Endemism.org publishes biological data and reference pages about endemic species, native ranges, taxonomy, and geographic patterns of endemism. Published claims are checked against sources that can support the exact taxonomic rank, geographic scope, and type of data being presented.
Evidence standards
Endemic status is assigned only when reliable evidence supports restriction of a species’ natural native range to the geographic area described on the page. A species is not treated as endemic because most observations happen to come from one country, island, state, or region.
Sources are selected according to the biological question being answered. Taxonomic status, native distribution, conservation assessment, and national biodiversity counts may require different authorities. One source is not assumed to be suitable for every type of claim.
Occurrence alone does not establish endemism. Observation records can document presence, but absence of records elsewhere is not evidence that a species has no native range outside the area being studied.
Source priority
Preference is given to sources with direct responsibility for taxonomy, biodiversity inventories, species assessment, or geographic distribution. Depending on the taxonomic group and subject, these may include specialist databases, government biodiversity agencies, botanical authorities, conservation databases, museums, universities, and peer-reviewed taxonomic or biogeographic research.
Original datasets and primary biological sources are preferred when they are available. Secondary articles may help locate a dataset, but they are not used as substitutes when the underlying source can be checked directly.
Source authority depends on the claim. A taxonomic backbone may be suitable for an accepted scientific name while a national wildlife agency or specialist species account may provide stronger evidence for a restricted native range.
Native-range rules
Endemism is evaluated from natural native distribution. Introduced, naturalized, cultivated, captive, planted, or conservation-translocated populations are not treated as extensions of the original native range.
When a species naturally occurs within a smaller geographic unit, the narrowest well-supported range is preferred. A species confined to one island, spring system, mountain range, cave, watershed, or aquifer can also fall within a broader national endemic scope, but the more precise range is retained where the evidence supports it.
Subnational figures are not presented as national totals. Counts from separate regions are not added together unless the source methodology supports the resulting total and the underlying records use compatible definitions.
Taxonomic control
Current accepted species names are preferred. Synonyms are not counted as separate species, and recent taxonomic splits or mergers are considered when they affect the identity or endemic status of a record.
Species are kept separate from subspecies, varieties, forms, populations, and other infraspecific units. A dataset reporting taxa is not rewritten as a species count unless the source itself defines those records at species rank.
Scientific names are checked for basic taxonomic consistency, including genus capitalization, specific-epithet formatting, and placement in the correct broad biological group. Common names are omitted when they cannot be supported reliably.
Quantitative data
National and regional statistics are retained within the definitions used by their source datasets. Counts with different geographic scopes, taxonomic ranks, update cycles, extinction treatments, or coverage are not combined into synthetic totals.
When a compatible dataset provides both a numerator and denominator, a derived percentage may be calculated from those values. The calculation must preserve the source scope and should not introduce a level of numerical precision that the underlying data do not support.
Approximate values remain approximate. Phrases such as “more than,” “about,” or “approximately” are not converted into exact figures.
Species checklist verification
Species checklists are built from records that can be supported at species rank. Each entry is evaluated for accepted name, broad taxonomic group, natural range, and the geographic basis for endemic status.
Checklist length is determined by the available evidence rather than a fixed number of examples. When a reliable source supports additional species identities, research continues beyond a short representative list. When identities cannot be verified at the required level, uncertain records are left out rather than inferred.
Duplicate accepted species are removed even when the same species appears in several sources or geographic sections. Synonyms and historical combinations do not create additional checklist records.
Extinct and historical records
Extinct species may be included when their historical native range and taxonomic status are adequately documented. Extinction is distinguished from local extirpation, and historical endemic status is based on the documented natural range rather than present-day occurrence alone.
Extant and extinct records are not silently merged when that distinction affects interpretation of a total or checklist.
Dataset versions
Where a source is issued in versions or periodic releases, newer compatible data are preferred. A newer version does not automatically replace an older figure when definitions, geographic scope, or taxonomic treatment have changed.
Older values may remain relevant when they describe a historical benchmark or when a newer release does not provide the same metric. Such figures are kept within their original context rather than presented as current equivalents.
Citation policy
Factual and quantitative claims are connected to source references through the citation system used across Endemism.org. The same source retains the same reference number within a page, and source details are listed separately from the article text.
National data tables use compact source references beside the values they support. Source names, publication titles, and direct external URLs are not inserted into table cells where they would make the data harder to read.
Corrections
Published pages may be revised when accepted taxonomy changes, a distribution record is corrected, a newer authoritative dataset becomes available, or an error is identified in a count, range, citation, or species record.
Corrections are based on the underlying evidence. A record is not changed solely to make different datasets agree with one another, and conflicting sources are not resolved by choosing the larger or more convenient number.
Editorial boundaries
Endemism.org does not create unsupported species totals, invent common names, infer endemic status from incomplete occurrence maps, or convert regional datasets into national figures without evidence that such a calculation is valid.
Where the available information is incomplete, the page retains that limitation. Missing data are preferable to a precise-looking value that cannot be defended from the source material.