If you're an average person and not some kind of jizzologist, you may not have given much thought to how sperm actually works. Luckily, scientists have — and now they're telling us that sperm is actually intelligent. Specifically, it seems to be able to count.
In a study published in the Journal of Cell Biology, (via ScienceDaily) researchers looked at how sperm swim. Their strokes seem to be controlled by the calcium concentration in their environment (which, if they're lucky, I guess is a uterus). Originally, scientists thought it was the amount of calcium that mattered. Oh, but sperm are slicker than that. They actually change the way they swim based on how fast the calcium concentration is changing. Which means they have to know how fast it's changing — "to put it simply: sperm can count!"
Why do sperm need time-counting ability? The study authors think it's because calcium concentration gets really high close to the egg — measuring small changes in concentration may help them react even when there's lots of calcium around. That is, their counting helps them when they're close to the goal and their decisions matter most. If you can call them "decisions." Scientists aren't totally sure how sperm count, since of course they don't have brains. In that way, they're a lot like Beavis.