Scientific Theories and the Theory of Evolution

These vocabulary flashcards cover the core concepts of scientific theory evolution, the history of evolutionary thought, mechanisms of natural selection, and evidence for evolution including fossil types and structural homologies.

Scientific Theory

A powerful, broad explanation of a large set of observations based on well-supported hypotheses and research from several independent sources.

Spontaneous Generation

A defunct predecessor to Cell Theory that was definitively refuted by Francesco Redi in 1668 and Louis Pasteur in 1859.

Geocentrism

An incorrect theory based on Ptolemy's measurements that placed Earth at the center of the solar system; it lasted 1,500 years because its calculations accurately predicted planetary positions.

Heliocentrism

The scientific theory that the sun is at the center of the solar system, theorized by Copernicus and proven 100 years later by Galileo through the phases of Venus.

Miasma Theory of Disease

The defunct predecessor to the Germ Theory of Disease.

Inheritance of Acquired Characteristics

A defunct predecessor to the theory of Evolution by Natural Selection.

Theory of Evolution

Proposed by Charles Darwin in 1859, it suggests that all species descended from a common ancestor and that evolution occurs through natural selection.

HMS Beagle

The ship on which Charles Darwin served as a naturalist starting in 1831, visiting locations including the Galapagos Islands.

Charles Lyell

An influential figure to Darwin who argued that geological features result from the gradual accumulation of small changes by everyday forces.

Adaptation

A heritable trait that aids the survival and reproduction of an organism in its present environment.

Adaptive radiation

The process where new species (speciation) are formed when one species radiates out to form several other species.

Population

A group of organisms of the same species living together in the same geographic area.

Overproduction

The principle of natural selection stating that species tend to produce more individuals than can survive to maturity, leading to competition for resources.

Natural Selection

The reproduction of individuals with favorable genetic traits that survive environmental change, leading to evolutionary change in a population.

Allele

A different form of a gene.

Fitness

An organism’s ability to survive and reproduce in a particular environment, influencing the likelihood of passing alleles to the next generation.

Sexual dimorphism

The phenotypic difference between a population's males and females.

Good genes hypothesis

A theory of sexual selection arguing that individuals develop impressive ornaments to demonstrate efficient metabolism or the ability to fight disease.

Handicap principle

A theory of sexual selection suggesting that only the fittest individuals can afford to maintain costly, burdensome traits.

Divergent Evolution

When two species evolve in different directions from a common point, often resulting in homologous structures.

Homologous structures

Anatomical features that share similarities because they result from evolutionary divergence from a common ancestor.

Convergent Evolution

When similar structures arise through evolution independently in different species rather than from a common ancestor.

Analogous structures

Structures that are similar in function and appearance but do not share an origin in a common ancestor.

Vestigial structures

Physical structures present in an organism that have no apparent function and appear to be inherited from a functional structure in a distant ancestor.

Mineralized Fossil

A type of fossil where bones are replaced with minerals over time.

Developmental Homology

Similar embryological structures shared by different species, such as pharyngeal pouches and post-anal tails in vertebrate embryos.