The sheepshead fish has human-like teeth helps it consume an omnivorous diet.
Someone slap a lawsuit on the dentist who fitted this fish with the freakishly human teeth… What’s that you say? Evolution did this. By natural selection? What was it thinking!
The sheepshead fish, aka the lovechild of Billy Bass and my granny’s dentures, is a scaly, sparkly swimmer that can be found in the shallow waters of the western Atlantic, from Nova Scotia to Brazil. It’s a euryhaline species, which means it can tolerate a wide range of salinity.
While the fish usually lives in coastal waters and estuaries, they sometimes head to freshwater to find warmth in winter. In days gone by, the fish could be spotted in Brooklyn’s Sheepshead Bay, which was named after it, but then the Bay became polluted and the fish disappeared.
No one knows exactly why it’s called the ‘sheepshead’ fish, when its teeth are clearly the main event, but some say that its blunt snout and almost horizontal mouth are indeed sheep-like. Its grey and black stripes do, however, lend themselves to its alternative moniker of the convict fish. Put one in jail next to a prisoner in a striped uniform and it shouldn’t look like a fish out of water.
Freshly hatched sheepshead fish are tiny and toothless. They dine on soft foods, such as marine worms and plant matter. Their teeth start to come through as they approach 5cm (2in) in length, and from then on, the fish start to tackle more robust, shelled prey, such as barnacles, clams, crabs and oysters.
Adult sheepshead fish, which grow up to 75cm (30in) long, have three rows of teeth in their upper jaw, and two rows lining their bottom jaw. These include chisel-shaped incisor-like teeth at the front, and flatter molars and rounded grinders towards the back. All of which are coated in a hard, enamel-like substance, laid on top of a calcified dentin interior.
This seemingly motley collection of gnashers, which is not so different to our own, is an adaptation to the fish’s omnivorous diet. Evolution has selected for this arrangement because it enables the fish to bite, crush and grind, and exploit a rich variety of food sources. The sheepshead fish is known to eat more than a hundred different species. This is part of the reason why it has been so successful.
Another reason is that it has relatively little meat on its body and sharp dorsal spines, which make it difficult to fillet. Although the meat is sweet, with a flaky, tender texture, commercial fisheries have historically focussed on other, more economically viable species, such as the red drum. This could change, however. Although the sheepshead fish is relatively plentiful now, as stocks of red drum and other local fish decline, there are concerns that the toothy icon could be next.
In the meantime, don’t worry if you encounter one. Sheepshead fish don’t bite (unless you’re a clam or an oyster), but they do have a smile that would melt the heart of even the most indifferent orthodontist.
Read more:
- What is an axolotl? Everything you need to know about this charismatic amphibian
- What is a red-lipped batfish?
- What is a wolf eel?
- What is a warty comb jelly?
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