Birds use their beaks as air conditioners

Birds’ beaks have evolved in many ways for many different situations. They can dig deep for food, some can poke deep into flowers. These different uses vary quite vastly around the world. In a new study published in The Auk: Ornithological Advances, the journal of The American Ornithologists’ Union shows that the beak’s internal structure is complex, designed to help cool birds in warm climates.

Raymond Danner of the University of North Carolina Wilmington and his colleagues from Cornell University and the National Museum of Natural History gathered specimens from two Song Sparrow subspecies; One from an area with little moisture and a warmer climate and the other found further inland where it is cooler. Danner and his colleagues examined the nasal conchae of the bird bills.

According to allaboutbirds.org, “Nasal conchae are complex structures inside bird bills that moderate the temperature of air being inhaled and reclaim water from air being exhaled.”

Danner and his group found that the conchae structure had a larger surface area and sat farther out within the beak in Song Sparrows found in warmer climates. The structures in Song Sparrows found in cooler climates were smaller and more condensed in general. The larger surface area in warm climated Sparrows hypothetically increased their beaks’ ability to cool air and recapture water.

The birds used in this study were preserved in ethanol and iodine. They were then CT scanned and were shown more clearly as the chemicals concentrated the soft tissues. This technique is quite new to Ornithologists, scientists who devote their studies to birds, and, therefore, open up a new world of understanding for these scientists.

Jason Bourke, a researcher from the North Carolina Museum of Natural Sciences not involved in the study says, “Thanks to the use of innovative techniques like diceCT, we are now able to really appreciate just how complicated bird noses can be.”