 |
| Pistol Shrimp |
A group of marine scientists wanted to figure out the details of these shrimp and their gunshot-like noises. It turns out that the shrimp is forcing out still water from in-between their claws and that creates a vortex-like motion. This swirling vortex that comes from the claw creates a void in the center and as it travels that void will collapse. The whole process happens in just a short time, less than half a millisecond to be more precise, but the vortex can travel as fast as thirty meters per second. One researcher said that you wouldn’t want to stick your hand in a tank with one because the force does hurt rather badly.
These shrimps are only known to grow to about five centimeters in size so they’re gunshot vortex is only useful against other individuals with a similar size. They don’t use this technique to stun prey or anything in that manner. This is due to the fact that these shrimps are scavengers that feed mostly on what they can find laying on the ocean floor. They typically are known to do this if they are trying to protect a mate or their homes. When two pistol shrimps duel it out these shockwaves aren’t fatal to them, but it will leave some puncture wounds and can even tear off a claw. These tiny underwater gunfights can still cause some potential damage.
References:
Woodward, A. (2017, October 27). How a tiny shrimp fires a savage shock wave using just its claw. Retrieved January 28, 2018, from https://www.newscientist.com/article/2151700-how-a-tiny-shrimp-fires-a-savage-shock-wave-using-just-its-claw/
I thought this was such a cool post because I have never heard of these shrimp before. It's amazing that such a small animal can create such a loud sound. I did some digging and found a podcast from Radiolab that actually talked about these shrimp. As the podcast discusses, the snapping sounds are so loud that they could interfere with sonar and were picked up by submarine transmissions. After discovering the source of the sound, Naval submarines during WWII actually hid in these shrimp colonies. This allowed them to go undetected from the Japanese. They also used speakers to play the snapping sounds out into the water to interfere with Japanese sonar. The podcast also discusses how the sound is created by the collapsing of a vortex. This was discovered using a high speed camera and fixing the shrimp to a platform. The bubble can move at 60 miles per hour and raises the temperature to 5000 degrees. The podcast can be listened to here at http://www.radiolab.org/story/bigger-bacon/
ReplyDeleteInterestingly, the pistol shrimp is not the only shrimp to use this method of protection. The much larger mantis shrimp also uses the collapse of cavitation bubbles to defend itself and kill prey. The shockwaves produced are so strong that they can be fatal even when they miss, and the energy released is enough to produce bright flashes of light. Along with their tendency to eat in a tank, mantis shrimps can crack and shatter aquarium glass. Despite being of different orders, the mantis shrimp seems like a larger and more colorful pistol shrimp. The Oatmeal made an excellent infographic about them, with links and videos at the bottom for more information: http://theoatmeal.com/comics/mantis_shrimp
ReplyDeleteI love that Oatmeal graphic. I accidentally stuck my hand in a bucket of fish that also had a mantis shrimp in it, but luckily it did not decide to break my finger!
DeleteBefore applying for college, I was very much interested in all animals, from small amphibians, lizards, and rodents to large elephants, bears, and cats. I was browsing on YouTube and found a National Geographic video on Pistol Shrimp. I showed my family members the video, who found it fascinating, and found that they had never heard of it before! What they thought was cool was that it also uses the shock wave to stun prey before it can then kill and eat it.
ReplyDelete