LEWIS CASEY, PORTSMOUTH
WHY DO SNAILS MOVE SO SLOWLY? IS THERE AN EVOLUTIONARY ADVANTAGE TO THEIR LACK OF PACE?
Slugs and snails use a ‘ventral foot’ – a long, slimecovered muscle on the underside of their bodies – to move at speeds of around one metre per hour (three feet per hour). The foot, or muscle, ripples to send the animal sliding over its own slime. This system is inherently quite slow and is limited by their rate of slime production.