大象传媒

Chris Packham has a plate full of snails - live ones. Because they have lots of different colours on their shells - yellow, pink, brown - you might think that they are different species. But in fact they are all banded snails. Why are there so many colours in this species? It is simply that the snails want to live in as many habitats as possible, and avoid the predators there. So a brown one would be better camouflaged than a yellow one in woodland and therefore less predated. But a brown one would be more conspicuous than a stripey one in the grass. So there are different coloured individuals in different habitats. The dark colours also warm up faster in the sun, so it will be active earlier and longer, giving it more foraging time and making it fitter.