Evolution: Fact vs Theory Review

Vocabulary flashcards encompassing key terms and concepts related to evolution.

Fact

Observations about the world around us.

Hypothesis

A proposed explanation for a phenomenon made as a starting point for further investigations.

Theory

A well-tested and confirmed explanation of a phenomenon through observation and experimentation.

Law

A detailed description, usually using math, of how something happens.

Natural Selection

The mechanism for evolution where individuals compete for resources, and those suited to the environment survive and reproduce.

Gene Pool

The total set of genetic information within a population.

Survival of the Fittest

The concept that individuals who are better adapted to their environment are more likely to survive and reproduce.

Directional Selection

A mode of natural selection where environmental changes cause one phenotype to replace another.

Diversity Selection (Disruptive Selection)

Natural selection where individuals at the extremes have higher fitness than those in the middle, potentially leading to two different populations.

Stabilizing Selection

Natural selection that favors average individuals within a population.

Fossil Record

A history of life on Earth documented by comparing fossils from different rock layers.

Adaptive Radiation

The evolution of many diversely adapted species from a common ancestor, usually after colonization of diverse environments.

Homologous Structures

Structures that have different mature forms but develop from the same embryonic tissue, indicating common ancestry.

Analogous Structures

Structures that have similar functions and appearances but different anatomical structures, indicating no common ancestry.

Vestigial Organs

Reduced size organs that are traces of homologous organs in other species, with no current function.

Microevolution

Evolution occurring within a population over a short time scale.

Macroevolution

Large-scale evolutionary changes that lead to the emergence of new species.

Speciation

The process that produces a new species through gene flow interruption and genetic divergence.

Gradualism

The theory that organisms descend from a common ancestor slowly over a long period.

Punctuated Equilibrium

The theory that new species appear suddenly after long periods of little change.

Cladograms

Branching diagrams that show the relationship between different species based on shared characteristics.