Birds that dive may be at greater risk of extinction

The animals could be becoming trapped in their environments by their own adaptations

photo of an African penguin standing on a rock and bowing its head

The African penguin (Spheniscus demersus) is one of many diving birds threatened with extinction.

Vicki Jauron, Babylon and Beyond Photography/Getty Images Plus

Birds that dive underwater — such as penguins, loons and grebes — may be more likely to go extinct than their nondiving kin, a new study finds.

Many water birds have evolved highly specialized bodies and behaviors that facilitate diving. Now, an analysis of the evolutionary history of more than 700 water bird species shows that once a bird group gains the ability to dive, the change is irreversible.