I was curious so I went and googled it and found the following: "Sperm thrive in lower temperatures. Ideally, they should only be exposed to 4° F below body temp (roughly 94°) or cooler. This means that even small sources of heat can start to add up and damage your sperm count." Quick google search would do you the same but for the sake of it, the answer is cold conditions
it is unique in being the only human bone that is not attached by joints to any other bone, but is suspended in the neck by muscles and ligaments alone.
