This Is What a Shark Would Look Like If You Put It Through an X-ray Machine

If you think sharks are scary, wait until you see pictures of their skeletons.

Sebastien Enault and Camille Auclair of the organization Kraniata make a living cleaning, restoring and casting the bones of animals. As such, their company Instagram page is awash in skeletons of all kinds—including high-contrast images of fox, chameleon and peacock skeletons. There is even one of a stillborn bottlenose dolphin exhibiting craniofacial duplication.

The shark skeleton refurbished by Kraniata and pictured below is a short-finned mako (Isurus oxyrinchus), one of two living mako sharks. (The other being the long-finned mako.)

mako shark
Sebastien Enault and Camille Auclair of Kraniata make a living cleaning, restoring and casting the bones of animals like this one of a mako shark. Sebastien Enault & Camille Auclair/Kraniata Osteology

It has a striking resemblance to its more infamous cousin, the great white (Carcharodon carcharias). However, there are a few crucial differences.

For one, the mako is smaller, growing to lengths of 12 feet and reaching weights of 1,200 pounds in comparison to the great white's 20 feet and several tons. It is nimbler, too. The mako can reach top speeds of 45 miles per hour (74 kilometers per hour), making it "the fastest shark" and "one of the fastest fishes" alive, according to marine wildlife organization Oceana. This accolade has earned the mako the moniker "cheetah of the sea."

Scientists recently worked out how they are able to reach such speeds and reckon it might have something to do with their skin. Makos, like all sharks, fall into the subclass Elasmobranchii, alongside species of rays and skates. Animals of this subclass are covered in dermal denticles—tiny scale-like structures that resemble teeth more than they do fish scales.

Denticles have various functions, but one is to improve the shark's dynamism in water by reducing drag and, therefore, the amount of energy required to move through the sea—hence, Speedo's Fastskin, a material first developed in 2000 that uses v-shaped denticle substitutes to boost swimmers' speeds in the water. Those of the mako shark appear to be particularly flexible, studies have found. The translucent structures are just 0.008 inches long and sit loosely on the shark's skin, moving in response to the flow of water.

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The skeleton head-on, as if in attack mode. Sebastien Enault & Camille Auclair/Kraniata Osteology

Makos are migratory beasts that can be found in tropical and temperate locations across the world, including Florida.

While they are apex predators and top of the pelagic food web, preying on bony fish and squid as well as other sharks, marine mammals and sea turtles, makos rarely present much of a threat to humans. There have been incidents of mako sharks attacking—and even killing—people, but these are incredibly uncommon and a shark is unlikely to attack unless provoked. According to The Florida Museum, there have been 10 unprovoked attacks attributed to the shortfin mako, one of which was fatal.

mako shark
The mako shark is smaller and nimbler than its more infamous cousin, the great white. Sebastien Enault & Camille Auclair/Kraniata Osteology
mako shark
A side-on view of the mako shark skeleton. Sebastien Enault & Camille Auclair/Kraniata Osteology

Humans, on the other hand, pose a bigger threat to mako sharks—who are often targeted for their fins (a key ingredient in shark fin soup) or end up as collateral damage from fishers on the hunt for other species. The short-finned mako is listed as vulnerable on the IUCN Red List as population numbers continue to decline. This situation is exacerbated by the animal's slow maturity—while male sharks reach reproductive age at seven to nine years, females are not fully mature until they reach 18. Three-year reproductive cycles make the species even more sensitive to over-fishing.

In August, officials at the Convention on International Trade in Endangered Species (CITES) aimed to boost protections for the shark by voting to add makos to the species protected under the CITES Appendix II. This requires international trade to be managed through a system of various export permits and certificates.

shortfin mako
A living breathing shortfin mako. Alessandro De Maddalena/iStock