Most birds lack a penis—both sexes mate by pressing a sin... | funfact.wiki | funfact.wiki
Most birds lack a penis—both sexes mate by pressing a single opening called a "cloaca" together. Ducks are an exception: their corkscrew-shaped penises can reach 42.5 cm, rivaling their body length. Unlike mammals, they achieve erection via lymph fluid in about one second.
Menthol makes your mouth feel cool without changing the actual temperature. It raises the activation threshold of cold receptors, making you perceive coldness at temperatures that would not normally trigger it.
Newborn horses don't have hard hooves. A jelly-like covering called "foal slippers" wraps around their hooves, protecting the mother during pregnancy and birth. These coverings naturally fall off once the foal begins to stand and walk.
Walking with same-side arm and leg moving together (lateral walk) is actually the most common gait among mammals — dogs, cats, elephants, and deer all walk this way. In Edo-period Japan, people also walked this way, using a style called "nanba."