Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Genetic Drift

Genetic Drift

Natural selection—probably the most well-known evolutionary mechanism—increases the prevalence of traits that enhance survival and reproduction. However, evolution does not merely propagate favorable traits, nor does it always benefit populations.

The Evidence for Evolution

The Evidence for Evolution

Genetic variations accumulating within populations over generations give rise to biological evolution. Evolutionary changes can result in the formation of novel varieties and entire new species. These changes are responsible for the diverse forms of life inhabiting the planet. The evidence for evolution suggests that all living organisms descended from common ancestors.

What is Evolutionary History?

What is Evolutionary History?

Scientists record evolutionary history by analyzing fossil, morphological, and genetic data. The fossil record documents the history of life on Earth and provides evidence for evolution. However, both fossil and living organisms offer evidence that outlines Earth’s evolutionary history.

Mutation, Gene Flow, and Genetic Drift

Mutation, Gene Flow, and Genetic Drift

In a population that is not at Hardy-Weinberg equilibrium, the frequency of alleles changes over time. Therefore, any deviations from the five conditions of Hardy-Weinberg equilibrium can alter the genetic variation of a given population. Conditions that change the genetic variability of a population include mutations, natural selection, non-random mating, gene flow, and genetic drift (small population size).

Speciation Rates

Speciation Rates

Gene Flow

Gene Flow

Gene flow is the transfer of genes among populations, resulting from either the dispersal of gametes or from the migration of individuals.

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

The chemistry of habitable oceans in the Solar system.

Nature communications·2026

Same author

Predictions From Evolutionary Theory for Urban Environments.

Evolutionary applications·2026

Same author

Evolving nature-based solutions for urban resilience.

Science (New York, N.Y.)·2026

Same author

A Multi-City Assessment of Genomic Evolution in the Native Wildflower <i>Impatiens capensis</i>.

Evolutionary applications·2026

Same author

Repeated snowball-hothouse cycles within the Neoproterozoic Sturtian glaciation.

Proceedings of the National Academy of Sciences of the United States of America·2026

Same author

Abiotic CO<sub>2</sub> reduction promoted by carbonate and phyllosilicate minerals on the primitive seafloor.

Nature communications·2026

Search research articles

Related Experiment Video

Updated: Mar 2, 2026

Author Spotlight: Understanding Microbe Adaptation Using Innovative Techniques for Exploring Thermophilic Evolution

Author Spotlight: Understanding Microbe Adaptation Using Innovative Techniques for Exploring Thermophilic Evolution

Published on: June 14, 2024

Evolution caused by extreme events.

Peter R Grant¹, B Rosemary Grant², Raymond B Huey³

¹Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA prgrant@princeton.edu.

Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences

|May 10, 2017

Summary

Extreme environmental events, like heat waves or floods, can drive rapid evolutionary change. Researchers should prepare for these evolutionary responses during long-term ecological studies.

Keywords:

adaptation extinction long-term studies physiology

More Related Videos

Daily Transfers, Archiving Populations, and Measuring Fitness in the Long-Term Evolution Experiment with Escherichia coli

Daily Transfers, Archiving Populations, and Measuring Fitness in the Long-Term Evolution Experiment with Escherichia coli

Published on: August 18, 2023

Following the Dynamics of Structural Variants in Experimentally Evolved Populations

Following the Dynamics of Structural Variants in Experimentally Evolved Populations

Published on: February 3, 2023

Related Experiment Videos

Last Updated: Mar 2, 2026

Author Spotlight: Understanding Microbe Adaptation Using Innovative Techniques for Exploring Thermophilic Evolution

Author Spotlight: Understanding Microbe Adaptation Using Innovative Techniques for Exploring Thermophilic Evolution

Published on: June 14, 2024

Daily Transfers, Archiving Populations, and Measuring Fitness in the Long-Term Evolution Experiment with Escherichia coli

Daily Transfers, Archiving Populations, and Measuring Fitness in the Long-Term Evolution Experiment with Escherichia coli

Published on: August 18, 2023

Following the Dynamics of Structural Variants in Experimentally Evolved Populations

Following the Dynamics of Structural Variants in Experimentally Evolved Populations

Published on: February 3, 2023

Area of Science:

Evolutionary Biology
Ecology
Environmental Science

Background:

Extreme environmental events, such as mass extinctions, have historically driven significant evolutionary diversification.
Contemporary evolution is often perceived as gradual, but extreme events impose strong selection pressures, acting as analogues to past dramatic changes.
The evolutionary consequences of contemporary extreme events are less studied than their ecological impacts.

Purpose of the Study:

To review case studies on contemporary evolution in response to extreme environmental perturbations.
To explore the evolutionary impacts of both episodic (pulse) and prolonged (press) extreme events.
To highlight the importance of considering evolutionary responses to rare environmental events in ecological research.

Main Methods:

Review of existing literature and case studies focusing on contemporary evolution.
Analysis of evolutionary responses to different types of extreme environmental perturbations (pulse vs. press).
Synthesis of findings to understand conditions favoring evolutionary change.

Main Results:

Extreme events, analogous to past mass extinctions, can trigger contemporary evolution.
Evolution is most likely to occur when extreme events significantly alter community composition.
Both pulse and press perturbations can lead to evolutionary changes.

Conclusions:

Extreme environmental events are significant drivers of evolutionary change, even in contemporary times.
Investigating evolutionary responses to rare events is crucial for understanding ecological dynamics.
Long-term field studies should be designed to anticipate and study evolutionary changes resulting from extreme events.