Interdisciplinary Study Reveals How Birds Emit Heat Into Space Through Specialized Infrared Reflectance in Feathers

Groundbreaking research from UCLA and NHM reveals that bird feathers are evolved to emit mid-infrared radiation into space to manage rising global temperatures.

By: AXL Media

Published: Mar 18, 2026, 9:39 AM EDT

Source: Information for this report was sourced from Natural History Museum of Los Angeles County

Uncovering the Invisible Spectrum of Avian Thermal Regulation

In a first of its kind study published in Integrative Organismal Biology, researchers have moved beyond the visible colors of birds to explore how they manage heat through the mid-infrared spectrum. While biologists have long understood Gloger’s rule, which relates bird coloration to climate and humidity, the invisible wavelengths of heat emittance remained a mystery until now. By combining the expertise of material engineers from UCLA with museum biologists, the team was able to measure how feathers interact with light, heat, and color. This interdisciplinary approach revealed that bird feathers are not just for flight or display but serve as sophisticated thermal structures capable of managing intense heat loads in a warming world.

Engineering Meets Biology to Map Thermal Adaptive Strategies

The research utilized advanced spectrometers, typically used in thermal engineering, to analyze museum specimens from geographically diverse regions. Thomas Lee, a co-lead author and PhD candidate at UCLA, noted that nature contains highly optimized, multifunctional adaptations that engineers seek to replicate for passive cooling technologies. By providing specialized instruments to the biological community, the engineering team allowed for the measurement of near-infrared absorption and mid-infrared emittance. This synergy between departments has opened a new door for bioinspired design, potentially leading to the development of synthetic materials that mimic the way birds shed heat into their environment.

The Role of Habitat in Shaping Infrared Emittance Profiles

The study examined five North American bird species: the great horned owl, Northern bobwhite, Stellar’s jay, song sparrow, and common raven. Among these, the Northern bobwhite showed the most significant variation in heat emittance across different populations. Dr. Allison Shultz, Curator of Ornithology at the Natural History Museum of Los Angeles County, explained that birds living in open prairies and grasslands face higher selective pressure to emit heat. Because space is significantly colder than Earth, birds without overhead cover can shed mid-infrared radiation directly into the vacuum of space. This suggests that the physical environment, specifically exposure to the open sky, is a primary driver in the evolution of feather reflectance...