At first glance, one might overlook the peacock mantis shrimp as just another beautiful ocean dwelling creature. Although they are tiny, only coming in at between 10 – 15 cm (4 – 6 inches) in length, these amazing little creatures actually have superhero-like abilities that are straight out of a comic book.
With a ferocious temperament and highly complex vision, as well as beautiful coloring and deadly strike ability, the mantis shrimp are fascinating creatures.
They are common in Indonesia’s waters but remain quite poorly understood because they tend to be solitary and spend a great deal of their time tucked up in burrows on the seabed.
Sighting one of these spectacular shrimp on a dive is a treat for any visitor to Indonesia, but it’s twice as great once you realize just what special and unusual creatures they really are.
Species: Mantis shrimp aren’t actually shrimp at all but marine crustaceans of the order Stomatopoda. There are more than 450 different subspecies of mantis shrimp.
Appearance: Most mantis shrimp are brightly colored with hard shells that come in a wide range of colors. They have huge eyes that move around on stalks. Their eyes are some of the most complex ever discovered of any species.
Size: Mantis shrimp are usually around 10 cm (4 in) in length but can grow up to 38 cm (15 in).
Lifespan: The Mantis Shrimp usually live for between 3-6 years, but some species have been known to live up to 20
Diet: They eat soft-bodied prey such as worms, fish and squid, or hard-shelled prey including clams, crabs and snails. They often attack prey much larger than themselves.
Temperament: These little creatures are incredibly aggressive – and they have the tools to back it up. They tend to be broadly categorized into two groups – the “Spearers” and the “Bashers.”
The “Spearers” have barb-like points at the end of their front arms, and they tend to spend their time lying in wait for prey in their burrows and ambushing them when they get too close. “Bashers” have club-like ends to their arms. They are less common, and they often go in search of their prey and use their incredible club-punch to bash hard-shelled prey.
Habitat: Mantis shrimp tend to live in rock formations or burrows in the seabed.
Getting to know the mantis shrimp isn’t just a way to connect to the beauty of the ocean and the enormous amount of fascinating creatures that it holds – it can also be something that directly helps humans.
For example, did you know that mantis shrimp’s eyes are so powerful that they can even see cancer?!
Researchers at Queensland University have studied mantis shrimps eyes to see how they detect polarized light. Humans and almost all animals can’t see polarized light, but mantis shrimp can. Why is this important? Because unlike healthy tissue, cancerous tissue reflects polarized light differently.
By modeling how the mantis shrimps eyes work the researchers have developed a camera with the same characteristics as their eyes, which will allow scientists to detect and monitor cancerous tissue in human patients.
Studying their eyes has also bought scientists closer to developing new ways to build DVD and CD players by inspiring new ways to see light and process movement.
As you can see, there is much more to the Mantis Shrimp than just their tiny size, so, let’s investigate this amazing creature in more detail.
Their compound eyes are made up of thousands of tiny parts that detect light. These light-detecting cells are called ‘photoreceptors’ and the mantis shrimp has an amazing 12 – 16 of them. Humans, in contrast have 3, red, green and blue!
They have three pupils lined up in a row and each one scans the environment to see. It was thought that due to the extra receptors Mantis Shrimp could see more colors than humans, but experiments showed this wasn’t the case. In fact, despite the amount of receptors they have, they appear to see a similar amount of colors to humans.
So if these receptors aren’t for seeing extra colors, what are they for? Why do they have such complex eyes?
The short answer is, we still don’t know for sure. However, researchers have been studying Mantis Shrimps eyesight and now believe that the extra receptors may be a way of allowing it to process images it sees very quickly without much input from its brain. This could make sense given how fast the Mantis Shrimp hits.
Another reason they might have such complex eyesight is potentially to communicate. Seeing polarized light could be a way that Mantis Shrimp signal to each other, by interpreting ultraviolet patterns reflecting off each other’s bodies.
Muhammad Ali might have been able to ‘float like a butterfly, sting like a bee’ but the mantis shrimp can move like a jet and smash like the Hulk!
Their famed punch is so powerful that it has the force of a .22 caliber bullet – reaching 50mph in 3 milliseconds. To put this into context, if a human was able to throw a baseball with the same speed and force the ball would go into orbit! When a mantis shrimp strikes its prey with this devastating blow it literally smashes the prey into pieces – taking down crabs, octopi, mollusks and oysters.
A key to the mantis shrimps aggression is in their name. Like the preying mantis, these creatures are fiercely aggressive and ruthless killers. One of their nicknames is even the “thumb splitter” because if not handled correctly they can inflict gashes on humans. In fact, their claws are so powerful that in some cases when kept in captivity they can even break aquarium glass.
You might think that having such a powerful punch would be enough to put them top of the list for scary kill capacity- but they have another amazing way of taking out their prey.
Because mantis shrimps can move so fast – in the time it takes you to blink your eye they could theoretically punch 500 times – it creates a phenomenon called “supercavitation.” As the mantis throws its claws out, the speed of causes the water around it to boil in little bubbles. When the cavitation bubbles collapse it sends out a shockwave that can kill prey, even if the punch itself misses.
Since the mantis shrimp are so powerful it seems logical that they would avoid fighting with each other, but researchers have discovered this isn’t the case at all.
Mantis shrimps have been observed landing blows on each other in what is thought to be a ritual fight to test each other’s speed and stamina. The shrimp will deliver blows to each other’s tailplate called a ‘telson,’ hugely tough pieces of armor that protect them from having their shells pierced.
The mantis shrimp will hit each other over and over again and researchers believe that this is a way of figuring out who is the strongest. In some cases a victorious shrimp will hit out again at the loser as it tries to flee – seriously injuring or even killing it.
Because of their incredible aggression and solitary nature it’s easy to see mantis shrimp as just tiny killing machines. But some mantis shrimp are monogamous – staying with the same breeding partner for up to 20 years. In this sense, they could be considered lovers as well as fighters.
These mantis partners share the same burrow and appear to coordinate their activities together, just like a married couple. Some might breed 20-30 times together during their lifespan and lay their eggs in the same place over and over again.
Despite starting to understand the mantis shrimps vision and their superior punching abilities, we still know relatively little about the rest of their lives. It just goes to show that even the tiniest creatures in the ocean can be highly sophisticated and intelligent beings, with their own superhero like abilities, relationships and social structures.
Next time you’re on a dive and see a mantis shrimp, try to observe its behavior and determine what it’s doing on that day, and marvel at what a complex and special creature it is.