Natural Selection and Evolution Concepts

Flashcards covering key vocabulary related to Natural Selection, Evolution, and Speciation.

Natural Selection

The process where organisms better adapted to their environment tend to survive and produce more offspring.

Survival of the fittest

A phrase that describes how individuals that are better adapted to their environment are more likely to survive and reproduce.

Selection Pressure

External factors that affect an organism's ability to survive and reproduce.

Microevolution

Evolution occurring on a small scale, often observed as changes in allele frequencies in a population.

Phenotype

Observable physical and functional traits of an organism influenced by its genotype.

Genotype

The genetic makeup of an organism, comprising its set of genes.

Speciation

The process through which new species arise from existing populations.

Allopatric Speciation

Speciation that occurs when populations are geographically isolated.

Sympatric Speciation

Speciation that occurs without geographic isolation, often through mechanisms such as polyploidy.

Adaptive Radiation

An evolutionary pattern in which an ancestral species rapidly diversifies into a variety of forms to adapt to different environments.

Vestigial Structures

Remnants of organs or structures that had a function in an early ancestor but are reduced or no longer serve a purpose.

Artificial Selection

The intentional breeding of certain traits or combinations of traits over others by humans.

Hardy-Weinberg Equilibrium

A principle stating that allele and genotype frequencies in a population remain constant from generation to generation in the absence of evolutionary influences.

Genetic Drift

Random changes in allele frequencies in a population, which can lead to reduced genetic diversity.

Bottleneck Effect

A sharp reduction in population size due to environmental events or other pressures, leading to decreased genetic variability.

Hybrid Inviability

A condition where interspecific hybrids fail to develop properly and cannot survive.

Hybrid Sterility

A condition where hybrids are produced but are unable to reproduce.

Fossil Record

The total collection of fossils that provides evidence for the evolution of life on Earth.