Did you know?

Reindeer are the only deer species where both males and females grow antlers. Though the males shed their antlers in late autumn after mating season, the females retain theirs throughout the winter pregnancy to defend scarce food patches. It is likely then, that Rudolph was in fact a female rather than a male!

Sketch by Victor Santiago
Fact contributed by Josie Hubbard and Victor Santiago

For more information on the evolution of female ornaments:
Tobias, J. A., Montgomerie, R., & Lyon, B. E. (2012). The evolution of female ornaments and weaponry: social selection, sexual selection and ecological competition. Phil. Trans. R. Soc. B, 367(1600), 2274-2293.

For more information on male and female reindeer antler cycles:
Bubenik, G. A., Schams, D., White, R. J., Rowell, J., Blake, J., & Bartos, L. (1997). Seasonal levels of reproductive hormones and their relationship to the antler cycle of male and female reindeer (Rangifer tarandus). Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology, 116(2), 269-277.