Estimating how many undescribed species have gone extinct

Area of Science:

• Biodiversity research
• Conservation biology
• Taxonomy

Background:

• Modern species extinctions and scientific descriptions began concurrently in the eighteenth century.
• A significant number of species likely went extinct before being scientifically described.
• Estimating the loss of undescribed species has been a persistent challenge in conservation science.

Purpose of the Study:

• To quantify the extinction of undescribed species across various taxonomic groups and regions.
• To evaluate the impact of neglecting undescribed species extinctions on total species richness projections.
• To assess the accuracy of extinction rate models under varying species description and extinction probabilities.

Main Methods:

• Applied known extinction rates from recorded species losses to models of undiscovered species.
• Utilized exponential decay models for the proportion of remaining undiscovered species.
• Tested model sensitivity using simulated data with non-constant extinction and description probabilities.

Main Results:

• Actual species losses are significantly underestimated when only recorded extinctions are considered.
• The proportion of undiscovered extinct species ranged from 15% to 59% of total extinctions.
• Recent extinction events may be up to twice as large as previously recorded.

Conclusions:

• The extinction of undescribed species is a substantial component of global biodiversity loss.
• Current estimates of species extinctions require upward revision to account for undescribed losses.
• Conservation strategies must consider the potential loss of species yet to be discovered.