rhamphotheca:

Why a Swordfish’s Sword Doesn’t Break

by Carrie Arnold

A swordfish’s “sword” is its most prominent feature, but scientists have only now discovered the unusual properties that keep the sword strong and ready to slash.

A study published Monday in the Proceedings of the National Academy of Sciences reveals that the fish have an unusual way to repair their bone, keeping it strong and stiff.

Billfish like marlin and swordfish are known for their characteristic protruding upper jawbone (also called a rostral bone), which they use to help stun and catch their prey.

For the bone to remain strong, it needs to not only withstand a large amount of force, but also be repaired when it is damaged…

(read more: National Geographic)

photograph by Brian Skerry/National Geo.