Campbell Bio

Evolution

The process of change in species of organisms over time, including the patterns of change and adaptation within populations.

Primordial soup

The mixture of conditions on early Earth that scientists theorize led to the formation of life.

Miller-Urey Experiment

An experiment that demonstrated the formation of amino acids, suggesting that life could form under early Earth conditions.

Anaerobic heterotrophs

Simple organisms that rely on anaerobic processes for energy due to the lack of oxygen in the early atmosphere.

Aerobic heterotrophs

More complex organisms that can use oxygen to produce energy, evolving after oxygen became available in the atmosphere.

Natural selection

The primary mechanism of evolution where organisms better adapted to their environment tend to survive and produce more offspring.

Jean-Baptiste Lamarck

A scientist who proposed that organisms adapt through use and disuse of traits, which are then passed on to offspring.

Charles Darwin

Naturalist who developed the theory of natural selection based on his observations during the voyage of the HMS Beagle.

Speciation

The process by which new species arise due to evolutionary changes and adaptations to different environments.

Survival of the fittest

A phrase used to describe the mechanism of natural selection, where individuals better adapted to their environment survive and reproduce.

Mutation

Random changes in the genetic code that can lead to new traits in organisms and influence evolution.

Genetic drift

A mechanism of evolution that causes allele frequencies to change due to random sampling events in populations.

Carrying capacity

The maximum population size that an environment can sustain, affecting population fluctuations.

Adaptation

A trait that enhances an organism's ability to survive and reproduce in its environment.

Competition

The struggle between organisms for limited resources, which influences natural selection and evolution.

Extinction events

Intervals in Earth's history where a significant number of species go extinct within a relatively short period.

Allele frequencies

The relative frequency of different alleles of a gene in a population, which can change due to evolution.

Overproduction

The phenomenon where more offspring are produced than can survive, leading to competition and natural selection.