How hermit crabs control growth to fit in their shells

Scientists have long known that hermit crabs control their growth to fit in their shells. Now we know how they do it.

New research suggests the answer isn’t simply that the crabs eat less. Instead, they appear to regulate growth by changing how efficiently they use the food they consume.

“Hermit crabs depend on empty snail shells for protection, and the right size shell isn’t always available,” says Cai...