Needlefish are not dangerous because they are aggressive, venomous or poisonous, or pack a mean bite. They're dangerous mostly because of their shape, their needle-like teeth, and their ability to become airborne. The dagger-shaped fish usually swim just a few inches below the water's surface, but they can launch themselves out of the water at speeds of up to 37 miles per hour. They have been known to cause injury and sometimes death in people who happen to be in their way.
Oysters ultimately rely on the carbon present in water as raw materials from which they create their shells. The way these shells are generally made is that these organisms pick up calcium, they package it in proteins and then then direct these proteins to their exterior. Once there, these proteins release calcium in the presence of carbonate ions, and then slowly secrete these building blocks, gradually forming a shell that is made up of 90%+ calcium carbonate, some organic material, and trace amounts of other elements such as iron and manganese.
The mola's odd shape disguises its true claim to fame: it's the heaviest bony fish in the world. Yes, yes, I know that whale sharks are really big, and they aren't whales, they're fish. But they're not bony fish — the skeletons of sharks and rays are made from cartilage. So when you look at all the other non-elasmobranch fishes out there, molas take the prize for size.
Hellbenders or (snot otters) hunt like eels, lurking under heavy rocks and lunging at crayfish, worms, and small fish. And their gullet is enormous — they can swallow fish almost as long as themselves.
Clashing colonies of sea anemones fight as organized armies with distinct castes of warriors, scouts, reproductives and other types, according to a new study. The sea anemone Anthopleura elegantissima lives in large colonies of genetically identical clones on boulders around the tide line. Where two colonies meet they form a distinct boundary zone. Anemones that contact an animal from another colony will fight, hitting each other with special tentacles that leave patches of stinging cells stuck to their opponent.
Batfish are not good swimmers; they use their highly adapted pectoral, pelvic and anal fins to "walk" on the ocean floor. When the batfish reaches maturity, its dorsal fin becomes a single spine-like projection (thought to function primarily as a lure for prey).
The giant Amazon leech (Haementeria ghilianii) can grow up to 18 inches and live up to 20 years. And yes, this one's a blood-feeder. Like all hematophagous species, H. ghilianii sticks its proboscis (which can be up to 6 inches long) into a host, drinks its fill, and falls off. Scientists thought the species was extinct until a zoologist found two specimens in the 1970s, one of whom he named Grandma Moses.
A shark's rare "virgin birth" in an Italian aquarium may be the first of its kind, scientists say. The female baby smoothhound shark (Mustelus mustelus) — known as Ispera, or "hope" in Maltese — was recently born at the Cala Gonone Aquarium in Sardinia to a mother that has spent the past decade sharing a tank with one other female and no males, this rare phenomenon, known as parthenogenesis, is the result of females' ability to self-fertilize their own eggs in extreme scenarios. Parthenogenesis has been observed in more than 80 vertebrate species — including sharks, fish and reptiles — but this may be the first documented occurrence in a smoothhound shark.
A team led by Egyptian scientists have dug up a 43 million-year-old fossil in the Sahara Desert in Egypt of a now-extinct amphibious four-legged whale. The authors of the study say that this creature had "unique features of the skull" and that its "mandible suggest a capacity for more efficient oral mechanical processing ." The new whale is called Phiomicetus anubis, which the scientists named in part after Anubis, the canine-headed Egyptian god associated with mummification and the afterlife. It was likely a top predator at the time, similar to what a killer whale is today
Discovered in 1986, Sacabambaspis was a jawless fish that inhabited coastal areas of a shallow sea that once extended across parts of North America. The fish had a broad head-shield and a body that narrowed to end in a small fin. It was a bottom-feeder, and would suck in scraps of food through its ever-open mouth. Sacabambaspis had sense organs that helped it to feel movement in the water, allowing it to judge the distance to its prey and predators. Scientist believe it was a poor swimmer because it lacked paired fins.