Wasting wood is a serious problem in conserving the resources, which are distrib

Throwing away food means wasting the resources used in its production, such as water. This is especially foolish in dry countries such as Spain. The problem is set to get worse as climate change makes rainfall patterns less predictable.

The idea that the brains of mammals make a mental map that mirrors the spatial geometry of the outer world first emerged around 1930. Neuroscientists have subsequently identified cells that work together to create such maps. A key development came in 1971, when an American-British researcher found that place cells in the rat hippocampus fire at particular locations on the willy-nilly path an animal travels.