Muskoxen, Wrangel Island, Russia
Photograph by Sergey Gorshkov
This Month in Photo of the Day: Animal PicturesTwo bull muskoxen size each other up. In September, with mating season under way, bulls engage in frequent head-butting confrontations to establish dominance.
See more pictures from the May 2013 feature story “Russian Refuge.”
(via: National Geo)
one of my favorite animals