The birds and the bees may have their own tune, but when it comes to sex in the animal kingdom, whales put on quite a show. We've witnessed an underwater display from a pair of mating greys before, but during a recent encounter off the coast of Argentina, a group of right whales took things top-side, giving us an even closer look.
(Things get a bit NSFW from here; pass "go" at your discretion.)
Southern right whales boast some of the largest penises in nature. At a maximum length of four metres (12ft), their mighty members set the record among the rorqual (filter-feeding) whales. But it doesn't stop there: the penis is coupled with a pair of one-tonne testicles, which produce about a gallon of sperm at capacity.
While it might seem gratuitous to dwell on size, in the whale world, size matters. Watching the recent mating display off Argentina's Valdes Peninsula, it's easy to see why.
"These animals visit [the area] to reproduce, and give birth to their young," explains photographer Mariano Jedrzejewski, who captured the mating whales on film earlier this month. "The spectacle leaves those who have the privilege to visit filled with admiration."
On this particular day, Jedrzejewski and a group of astonished onlookers witnessed three males battling it out for the right to breed with one female. It's no easy task: female right whales are known to go belly-up in an attempt to keep their genitals away from unwanted suitors. For the determined males, wielding their supersized anatomy gives them a greater chance of reaching their target.
The whale's penis is also surprisingly agile, controlled by two muscles anchored around the pelvis. By pulling with varying degrees of tension, the muscles not only give the penis a good range of motion, but they also allow it to change shape based on the entry angle and the anatomy of the target female. In other words, one size does not fit all, and a pelvis-powered, prehensile penis can easily adapt.
We've only recently started unravelling the connection between a male whale's pelvis and sexual bravado. Because these animals lack weight-bearing limbs, scientists previously assumed the pelvis served no purpose, being nothing more than an evolutionary leftover (much like your tailbone) from the group's four-legged ancestors, the "walking whales".
Then, a 2014 study showed that in species with a high level of breeding competition, the pelvis – typically tiny and quite straight – was both large and curved. A closer look revealed that whales with such plus-size pelvises also had bigger penises and testicles. This suggests that a bit of skeletal support may actually give the animals better control of their kit, and in turn, some help in the sperm-delivery department. (In case the age-old question plagues your mind: no, whale sperm did not make the ocean salty.)
Prefer something you can safely watch at the office? Here's a gorgeous drone clip of mating right whales in Australia:
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Top header imgae: muzzanese, Flickr
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