effective population size
Let an agent define effective population size, explain why it differs from census size and how it is estimated, relay conservation rules of thumb with attribution, and separate it from census counts and from minimum viable population.
Bundle → Layer → Finding → Questions Filled
4 bundles · 8 layers · 8 findings · 16 questions
Concept What effective size is.
Definition
Definition.
Definition
Definition.
- What is effective population size, and why does it differ from census size? definition
- Is the question about effective size, census size or minimum viable population? boundary
Variants
Variants.
Variants
Variants.
- How do variance, inbreeding and other effective sizes differ? definition
- Which entry fits genetic drift? action
Estimate Estimation.
Demographic
Demographic methods.
Demographic
Demographic.
- How is effective size estimated from sex ratio, family size and fluctuations? measurement
- Which formulas apply? provenance
Genetic
Genetic methods.
Genetic
Genetic.
- How is it estimated from genetic markers, and with what uncertainty? measurement
- Which software and references are standard? provenance
Apply Conservation use.
Thresholds
Rules of thumb.
Thresholds
Thresholds.
- What thresholds such as the 50/500 rule are used, and how are they debated, with attribution? provenance
- Is the presentation neutral on the debate? boundary
Management
Management.
Management
Management.
- How do managers raise effective size in captive and wild populations? provenance
- Which entry fits conservation genetics? action
Learn History and teaching.
History
History.
History
History.
- How did Wright and later geneticists develop the concept? provenance
- Which entry fits population genetics? action
Teach
Teaching.
Teach
Teaching.
- How is effective size taught, and which misconceptions arise? provenance
- Which references are standard? provenance
Classifiers Filled
- Family
- Thing Registry
- Category
- Cross-cutting context
- Entry kind
- thing
- Plane
- XCT
- Domain
- XCT.QTY
What it is Filled
In population genetics, the size of an idealised population that would lose genetic diversity through drift at the same rate as the real population; usually much smaller than the census size because of unequal sex ratios, variation in family size and fluctuations over time, and used in conservation to judge the genetic risk to small populations.
Why it exists Filled
Let an agent define effective population size, explain why it differs from census size and how it is estimated, relay conservation rules of thumb with attribution, and separate it from census counts and from minimum viable population.
Distinguishing features Filled
- Genetic rather than demographic measure
- Depends on sex ratio, family size variance and fluctuation
- Variance and inbreeding effective sizes as variants
- Estimated from pedigrees or genetic markers
What robots and AI may and may not do Filled
Must not
- Use census counts in place of effective size when judging genetic risk.
- Present thresholds such as the 50 and 500 rules of thumb as fixed laws.
- Report estimates from small or unrepresentative samples without saying so.
- Misstate a species' genetic status to support or oppose a conservation decision.
Only with a human decision
- Using an estimate to decide on listing, culling or translocating a population.
May
- Explain how effective population size differs from census size.
- Report published estimates with their method, sample and uncertainty.
Moral aspects Filled
- Conservation decisions on whole species can rest on this number.
- Small effective size means lost diversity that cannot be recovered.
Who is affected
- Threatened species and populations
- Conservation managers
- Breeders of domestic animals
Owners Filled
Steward
Nobody owns the concept; researchers answer for each published estimate.
Links to other meta-models Filled
parent
- Q1613416 - registry parent class
related
- population size - a genetic measure of size
- genetic drift - the rate of drift
- conservation genetics - risk assessment
- census population size - the head count
What else AI and robots need to interact with it Filled
Identity and identifiers required Filled
- Vercy registry: vr.tr.effective-population-size
- Wikidata: Q1295959 (https://www.wikidata.org/wiki/Q1295959)
Direct properties not applicable Not applicable
- typical ratio to census size: about 0.1-0.5 ratio - varies widely by species
- conservation rule of thumb: 50 and 500 individuals - the 50/500 rule, debated
Plane XCT: no invented physical properties.
Recognition optional Filled
- Idealised size matching the drift rate
- Smaller than the census population in almost all cases
- Census size counts individuals; minimum viable population is a different threshold
- Not visible; a number derived from demographic or genetic data.
Capabilities and actions required Filled
- explain the concept and its variants
- explain why it is smaller than census size
- relay estimation methods
- relay conservation thresholds with attribution
Hazards and failure modes required Filled
- Using census size in place of effective size
- Applying rules of thumb as fixed laws
- Poor estimates from small samples
Standards and interfaces required Filled
- IUCN Red List criteria that use population size
- Conservation genetics guidelines
Context of use required Filled
- Judging the rate of genetic drift and inbreeding in a population.
- variance effective size
- inbreeding effective size
- eigenvalue effective size
- contemporary and historical estimates
- effective size in conservation assessments
Sources Filled
- Wikidata item Q1295959: effective population size - identity and sense of the item
- Wikipedia: Effective population size - general description of the item
Open questions
- Should the variants be separate entries?
- How should estimation software be linked?
- How should the 50/500 debate be recorded?
Machine files
Provenance
thing registry research (pass 2) · unreviewed
Built from: models/things/publications/thing-q1295959/spec.json