Almost nothing in the animal world does what this does.
A great many animals signal. They warn, threaten, court and call, and the signal refers to the here and now…
The test is simple: pigment colour looks the same from every angle, and structural colour changes as you move. Once you know that, a great deal of the natural world…
Ice cubes float. This is so ordinary that it takes a moment to see anything strange in it.
Consider what floating means. An object floats when it is less dense…
The fossil record is overwhelmingly a record of hard parts.
Bones, teeth and shells survive because they are mineral to begin with. Everything else — muscle, skin, fur, feathers, gut…
Almost none of these are about a single person doing a small thing. They are about what a small thing becomes when several million people do it in a year.…
The feature that makes a fjord a fjord is the sill at its entrance - a shallow threshold of rock and debris left where the glacier terminated. Water inside is…