A new model developed by researchers at the University of California, Berkeley, sheds light on why some male greater sage grouse strut better than others. The model, published in the journal Current Biology, suggests that the size and shape of a male's air sac, as well as the timing of its inflation, all play a role in producing an impressive display.

The greater sage grouse is a large ground-dwelling bird found in the western United States. Males are known for their elaborate courtship displays, which involve inflating their air sacs and strutting around in front of females. The size of a male's air sac is thought to be an indicator of his health and fitness, and females are more likely to mate with males with larger air sacs.

However, the new model suggests that the shape of the air sac is also important. Males with more rounded air sacs produce louder and more resonant sounds, which are more likely to attract females. The timing of air sac inflation is also important. Males that inflate their air sacs in synchrony with their foot stomps produce a more impressive display.

The researchers believe that their model could be used to help manage greater sage grouse populations. By understanding the factors that contribute to a successful display, land managers could take steps to improve habitat conditions and increase the likelihood of successful reproduction.

"Our model provides new insights into the complex courtship behavior of greater sage grouse," said study lead author Dr. Robert Montgomerie. "This information could be used to help conserve this iconic species."