Thanks to their tough shells, coconuts are notoriously difficult to consume – so you don't earn yourself a name like the coconut crab unless you've got a real knack for cracking them open. For the first time, scientists have quantified the force behind the mighty pincers that these creatures use in their meal preparations, finding that not only does the coconut crab have the strongest pinching force of any crustacean, its claws might match it with the jaws of most land animals, too.
Coconut crabs carry quite the reputation in the world of crustaceans. As the largest among terrestrial crustaceans, they can lift up to 28 kg (61 lb) and use their beastly claws to fend off attackers, while claiming a monopoly on food sources like coconuts and other goodies with tough exteriors.
Looking to gauge exactly how much force these beastly pincers can exert, researchers from Japan's Okinawa Churashima Foundation rounded up 29 wild coconut crabs from Okinawa Island, Japan, ranging in body weight, and analyzed their claws in action. The force varied from 29.4 to 1,765.2 newtons, and the scientists observed a strong positive correlation with body mass.
Based on this, the team projects that the largest coconut crab, weighing 4 kg (8.2 lb), can exert a force of 3,300 newtons. This is around 10 times the average human handshake, about four times the force you'd generate when biting into a steak and about 75 percent of the force hyenas, tigers and lions generate with their jaws. Indeed, the team says it exceeds the bite force of most terrestrial animals. So if you see one, best keep your hands to yourself.
The research was published in the journal PLOS One.