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  2. Red List Index - Wikipedia

    en.wikipedia.org/wiki/Red_List_Index

    The Red List Index (sampled approach) (SRLI) has been developed in order to determine the threat status and also trends of lesser-known and less charismatic species groups. It is a collaboration between IUCN members and is coordinated through the Institute of Zoology (IoZ), the research division of the Zoological Society of London (ZSL).

  3. Conservation status - Wikipedia

    en.wikipedia.org/wiki/Conservation_status

    The IUCN Red List of Threatened Species by the International Union for Conservation of Nature is the best known worldwide conservation status listing and ranking system. . Species are classified by the IUCN Red List into nine groups set through criteria such as rate of decline, population size, area of geographic distribution, and degree of population and distribution fragmenta

  4. Global Assessment Report on Biodiversity and Ecosystem ...

    en.wikipedia.org/wiki/Global_Assessment_Report...

    When estimating the effect of climate change on species' extinction risk, the report concluded that global warming of 2 °C (3.6 °F) over the preindustrial levels would threaten an estimated 5% of the Earth's species with extinction even in the absence of any other factors like land use change. If the warming reached 4.3 °C (7.7 °F), they ...

  5. Population viability analysis - Wikipedia

    en.wikipedia.org/wiki/Population_viability_analysis

    Population viability analysis (PVA) is a species-specific method of risk assessment frequently used in conservation biology.It is traditionally defined as the process that determines the probability that a population will go extinct within a given number of years.

  6. Diversification rates - Wikipedia

    en.wikipedia.org/wiki/Diversification_rates

    Diversification rates can be estimated time-series data on fossil occurrences. With perfect data, this would be an easy task; one could just count the number of speciation and extinction events in a given time interval, and then use these data to calculate per-lineage rates of speciation and extinction per unit time.

  7. Measurement of biodiversity - Wikipedia

    en.wikipedia.org/wiki/Measurement_of_biodiversity

    Species evenness is the relative number of individuals of each species in a given area. [1] Species richness [2] is the number of species present in a given area. Species diversity [3] is the relationship between species evenness and species richness. There are many ways to measure biodiversity within a given ecosystem.

  8. Quasi-extinction - Wikipedia

    en.wikipedia.org/wiki/Quasi-extinction

    The quasi-extinction threshold, or sometimes called the quasi-extinction risk is the population size below which a species is considered to be at extreme risk of quasi-extinction. [5] This threshold varies by species and is influenced by several factors, including reproductive rates, habitat requirements, and genetic diversity.

  9. Background extinction rate - Wikipedia

    en.wikipedia.org/wiki/Background_extinction_rate

    There are three different ways to calculate background extinction rate. [5] The first is simply the number of species that normally go extinct over a given period of time. For example, at the background rate one species of bird will go extinct every estimated 400 years. [6] Another way the extinction rate can be given is in million species ...