Eggs-actly

This picture is part of a scientific Easter-egg hunt. “Egglab” tries to recapitulate the evolution of crypsis in nightjar eggs by asking the public to act as predators and play “spot the egg” in photos of places where these ground-nesting birds might lay their clutches. A computer generates the initial eggs (oval shapes whose colours and patterns are chosen at random and superimposed on the image) and the player has to find them. Those it takes longest to find are then mutated slightly and crossbred to create a new generation. After ten generations the result can, as the picture shows, be quite cryptic (spot the one artificial egg). Martin Stevens of Exeter University, in Britain, who devised the game, hopes to use it to study selection pressures on real eggs.

Readers who wish to play can do so here