Every fall, leading into winter, the sun sets further and further into the south. The days get shorter and the sun’s rays diminish in duration and intensity. This is when D3—”the sunshine vitamin”—blood levels drop in sun-exposed mammals.
That imperceptible signal results in profound behavioral changes that are easily observed in foxes, bears, and many other land roaming creatures: their activity slows while their foraging increases.
Copy and paste this URL into your WordPress site to embed
Copy and paste this code into your site to embed