We started the semester with a course in animal reproductive physiology, which I really enjoyed. I just found it fascinating to concentrate on all the differences between species--reproduction is one of the areas where animals differ the most--I mean, it really runs the gamut! There are species of birds and lizards that don't even need to mate to reproduce (parthenogenesis). Female reproductive cycles are crazy different, but I'm going to concentrate on the interesting male reproductive organs that animals have. See if you can guess what these critters are just by their nether regions. Fun Game! Answers below with interesting facts too.
1. Hob (male ferret).
2. Drake (male duck)-did the feathers give it away? Not all birds have a copulatory organ (it's not a penis because there is no urethra), but waterfowl and ratites do.
3. Dog-believe it or not, this is not an abnormally large engorged penis. Looks like it hurts to me, but the beagle doesn't seem to mind. You can see the enlarged part near the belly--it's called the Bulbis Glandis and it swells inside the female's vagina and causes the "tie" while the semen ejaculates over several minutes.
4. Buck (male goat)-what's that worm on the end? It's not a worm. It's a urethral process and rams have it too. The cervix of does and ewes has muscular rings, and it is thought that the urethral process navigates these cervical rings to deposit semen right into the uterus. Interestingly, it can be snipped off if it gets plugged up with calculi without detriment to reproduction.
5. Beef Pizzle. Yuck! People eat bull penis and call it beef pizzle to tame the idea of where it came from.
7. Tom (male cat). See the little spines on it? A neutered cat loses these spines. It is thought that these spines help stimulate the queen (female cat) during intercourse (have you ever heard how she screams?!). This may be important because cats are induced ovulators (they don't ovulate unless they have sex).
8. Stallion-they are collecting semen from him. Takes so many people to collect, phew!
9. Llama-the female llama (and all camelids) have a bone in their cervix, which is unique in the animal kingdom. Because the llama penis deposits its small semen load directly into the uterus, the cartilagenous tip is there to make sure it's hard and strong enough to traverse the hard os cervix. Llamas have sex for 45 minutes or so, and do it in a prone position. Like the cat (and ferrets too), they are induced ovulators.
10. Lizard-in the reptiles that do have copulatory organs, many of them have 2. They are called hemipenes, and this is one of them. Interestingly, snakes have sex for up to 20 hours at a time. Whoa.
11. Boar-this fellow (the man) is collecting semen from a boar. He doesn't have to 'jack him off' but just hold his hand there with pressure. Boars ejaculate an enormous volume of semen, and so the gel fraction is being separated so as to collect just the sperm-rich fraction. The next picture shows the proud result of that collection. You can't see it in this picture, but the tip of a boar's penis is corkscrew shaped in order to 'thread' the screw-shaped cervix of the sow. Curlyque penises and curlycew tails too.