Full circumpolar migration ensures evolutionary unity in the Emperor penguin.

Area of Science:

• Ecology
• Genomics
• Conservation Biology

Background:

• Demographic models are vital for predicting species' responses to environmental change.
• Current models often rely on single-population data, assuming stationarity and independence, which may be inaccurate for remote species.
• The Emperor penguin (Aptenodytes forsteri) is a key Antarctic species facing potential continent-wide risks.

Purpose of the Study:

• To investigate the demographic structure of the Emperor penguin across the Antarctic continent.
• To determine if local populations represent distinct demographic units or if a global population structure exists.
• To improve the accuracy of extinction risk assessments for this species.

Main Methods:

• Utilized genome-wide data from Emperor penguin populations across the entire Antarctic continent.
• Analyzed genetic data to infer population structure and demographic history.
• Incorporated dispersal rates into extinction risk modeling.

Main Results:

• Revealed that the Emperor penguin functions as a single, interconnected global population.
• Demonstrated a shared demographic history since the late Quaternary, refuting the concept of isolated local units.
• Showcased that colony size reflects local events, while species-wide response to climate change follows a unified evolutionary path.

Conclusions:

• The Emperor penguin's demographic unit is continental, not local, necessitating a global approach to conservation.
• Accurate extinction risk assessments require integrating dispersal rates and recognizing the species' shared evolutionary trajectory.
• Understanding this global demography is critical for predicting the impact of environmental change on Emperor penguins.