Related Experiment Video
Updated: Jun 4, 2026
04:10
Visually Sexing Loggerhead Shrike (Lanius Ludovicianus) Using Plumage Coloration and Pattern
Published on: March 8, 2020
Does reduced heterozygosity influence dispersal? A test using spatially structured populations in an alpine ungulate
Aaron B A Shafer1, Jocelyn Poissant, Steeve D Côté
1Department of Biological Sciences CW 405, Biological Sciences Building, University of Alberta, Edmonton, Alberta, Canada. shafer@ualberta.ca
Biology Letters
|January 29, 2011
Summary
Animals that disperse may be less genetically diverse. This study on mountain goats found dispersed individuals had lower observed heterozygosity (H(O)) than residents, suggesting a link between genetic diversity and dispersal behavior.
Area of Science:
- Ecology
- Evolutionary Biology
- Genetics
Background:
- Animal dispersal is crucial for population dynamics but poorly understood.
- Evolutionary theories suggest less successful individuals disperse ('fitness-associated dispersal').
- Higher heterozygosity is often linked to increased individual fitness.
Purpose of the Study:
- To investigate the relationship between heterozygosity and dispersal in mountain goats (Oreamnos americanus).
- To test the 'fitness-associated dispersal' hypothesis by comparing heterozygosity in dispersers versus residents.
Main Methods:
- Utilized genetic data and population monitoring.
- Classified individuals as dispersers, residents, or admixed using cross-assignment.
- Compared observed heterozygosity (H(O)) among these groups.
Main Results:
- Dispersers exhibited the lowest mean H(O), followed by residents, then admixed individuals.
- Dispersed individuals showed 6.3% less H(O) compared to their subpopulation of origin.
- In a long-term study, immigrants had lower H(O), while emigrants showed the opposite pattern, potentially due to density dependence.
Conclusions:
- Provides the first empirical evidence linking heterozygosity to animal dispersal.
- Supports the 'fitness-associated dispersal' hypothesis in mountain goats.
- Suggests genetic diversity may influence an individual's decision to disperse.
Related Concept Videos
02:04Conservation 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...
02:39Gene Flow
Gene flow is the transfer of genes among populations, resulting from either the dispersal of gametes or from the migration of individuals.
01:09Mutation, 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,...
00:54Distribution and Dispersion
Ecology is the study of how organisms interact with their environment and with one another. An important aspect of ecology is understanding where species are found and how individuals are distributed within those areas. The geographic range of a species refers to the total area where its members are located, while dispersion describes the pattern of spacing of individuals within that range.Geographic Range and Dispersion PatternsWithin a species’ geographic range, individuals may be distributed...
02:16Genetics 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...
02:29Hybrid Zones
Hybrid zones are narrow regions where two closely related species interact, mate, and produce hybrids. Relative to either parent species, hybrids may possess distinct phenotypic or genetic differences that impact their survival and reproductive success. The genetic variances introduced by hybridization influence species diversity and speciation processes within the hybrid zone.Gene flow and natural selection are evolutionary mechanisms that shape the outcome of a hybrid zone. Gene flow...