Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Evolution of New Traits in Microbes01:24

Evolution of New Traits in Microbes

129
Microorganisms evolve rapidly due to their large population sizes and short generation times, often exhibiting measurable changes within days under laboratory conditions. Natural selection acts on standing genetic variation, enabling the retention and amplification of beneficial traits that confer fitness advantages in changing environments.Adaptive Pigment Regulation in RhodobacterIn Rhodobacter, a genus of purple non-sulfur bacteria, light-harvesting pigments such as bacteriochlorophyll and...
129
Genetic Drift03:33

Genetic Drift

45.2K
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.
45.2K
Evolutionary Processes in Microbes01:26

Evolutionary Processes in Microbes

101
Microbial evolution occurs rapidly due to short generation times and a variety of genetic processes, including horizontal gene transfer, mutation, recombination, and genetic drift. These mechanisms collectively enable microbes to adapt swiftly to changing environments.Horizontal gene transfer (HGT) allows genes to move between different species and occurs through three main mechanisms: conjugation, transformation, and transduction. Conjugation involves direct cell-to-cell contact for DNA...
101
Types of Selection01:46

Types of Selection

46.4K
Natural selection influences the frequencies of particular alleles and phenotypes within populations in several different ways. Primarily, natural selection can be directional, stabilizing, or disruptive. Directional selection favors one extreme trait and shifts the population towards that phenotype while selecting against individuals displaying alternate traits. Stabilizing selection favors an intermediate trait with a narrow range of variation. Deviation from the optimal phenotype towards an...
46.4K
Population Growth00:57

Population Growth

29.5K
Population size is dynamic, increasing with birth rates and immigration, and decreasing with death rates and emigration. In ideal conditions with unlimited resources, populations can increase exponentially, which plots as a J-shaped growth rate curve of population size against time. This type of curve is characteristic of newly-introduced invasive species, or populations that have suffered catastrophic declines and are rebounding.
29.5K
Mutation, Gene Flow, and Genetic Drift01:09

Mutation, Gene Flow, and Genetic Drift

66.0K
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).
66.0K

You might also read

Related Articles

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

Sort by
Same author

Perioperative outcomes of robotic-assisted liver surgery: A comparison between patients with and without previous abdominal surgery.

Surgery open science·2026
Same author

CT-based vascular invasion in pancreatic ductal adenocarcinoma compared with intraoperative and histological findings.

Insights into imaging·2026
Same author

Macrophages in Intestinal Wound Healing: Dichotomous Effects and Therapeutic Opportunities.

International journal of molecular sciences·2026
Same author

Accurate <i>ab initio</i> gene prediction in eukaryotes with Tiberius in multiple clades.

bioRxiv : the preprint server for biology·2026
Same author

Pattern Formation Beyond Turing: Physical Principles of Mass-Conserving Reaction-Diffusion Systems.

Annual review of biophysics·2026
Same author

Longitudinal monitoring of circulating tumor cell dynamics for potential prediction of early recurrence and clinical outcomes after curative resection of hepatocellular carcinoma: a pilot study.

BMC cancer·2026

Related Experiment Video

Updated: Apr 5, 2026

Following the Dynamics of Structural Variants in Experimentally Evolved Populations
04:52

Following the Dynamics of Structural Variants in Experimentally Evolved Populations

Published on: February 3, 2023

1.4K

Non-Selective Evolution of Growing Populations.

Karl Wienand1, Matthias Lechner1, Felix Becker2

  • 1Arnold-Sommerfeld-Center for Theoretical Physics and Center for NanoScience, Physics Department, Ludwig-Maximilians-Universität, Munich, Germany.

Plos One
|August 15, 2015
PubMed
Summary

Exponential growth in small, variable populations halts genetic drift, leading to a stable, random trait composition instead of fixation. This finding is crucial for understanding evolution in dynamic populations.

More Related Videos

Daily Transfers, Archiving Populations, and Measuring Fitness in the Long-Term Evolution Experiment with Escherichia coli
15:00

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

Published on: August 18, 2023

4.6K
Procedure for Adaptive Laboratory Evolution of Microorganisms Using a Chemostat
06:03

Procedure for Adaptive Laboratory Evolution of Microorganisms Using a Chemostat

Published on: September 20, 2016

15.5K

Related Experiment Videos

Last Updated: Apr 5, 2026

Following the Dynamics of Structural Variants in Experimentally Evolved Populations
04:52

Following the Dynamics of Structural Variants in Experimentally Evolved Populations

Published on: February 3, 2023

1.4K
Daily Transfers, Archiving Populations, and Measuring Fitness in the Long-Term Evolution Experiment with Escherichia coli
15:00

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

Published on: August 18, 2023

4.6K
Procedure for Adaptive Laboratory Evolution of Microorganisms Using a Chemostat
06:03

Procedure for Adaptive Laboratory Evolution of Microorganisms Using a Chemostat

Published on: September 20, 2016

15.5K

Area of Science:

  • Evolutionary biology
  • Population genetics
  • Microbial evolution

Background:

  • Non-selective evolutionary forces like genetic drift are well-studied in constant-sized populations.
  • Growing populations with small sizes and diverse traits, such as after a bottleneck, present unique evolutionary dynamics.
  • Previous models primarily focused on trait fixation in constant populations.

Purpose of the Study:

  • To investigate non-selective evolution in small, growing populations with varying trait compositions.
  • To determine if traits fixate or if populations reach a stable state under these conditions.
  • To explore the influence of initial conditions on the final population composition.

Main Methods:

  • Combined theoretical modeling using the Pólya urn model with experimental evolution.
  • Utilized multiple mixed subpopulations of Pseudomonas putida strains under non-selective growth.
  • Analyzed population dynamics and trait composition changes over time.

Main Results:

  • Growing populations do not lead to trait fixation but stabilize at a random composition.
  • The distribution of trait compositions reaches a steady state, influenced by initial conditions.
  • Experimental results align with theoretical predictions from the Pólya urn model.

Conclusions:

  • Exponential growth effectively counteracts genetic drift in small, variable populations.
  • Population growth plays a critical role in maintaining genetic variability.
  • Findings are significant for life-cycle models involving fluctuating population sizes.