When an apple is sliced, damaged cells expose compounds inside the fruit to oxygen.
An enzyme called polyphenol oxidase helps drive reactions that eventually produce brown-colored compounds.
Acidic liquids such as lemon juice can slow the...
Capsaicin activates a heat-sensitive receptor in humans and many other mammals, producing the familiar burning sensation.
Bird versions of the receptor are much less sensitive to capsaicin.
This allows birds to eat fruits containing hot peppers...
When threatened, many geckos can detach part of their tail through a process called autotomy.
The separated tail can continue wriggling for a period, potentially distracting a predator while the gecko escapes.
A replacement tail can grow later...