Summary
Variation of alleles within a species that enables adaptation and resilience.
In depth
Measured by heterozygosity, allelic richness and nucleotide diversity. Loss reduces ability to adapt and increases inbreeding. Crop genebanks maintain diversity.
Low diversity reduces adaptive potential and increases inbreeding depression. Conservation aims to keep diversity.
Remember: loss of diversity is often invisible until crisis.
Genetic diversity is the variation in alleles and genotypes within and among populations of a species. It is the raw material for evolution and lets populations adapt to disease, climate and new environments.
It is generated by mutation, recombination and gene flow, and lost by drift, bottlenecks, inbreeding and selection. Small populations lose diversity faster, which causes inbreeding depression (lower survival and fertility) and reduced adaptability. Measures include heterozygosity, allelic richness and nucleotide diversity. The cheetah has very low variation after past bottlenecks. Crop monocultures such as the Irish potato lacked diversity, with disastrous results in the potato famine.
Key idea: conserving populations, not just species, preserves genetic diversity.
Frequently asked questions
What is Genetic Diversity?
Variation of alleles within a species that enables adaptation and resilience.
Which area of biology covers Genetic Diversity, and how advanced is it?
Genetic Diversity is one of the 52 topics in Taxonomy & Biodiversity. It is rated Intermediate, so it suits learners who already know the core vocabulary. Related topics in this area include Genetic Rescue, Conservation Biology, Conservation Genomics.
Can you give an example of Genetic Diversity?
Banana varieties are clones, making them vulnerable to Panama disease.
What should I learn before Genetic Diversity?
Work through the Beginner topics in Taxonomy & Biodiversity first, such as Taxonomy, Binomial Nomenclature, Taxonomic Hierarchy, then return to Genetic Diversity. Intermediate topics assume the Beginner vocabulary.
What topics are related to Genetic Diversity?
The closest topics to Genetic Diversity are Genetic Rescue, Conservation Biology, Conservation Genomics, Minimum Viable Population. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Genetic Diversity?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Genetic Diversity. To practise the whole of Taxonomy & Biodiversity, use the Taxonomy & Biodiversity quiz.
How is Genetic Diversity different from Genetic Rescue?
Genetic Diversity: Variation of alleles within a species that enables adaptation and resilience. Genetic Rescue: Introducing individuals from other populations to reverse inbreeding depression, as with Florida panthers. Read both side by side and note what each one explains.
How should I study Genetic Diversity step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Genetic Rescue and explain the difference aloud. Finally, take the Taxonomy & Biodiversity quiz and come back to this page for any question you miss.