Occurrence data and range maps in endemicity analysis: Data choice matters.

Area of Science:

• Biogeography
• Ecology
• Conservation Biology

Background:

• Biogeographic analyses rely heavily on species distribution data quality.
• Different data types, like occurrence records and range maps, can yield varying results.
• Understanding these differences is vital for accurate biodiversity assessments.

Purpose of the Study:

• To compare point-based occurrence records and polygonal range maps for 160 Liolaemus lizard species.
• To assess the influence of data type on identifying areas of endemism across spatial scales.
• To determine the most reliable data source for robust biogeographic analyses.

Main Methods:

• Endemicity analysis was performed on occurrence records and range maps.
• Data were compared across three distinct spatial scales.
• The study focused on the lizard genus Liolaemus, encompassing 160 species.

Main Results:

• Range maps tend to overestimate species distributions, creating broad, less accurate endemic areas.
• Occurrence data identify fewer, more localized, and compositionally distinct areas of endemism.
• Occurrence data are more sensitive to spatial scale, revealing fine-grained patterns, especially in heterogeneous environments.

Conclusions:

• Occurrence data provide a more ecologically meaningful representation of endemism than range maps.
• Data choice critically influences the detection of endemism and conservation planning outcomes.
• Researchers must select data sources carefully based on species traits and study scale for reliable analyses.