I like finding freaky animals. I just think they’re neat. It’s so much fun to see the variety of animals that we have on this earth. So, when my friend asked if I had ever written about a shark, I took it upon myself to find the freakiest shark possible: the goblin shark (Mitsukurina owstoni).
Goblin sharks are what is known as a living fossil. They are the last living member of the Mitsukurina family; the other species have since gone extinct. This family dates back to 125 – 113 million years ago. In all this time, the goblin shark has really not changed much, and still exhibits a lot of the original traits of this ancient family.
Unfortunately, we don’t know much about goblin sharks. They live in extremely deep ocean water, and most of the interactions we have are from goblin sharks getting caught in fishing nets. The few specimens that have been caught alive died shortly after being brought to an aquarium. Still, we can learn a lot with data we do have on their behavior and by examining their body structure.
- What’s in a name?
- Goblin sharks have been found in 3 major oceans across the world: the Atlantic, Pacific, and Indian Oceans. However, they are most commonly encountered off the coast of Japan. It is from Japanese fishermen that we get the name “goblin shark.” The long snout of the goblin shark reminded the fishermen of the long-nosed, red-faced Japanese demon called the tengu. So, they named the shark tengu-zame, with zame meaning “shark” in Japanese. We translated this name into English as “goblin shark.”
- Live young (probably)
- We don’t know for sure how goblin sharks reproduce; we’ve never found a pregnant female. However, we can make some assumptions based on the fact that goblin sharks are related to mackerel sharks. Like other mackerel sharks, goblin sharks are probably viviparous. This means that they give birth to live young. However, unlike most mammals, goblin sharks likely do not use a placenta to nourish their young. Instead, mother goblin sharks likely provide their embryos undeveloped eggs to eat in what is called “oophagy.”
- SO MANY TEETH
- Goblin sharks have a frighteningly large amount of teeth: between 35 and 53 on the top jaw, and between 31 and 62 teeth on the bottom. Remember, humans have only 32 teeth; goblin sharks literally have at least double the teeth we have. They have so many teeth that their teeth are still visible when their mouth is closed. Goblin sharks have taken the opportunity to have different teeth specialized for different tasks. The teeth in the main part of their jaw are needle-like: long, narrow, and sharp. In contrast, the teeth in the back of their mouth are smaller and flatter. These teeth are used for crushing.
- Ambush predator (probably)
- We think, based on their body, that goblin sharks are not great swimmers. They are pretty flabby and have small fins, both of which suggest that they can’t swim particularly quickly. So instead of chasing their prey, goblin sharks probably rely on ambushing them. The long snout of the goblin shark is likely used to find prey: it contains lots of ampullae of Lorenzini. These are sensory organs that detect the electric fields produced by living creatures. Once the goblin shark finds its prey, they slowly drift towards it with minimal movement.
- Slingshot feeding
- Okay, so the goblin shark has snuck up on its prey; how does it capture its lunch? By slingshotting its jaws forward. Goblin shark jaws are held retracted in the mouth by elastic ligaments; when the shark bites, the ligaments release and the jaws shoot forwards. And they shoot forwards a LOT: a distance of 8.6 to 9.4% of their body length. For comparison, this would be like if we could shoot our mouths forward 7 inches. Other sharks can also protrude their jaws, but goblin shark jaws get the gold medal for protrusion: they can protrude 2.1 – 9.5 times further than other shark jaws.
- In addition to the length goblin shark jaws can reach, they move incredibly quickly: 10.1 feet per second, or 6.9 miles per hour. And on top of THAT, the jaw opens to an 111-degree angle. All of this adds up to let goblin sharks snag its prey before they have a chance to blink. You can watch the goblin shark jaw at work here.
The good news is that even though they look freaky, humans don’t have to worry about goblin sharks. First, they really only eat soft-bodied fish and squid; humans are not on the menu. And second, it’s super unlikely that we would ever come into contact with a goblin shark. They live deep underwater, usually remaining 885 feet to 3150 feet below the surface. And they probably go deeper than that: a goblin shark tooth has been found in a cable 4,490 feet underwater.
Maybe one day when we can dive that deep, we’ll be able to see a goblin shark in action.
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