Ignoring huge variables like sex is not the best way to get valid data.

BIOLOGY
This butterfly-shaped gland influences every cell in your body.
The venom of the baby brown snake is neurotoxic, while the adult snake’s venom causes internal bleeding and strokes.
A single cell can be used to restore an entire mammal circulatory system.
Love them or hate them, there’s no denying that the creepy crawlies are an amazingly successful bunch, with over 1500 known species lurking about.
Your tongue isn't just important for tasting. Here are a few underappreciated facts about the most flexible muscle in your body.
<em>C. elegans</em> nemotodes respond to exercise in very similar ways to humans.
Researchers used a CT scanner to watch how dolphins' oddly shaped junk fits together during sex.
The drug manipulates the expression of a specific gene associated with the disease.
These microscopic monsters just get weirder and weirder.
We're still learning about one of the most important structures of the brain.
You're probably aware of some vestigial body parts, like wisdom teeth, that the human body doesn't really need. But did you know there are several muscles in that category as well?
The world is teeming with life, and we're always discovering new species—including some that stretch the limits of how we view and classify biological life forms. Here are a few that clearly don't play by the rules.
8. You might want to rethink an ankle tattoo.
Bird poop has been a favored fertilizer for centuries—and, it turns out, is an excellent preserver of human flesh.
Dysfunctional gene expression may make some people hypersensitive to sex hormones like estrogen and progesterone.