural selection
Carolus Linnaeus
Created the system of taxonomy (classification of organisms)
Erasmus Darwin
Charles Darwin’s grandfather; early supporter of evolutionary ideas
Lamarck
Proposed that organisms evolve through the use and disuse of traits (incorrect theory, acquired characteristics, giraffes)
Charles Lyell
Geologist who argued that Earth’s processes occur gradually over time (tectonic plates, purposed idea to Darwin)
Convergent Evolution
When unrelated species evolve similar traits due to similar environments
Alfred Wallace
naturalist who developed the theory of natural selection independently of Darwin, influencing Darwin to publish his work
Competition
The struggle between organisms for resources
Adaptation
A trait that increases an organism’s survival and reproduction (positive mutation)
Fitness
An organism’s ability to survive and reproduce
Variation
Differences in traits within a population
Artificial Selection
Human-driven breeding of organisms for desired traits
Peppered Moth
A famous example of natural selection due to industrial pollution
Common Ancestor
An ancestral species from which multiple species evolved
Microevolution
Small genetic changes in a population over time
Macroevolution
Large-scale evolutionary changes that create new species
Evidence of Evolution
Observations that support evolutionary theory (fossils, anatomy, DNA)
Fossil
Preserved remains of past organisms
Common Descent
The idea that all organisms share a common ancestor
Transitional Fossil
Fossils showing intermediate forms between species
Endemic Species
Species found only in one specific geographic area
Homologous Structures
Similar structures in different species due to common ancestry
Analogous Structures
Structures with similar functions but different evolutionary origins
Vestigial Structures
Structures that have lost their original function through evolution, no longer utilized
Embryology
The study of embryos to understand evolutionary relationships
Population Genetics
The study of genetic variation in populations
Allelic Frequency
The percentage of a specific allele in a population
Genotypic Frequency
The proportion of different genotypes in a population
Hardy
Weinberg Equilibrium - A condition where allele frequencies remain constant unless acted on by evolutionary forces
H/W Law
The mathematical principle that predicts allele frequencies in non-evolving populations
Gene Pool
The total genetic material of a population
Sexual Selection
A type of natural selection based on traits that improve mating success
Immigration
Movement of individuals into a population
Emigration
Movement of individuals out of a population
Genetic Drift
Random changes in allele frequencies due to chance
Bottleneck Effect
A sharp reduction in population size that reduces genetic diversity
Founder’s Effect
When a new population is started by a few individuals, leading to reduced genetic diversity
Stabilizing Selection
Favors the average traits, reducing variation
Directional Selection
Favors one extreme trait, shifting the population
Disruptive Selection
Favors both extremes, leading to two distinct groups
Heterozygote Advantage
When heterozygous individuals have higher fitness than either homozygote
