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March 21, 2013
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Credit: VA Institute of Marine Science (VIMS)
There’s nothing like the thought of a delicious piece of meat with human teeth wrapped in prison stripes to put you to a gentle, dreamless sleep.
Despite the way it looks, the sheepshead fish (Archosargus probatocephalus) has at least one thing going for it. While other members of the Sparidae family are trying out various forms of hermaphroditism, including changing from female to male (protogyny), doing the opposite (protandry), or being unisexual (gonochorists), the sheepshead is just sitting at home watching cartoons and leaving its genitals where they are. So that’s something.
Sheepshead incisors. Credit: Glen J. Kuban
Another good thing about this huge creep is that, unlike one of its relatives, the Salema porgy (Sarpa salpa), you won’t risk having a terrible trip when you eat one. Apparently they taste great! The Salema porgy, also of the Sparidae family and nicknamed the dreamfish, was reportedly used for recreational hallucinogenic purposes in the Mediterranean during the Roman Empire and has played a role in traditional Polynesian ceremonies. Along with a handful of other fish, the flesh of the Salema porgy can sometimes inflict ichthyosarcotoxism on those who eat it, which is a very rare form of poisoning caused by the toxins of a tiny species of marine plankton called Gambierdiscus toxicus. This poisoning from contaminated fish flesh prompts intense hallucinations and terrifying nightmares that can last for several days.
As reported by Luc de Haro and Philip Pommier from the Centre Antipoison of the Hôpital Salvator in Marseille, France, in a 2006 issue of Clinical Toxicology, a 90-year-old man ate a Salema porgy in Saint Tropez in 2002 and two hours later was hallucinating and having nightmares about people and birds screaming, which lasted a further two nights. He literally thought he was losing his mind. “Fearing that these symptoms might signal the beginning of a major mental illness, he did not tell his friends or attending physician. The manifestations abated three days after he had eaten the fish,” de Haro and Pommier report.
Prior to that, a 40-year-old man also fell victim to ichthyosarcotoxism while holidaying in the French Riviera and had hallucinations of screaming animals and giant, menacing spiders surrounding his car. In 2009, a fisherman named Andy Giles caught one in the English Channel, which is unusual because they usually keep to warm waters of the Mediterranean and African west coast, and told the Daily Telegraph, “Now I realise what it was and the effects it can have, perhaps I should have taken it into town to sell to some clubbers!” Andy lol.
So the sheepshead fish doesn’t do any of that stuff. But it does have human teeth. Sheepshead fish are a common North American marine species that span from Cape Cod and Massachusetts through to Florida and the Gulf of Mexico to Brazil. Preferring coastal habitats around rock pilings, jetties, mangroves, reefs and piers, they can grow up to around 91 cm in length and weigh up to 9.6 kg. They have five to seven distinctive black, vertical bars running down their silvery bodies, which is why the sheepshead is also called the convict fish. And true to their name, sheepshead fish are notorious for stealing bait and somehow being in cahoots with the Joker.
Look at these criminals. Credit: mentalblock_DMD; Flickr
A fully-grown adult sheepshead will have well-defined incisors sitting at the front of the jaw, and molars set in three rows in the upper jaw and two rows in the lower jaw. It has strong, heavy grinders set in the rear of the jaw too, which are particularly important for crushing the shells of its prey. As with humans, this unique combination of teeth helps the sheepshead process a wide-ranging, omnivorous diet consisting of a variety of vertebrates, invertebrates and some plant material.
Credit: Texas Parks and Wildlife Department
When they’re young, sheepshead fish will eat marine worms, bryozoan ‘moss animals’ and pretty much anything soft-bodied they can catch in the seagrasses. Although thick, sharp teeth begin to appear when a sheepshead is just 4.5 mm long, it will have to wait until it’s about 15 mm long before all the incisors have come in and the back teeth begin to develop into adult molars. Once they reach around 50 mm in length, the sheepshead will advance to eating more robust, armoured prey such as echinoderms, barnacles, clams, crabs and oysters, using their highly specialised teeth.
During this stage, its jaw musculature is also developing, and this keeps improving right through to old age. So an old fish living around a good supply of hard-shelled prey will end up having much greater jaw crushing power than a younger fish in a less rich environment. “Evidence strongly suggested that oral jaw crushing force was an important determinant of diet in these fishes,” said L. P. Hernandez from the Museum of Comparative Zoology at Harvard University and P. J. Motta from the Department of Biology at the University of South Florida in a 1997 issue of the Journal of Zoology. Hernandez and Motta had been observing the oral crushing performance of sheepshead fish from birth through to adulthood. “There was a significant correlation between increased force production and increased durophagous [shell-crushing] habit. Studies such as this one speak directly to the relationship between maximum functional potential and actual patterns of resource use.”
It’s not clear why the sheepshead is called the sheepshead, but it’s been suggested that it refers to how its teeth look like sheep’s teeth. A quick Google and cursory glance over some disgusting farm teeth, and I don’t really see the comparison, but another suggestion is that the name relates to their silhouette. And there’s something to be said for a sheepshead fish that has managed to keep its silhouette looking as non-offensive as it does, because look what happened to the Asian sheepshead of the Labridae family.
