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

Genetic Drift03:33

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.Life is not fair. A deer grazing contentedly in a field can have her meal cut tragically short by a bolt of lightning. If the doomed doe is one of only three in the population, 1/3 of the population’s gene pool is lost. Random events like this can...
What is Population Genetics?01:25

What is Population Genetics?

A population is composed of members of the same species that simultaneously live and interact in the same area. When individuals in a population breed, they pass down their genes to their offspring. Many of these genes are polymorphic, meaning that they occur in multiple variants. Such variations of a gene are referred to as alleles. The collective set of all the alleles within a population is known as the gene pool.While some alleles of a given gene might be observed commonly, other variants...
Genetics of Speciation02:16

Genetics of Speciation

Speciation is the evolutionary process resulting in the formation of new, distinct species—groups of reproductively isolated populations.The genetics of speciation involves the different traits or isolating mechanisms preventing gene exchange, leading to reproductive isolation. Reproductive isolation can be due to reproductive barriers that have effects either before or after the formation of a zygote. Pre-zygotic mechanisms prevent fertilization from occurring, and post-zygotic mechanisms...
Gene Flow02:39

Gene Flow

Gene flow is the transfer of genes among populations, resulting from either the dispersal of gametes or from the migration of individuals.
Conservation of Small Populations02:04

Conservation of Small Populations

Small population sizes put a species at extreme risk of extinction due to a lack of variation, and a consequent decrease in adaptability. This weakens the chances of survival under pressures such as climate change, competition from other species, or new diseases. Large populations are more likely to survive pressures such as these, as such populations are more likely to harbor individuals that have genetic variants that are adaptive under new stresses. Small populations are much less likely to...
Mutation, Gene Flow, and Genetic Drift01:09

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).Mechanisms of Genetic VariationThe original sources of genetic variation are mutations,...

You might also read

Related Articles

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

Sort by
Same author

Accounting for recombination rate variation improves inference of barrier loci and reveals the role of both natural and sexual selection in an incipient bird radiation.

Evolution; international journal of organic evolution·2026
Same author

Plain language summary of publication of the 96-week results from the PHOTON study: intravitreal aflibercept 8 mg for diabetic macular edema.

Therapeutic advances in ophthalmology·2026
Same author

Infographic: Study design for ELARA, an open-label, phase 3b trial of aflibercept 8 mg in previously treated patients with neovascular age-related macular degeneration or diabetic macular edema.

Eye (London, England)·2026
Same author

From Lineage Discovery to Conservation Prioritisation: An Integrative Genomic Framework Applied to a Model Damselfly System.

Molecular ecology·2026
Same author

Efficacy of Continuous Pegcetacoplan Treatment for Subfoveal Geographic Atrophy in Age-Related Macular Degeneration: 36-Month Results from OAKS, DERBY, and GALE Open-Label Extension.

Clinical ophthalmology (Auckland, N.Z.)·2026
Same author

Application of small molecule inhibitors to probe the mechanism underlying nanomaterial pulmonary inflammatory responses <i>in vitro</i>.

Nanotoxicology·2026

Related Experiment Video

Updated: Jul 8, 2026

Protocol for Assessing the Relative Effects of Environment and Genetics on Antler and Body Growth for a Long-lived Cervid
09:09

Protocol for Assessing the Relative Effects of Environment and Genetics on Antler and Body Growth for a Long-lived Cervid

Published on: August 8, 2017

Extensive population genetic structure in the giraffe.

David M Brown1, Rick A Brenneman, Klaus-Peter Koepfli

  • 1Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA, 90095, USA. giraffes@ucla.edu

BMC Biology
|December 25, 2007
PubMed
Summary
This summary is machine-generated.

Genetic analysis reveals at least six distinct giraffe lineages in Africa, challenging the single-species classification. These genetically isolated populations highlight the need for targeted conservation efforts for giraffe (Giraffa camelopardalis).

More Related Videos

A Noninvasive Hair Sampling Technique to Obtain High Quality DNA from Elusive Small Mammals
07:40

A Noninvasive Hair Sampling Technique to Obtain High Quality DNA from Elusive Small Mammals

Published on: March 13, 2011

Related Experiment Videos

Last Updated: Jul 8, 2026

Protocol for Assessing the Relative Effects of Environment and Genetics on Antler and Body Growth for a Long-lived Cervid
09:09

Protocol for Assessing the Relative Effects of Environment and Genetics on Antler and Body Growth for a Long-lived Cervid

Published on: August 8, 2017

A Noninvasive Hair Sampling Technique to Obtain High Quality DNA from Elusive Small Mammals
07:40

A Noninvasive Hair Sampling Technique to Obtain High Quality DNA from Elusive Small Mammals

Published on: March 13, 2011

Area of Science:

  • Evolutionary biology
  • Genetics
  • Mammalogy

Background:

  • Investigates evolutionary diversification in large, mobile mammals without apparent dispersal barriers.
  • Giraffes (Giraffa camelopardalis) are currently classified as one species with multiple subspecies.
  • Geographic variation in pelage patterns suggests reproductive isolation despite lack of extrinsic barriers.

Purpose of the Study:

  • To determine the genetic structure and evolutionary history of giraffe populations across Africa.
  • To assess the level of genetic differentiation among recognized giraffe subspecies.
  • To understand the mechanisms maintaining genetic diversity in giraffes.

Main Methods:

  • Analysis of mitochondrial DNA sequences.
  • Analysis of nuclear microsatellite loci.
  • Comparison of genetic data with geographic distribution and phenotypic variation.

Main Results:

  • Identification of at least six distinct, genealogically separate giraffe lineages in Africa.
  • Limited evidence of interbreeding between these lineages, suggesting reproductive isolation.
  • Discovery of at least 11 genetically distinct populations, with some maintained without contemporary barriers to gene flow.

Conclusions:

  • Extreme genetic subdivision in giraffes is unprecedented for a large vertebrate with high dispersal capabilities.
  • Findings imply that recognized subspecies represent long-term reproductively isolated units.
  • Results necessitate separate in situ and ex situ conservation and management strategies for distinct giraffe lineages and populations.