Photograph by Alexander Badyaev

A pair of gray foxes (Urocyon cinereoargenteus) is at home in a tall ironwood tree, high above the Sonoran Desert floor. The species first evolved more than 7 million years ago in the lush tropical forests that once covered what is today’s American Southwest. Since that time, this anatomically distinct fox has accumulated an impressive array of un-fox-like adaptations for life in the canopy, including primate-like flexible wrists and cat-like paws with long, curved claws that allow it to grip tree branches. This arsenal allows this uniquely arboreal fox species to sneak up on birds roosting near the tips of branches and to drag heavy objects—here, the skeleton of a fawn—into the canopy. Fox pairs use the skeletons as pungent scent posts to mark their territories. Particularly after rain, the smell of these “skeleton trees” can be quite powerful and can carry great distances.

Tucson, Arizona
Hi, I’m Dave, the executive director of bioGraphic. (And that’s my dog, Finn.) Thanks for taking the time to read this story.
Stories like this simply don’t get produced without financial support from readers like you. bioGraphic is an independent non-profit—we’re not backed by a private company or owned by a billionaire. One-quarter of our budget comes directly from reader donations.
bioGraphic publishes environmental reporting that you can’t find anywhere else: deeply researched, trustworthy stories that are also beautiful and captivating to read. Right now, we need your help to raise $30,000 by October 2. Every dollar will go directly to more crucial reporting projects.
Around the world, governments are slashing funding for conservation and scientific research, placing even more ecosystems and wildlife at risk. At bioGraphic, we’re steadfastly shining a light on the threats to our planet’s incredible biodiversity. And we’re showcasing the hard work of people bravely taking action to protect at-risk species.
bioGraphic offers an antidote to apathy and doom-and-gloom news by revealing the wonders of the natural world and focusing on real solutions to big problems. When you finish a bioGraphic story, we want to leave you feeling informed, delighted, and inspired.
We don’t run ads or hide our stories behind a paywall. The readers who generously support bioGraphic allow our work to remain free for everyone.
We reached our goal, but there’s time left. Will you help us smash our original goal and reach a new goal of $30,000 by October 2?