Extinction Rate per Lineage-Million-Year Calculator
Closedcohortconstantpercapita extinctionintensity−ln(Nsurvive/Nstart)/ΔMyr,not origination event/exposure renaming;no zero-survivorfiniteestimate. Actual independently identified specimens,matched units/taxon/cohort/source/edition/calibration and model applicability external;not individual identity,causation,diagnosis,absolute age certainty or validated forecast.
Description
A closed cohort's change in surviving lineages can be described by a constant per-capita extinction intensity.
A closed cohort's change in surviving lineages can be described by a constant per-capita extinction intensity.1
Origination and uncertain cohort membership require separate treatment.
When to use Extinction Rate per Lineage-Million-Year Calculator
Use this tool to apply the stated extinction rate per lineage-million-year calculator operation with an explicit input and unit basis.
How to use Extinction Rate per Lineage-Million-Year Calculator and how it works
- Establish the measurement basis and units described above.
- Enter actualLineageSurvivorsAtStart, actualLineageSurvivorsAtEnd, actualIntervalMyr and run the tool.
- Read result.perCapitaExtinctionIntensityPerMyr using the output meanings below.
- If input is rejected, correct the stated type, range, ordering or alignment issue and rerun; review successful results under the declared convention.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| actualLineageSurvivorsAtStart | Lineage survivors at start, on the basis specified in the algorithm. | number | required; finite; strictly positive; further conditions in the algorithm |
| actualLineageSurvivorsAtEnd | Lineage survivors at end, on the basis specified in the algorithm. | number | required; finite; strictly positive; further conditions in the algorithm |
| actualIntervalMyr | Interval myr, on the basis specified in the algorithm. | number | required; finite; strictly positive; further conditions in the algorithm |
Require positive start and end counts and duration in million years, with end no greater than start. Return log(start/end) divided by duration; zero survivors are outside this finite branch.
intensity per Myr = ln(start/end)/ΔMyr Apply the declared units, ordering and branch conditions.
| Output field | Meaning | Value type |
|---|---|---|
| result | Object containing the declared output fields. | object |
| result.perCapitaExtinctionIntensityPerMyr | Constant closed-cohort extinction intensity in inverse million years. | number |
{
"input": {
"actualLineageSurvivorsAtStart": 10,
"actualLineageSurvivorsAtEnd": 5,
"actualIntervalMyr": 2
},
"output": {
"result": {
"perCapitaExtinctionIntensityPerMyr": 0.34657359027997264
}
}
}Limitations and assumptions
The output applies the declared operation to the values you supply. Establish the measurement basis, units, coefficients and any caller-selected rules before interpreting it. The tool does not independently collect or verify observations or decide whether a model or reference applies.
Supply explicit required fields with the documented types and dense aligned arrays. Unknown fields, wrong types and nonfinite numbers are rejected. Branch-specific constraints are explained above. A successful false boolean, negative signed difference, empty slice or unresolved tie is distinct from an input error. Very large inputs or outputs may be rejected by shared resource limits.
Alternative or Complementary methods
For a related operation, use Rarefaction Species Count at Standardized N Calculator. Rarefaction estimates expected observed taxon richness in a smaller sample drawn without replacement from a finite counted inventory.
For a related operation, use Dominance Percent Top Taxon Calculator. Dominance percentage records the largest taxon's share of a counted assemblage.
References
Similar or alternative tools
- Rarefaction Species Count at Standardized N Calculator
Rarefaction estimates expected observed taxon richness in a smaller sample drawn without replacement from a finite counted inventory.
- Dominance Percent Top Taxon Calculator
Dominance percentage records the largest taxon's share of a counted assemblage.