Here’s a video of some very American men with a live sheepshead:
****
My book, Zombie tits, astronaut fish and other weird animals, will be released in the US next month, and is available for pre-order from Amazon now.
About the Author: Becky Crew is a Sydney-based science writer, award-winning blogger and former online editor of COSMOS magazine. She is the author of 'Zombie Tits, Astronaut Fish and Other Weird Animals' (NewSouth Press). Follow on Twitter @BecCrew.
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That fish freaked me out with those teeth the first time I caught one, at night, alone. Then I cleaned it. The head makes up half the fish, and the lining of its gut is black. I can tell you it gave me bad dreams that night.
Link to thisInteresting.
Thanks
Link to thisWhat about the Southern California sheephead? The one with orange and black markings. My grandmother loved to eat them. I once ask my biology teacher if the sheephead teeth were similar to human teeth and he said no. I guess science has progressed a bit in the past 40 years.
Link to thisThe California sheepshead has great teeth too! http://www.flickr.com/photos/marlinharms/6206164117/
Link to thisThe one in California has teeth more like a cousin from the Appalachians than this fish. They have larger gaps and more canine-like appearances. These change from female to male too. Then they get speared by people (I used to be guilty of this) but they’re really not all that good to eat and I’ve tried many different ways including recipes that make them taste like “lobster” or so the author said. Large males are really rare because they’re such an easy target. I have photos but can’t upload them here.
Kelp Bass taste much better and since they’re only “sport-legal” most people never get to eat one. Better than sole or any other fish I’ve eaten. More difficult to shoot too.
California Sheepshead eat a lot of urchins too. I think they use their teeth to pick the spines off them which they usually spit out. If they can turn the urchin over then they can pierce the shell easier.
Once when I was collecting brittle stars for a client a small octopus was injured and it bobbed up and down for about ten seconds until a large male sheepshead swam up and swallowed it. I heard a distinct crunch, probably from the hind teeth but they’ll eat octopus too it seems. Everything else does too I think…
The convict fish looks a lot like Sargo, a grunt that swims by in large schools sometimes. I actually speared two when I was a teenager and heard grunts in stereo which freaked me out until I laid hold of the spear and felt it vibrating. Then I knew where the sound was coming from.
Another really weird fish meal you can find these days, of dwindling catches, are the fish that cause diarrhea, the Escolar. Boy do I love fish. Even stranger than humans, though I never ate one of those either. I’m sticking with halibut!
Link to thisRight because every video of “very Australian” men shows them to be refined and worldly by comparison.
http://youtu.be/2LD4hwqsgBc
Link to thisCome on ..Can’t the people in the White House ..keep Joe Biden away from the Fish Tank ???
Link to thisIt’s not an insult, I meant it in an affectionate way. I love seeing Americans with great accents having a great time and being enthusiastic. I’m a big fan of it.
Link to thisWouldn’t it be more accurate to say the fish has teeth that resemble human teeth? Unless someone has done surgery on them, how could they have human body parts?
Link to thisHey you progressive liberal socialist b*t*hes,give us real americans a rest on the metric silliness your trying to force down our collective throats. We are totally happy with our standard measurement system and don’t need to be euro trashified!
Link to thisAll I have to say is…
http://zeph-online.net/files/wtf.gif
Thanks.
Link to thisNo apologies necessary Ms. Crew. I am a proud American who has a southern accent and thick skin…unlike some of my fellow countrymen. Thank you for appreciating the “finer” things in life.
Link to thisThat’s a great name, Ashland Dog.
Link to thisThere is a much clearer picture of the teeth of the Sheepshead Rivicarus species at this site: http://www.welaf.com/13415,ugliest-teeth.html
Link to thisCaught one in Mobile Bay in a row boat,It towed us all around the bay before i could land it !!
Link to this“nightmares about people and birds screaming, which lasted a further two nights. He literally thought he was losing his mind”
Link to thisFunny, I have a Congo African Grey that does that every day!
We rescue Collie Dogs Ms. Crew currently we have 10 looking for homes, so the screen name kind of came naturally. OBTW very interesting article, they have it linked in the Drudge Report so you have hit the BIG TIME! LOL
Link to thisMs. Crew,
Are you familiar with the bay in the NYC area (Borough of Brooklyn) named after the Sheepshead fish? I lived in Sheepshead Bay, Brooklyn for ten years growing up with my parents, younger brother and family friends. It was once a large part of the fishing industry of NYC, and now is just a quiet neighborhood that is recovering from the devastation of Hurricane Sandy.
Link to thisMy skin is plenty thick as well, Ms. Dog. My problem is that I’m easily offended.
Thank you for the well-written and interesting article…And for giving metric system guy a forum to release all of that angst.
Link to thisPerhaps you need to add another layer to your berqa Ms. Habeebjab. One who has thick skin, in American parlance Ms. Habeebjab, is not easily insulted.
Link to thisThat is one tasty fish. They are hard to clean but well worth the time.
Link to thisMs. Dog: Perhaps you could explain some more, I still don’t understand. Probably because of my race, as you implied. How does this thick skin of yours sheild you from offence?! If I could learn this secret I would gladly drop my (inadequate) burqa.
Link to this