no clue where on earth this should go.
i'm watching some thing on yellowstone on iplayer (not much to do atm :/)
and it was saying when wolves mate, they are locked together for upto half an hour, unable to break free.
when i was younger i remember a similar thing happening with one of our dogs in kenya.
how does this locking mechanism work!!! and how on earth is a locking mechanism evolutionary favourable
Stops the female getting away.
I suppose if they are locked together there is a greater time for mating to be successful. However I also watched yellowstone and it does make them very vulnerable.
the penis swells and the vagina constricts, hence the two are locked together. this:
enhance sperm and ovum transport
mateguarding function to prevent sperm competition
Reminds me of years ago, I went on holiday and my dog, still at home, went to find himself a shag. I was told on my return by the teary eyed and bewildered owner of the female my dog chose to mate with that after my dog had mounted her they tried to prise them apart but to no avail. The owner was about 8 years old, think the whole thing affected him psychologically. Gutted.
The dog's penis swells into a bulb shape so that it is locked into the *****'s vagina. The dog then generally gets off her and turns around so that they are bum to bum. It's called the tie and turn. No real evolutionary advantage, just one of those things. If this interests you, you might also be interested in the spikes tomcats have on their penis, which spike the female on the pull out and stimulate ovulation.