Monterey Bay Aquarium
Monterey Bay Aquarium

9 Fascinating Facts About Cephalopods From Monterey Bay Aquarium

Monterey Bay Aquarium
Monterey Bay Aquarium

Cephalopods—the class of marine mollusks that includes octopus, squid, cuttlefish and nautiluses—are amazing animals unlike anything that walks on land. The world-renowned Monterey Bay Aquarium set out to shed new light on these incredible invertebrates with an expansive exhibit that opened this past April called Tentacles: The Astounding Lives of Octopuses, Squid and Cuttlefishes. Senior Aquarist Chris Payne took us on a walk-through of the 3700-square-foot exhibition to explain a little more about what makes these sea creatures so unique.

1. Although the differences between the species can be stark, they all have a basic body structure in common: A head with eyes, a mantle that contains all their internal organs, a siphon for scooting around the oceans that works by expelling a jet of water, and a powerful parrot-like beak with a file-like tongue called a radula. Additionally, they are most overtly identified by a "foot" that has evolved into either tentacles or arms—but those two appendages are not the same. Octopuses have eight arms, covered in hundreds of suckers, but no tentacles. Both squid and cuttlefishes have eight arms and then an additional two feeding tentacles that shoot out to grab prey and pull it in towards their arms. And nautiluses have up to a hundred tentacles, and no arms. For animals that have both, the distinction is how the appendages are used. "They use the feeding tentacles to attack their prey—shoot the two tentacles out, grab whatever it is they’re feeding on, pull the food into their arms, and then the arms will help manipulate the prey," Payne says.

2. They grow really fast. Most cephalopods only live for a year or two—even the giant pacific octopus has a maximum life span of just five years. (The exception, as always, is the nautilus, which is not even sexually mature until it's 15 years old.) Since they're born small, out of pearl-sized eggs, to reach their (admittedly variable) adult size, cephalopods exhibit an extremely fast growth rate.

3. To mate, the male cephalopod reaches into the female's mantle with one of his arms and deposits the sperm. But this doesn't necessarily mean the babies will be his. "Cephalopods can store the sperm and decide if they want to mate with one individual male or another individual male," Payne explains. Once mom has picked the perfect genes to pass on, she lays her eggs—usually 15 to 30 egg capsules with four to six embryos each.

4. And then she waits. During gestation, mom will guard the eggs and fan them to keep the embryos oxygenated. Her dedication to their safety is admirable and made significantly more so by the fact that during this time—which is typically several months but can sometimes span (at an extreme maximum) over four years—she does not eat at all. "They're expending as much energy as they can until the last egg and then that’s it. They die. There’s no round two," Payne says. He stipulates that, while this is typical, there are some species of squid and cuttlefish that can lay several clutches of eggs.

5. All cephalodpods used to have hard outer shells but only nautiluses retained them over the millennia. Without this physical shield, squids, octopuses, and cuttlefishes all developed ink sacks to serve as a defensive tactic. Since they are significantly slower than other cephalopods, nautiluses feed primarily on scraps, including shrimp and lobster molts, which provide the calcium they need to maintain their striking, striped, spiral shells.

6. The shells themselves are fascinating. They are an incredible natural example of a logarithmic spiral and give the nautilus the ability to regulate its buoyancy by taking in different amounts of water and gasses into the various chambers (the nautilus' mantle extends only partially into the shell).

7. All cephalopods, except (of course) nautilus, can change not only the color of their skin but also the texture. Sometimes this is a reaction to emotional stimulus—a flurry of cuttlefish turn black when they've been disturbed and the giant pacific octopus goes deep red when we open her tank, perhaps thinking we've brought food—but usually it's a matter of camouflage. Octopuses, in particular, spend most of their lives lying in wait to ambush potential prey, and to give themselves quite the competitive advantage, they alter their appearance to almost perfectly match the color and texture of their surroundings, from sandy ocean floors to rocky coral crevices.

8. The mimic octopus takes his shape-shifting a step further, transforming to resemble not just scenery but other animals as well. It's really better explained with a video:

9. Octopuses are certainly the smartest of the invertebrates (have you seen some of the cool things they've been caught on video doing?) but they are still an invertebrate and they put that lack of backbone to use. Their malleable bodies can fit through any space large enough to accommodate their beak.

All photos courtesy of Monterey Bay Aquarium.

IKEA Is Recalling Its New Dog Water Fountain Due to Suffocation Risk

In late 2017, IKEA released LURVIG, its first-ever line for pets, a collection that included beds, leashes, food bowls, and other staple products for dogs and cats. Unfortunately, one of those products is now being recalled over safety issues, according to Fast Company. If you own the LURVIG water dispenser, you should take it away from your pet immediately.

The automatic water fountain poses a suffocation hazard, the company announced in a recent statement. The retailer has received two reports of pets dying after getting their head stuck in it.

A water fountain for pets sits next to a bowl full of dog food.

The $8 water dispenser debuted in U.S. stores in October 2017 with the rest of its LURVIG line. Awkwardly enough, the product description included assurances of the product’s safety standards. It explained that “the LURVIG range was developed with the assistance of trained veterinarian Dr. Barbara Schäfer, who also works with product risk assessment at IKEA,” and went on to say that “the first thing to consider was safety: ‘Dogs will definitely chew on their toys and bring in dirt from their daily walks. Cats will definitely scratch on most surfaces and are sensitive to smell and texture. So safe, durable materials are very important.’”

It seems that smaller dogs are able to get their faces stuck in the dome-shaped plastic reservoir, which only appears to have one hole in it, at the bottom. As a result, dogs can suffocate if they can’t get out of it.

The product has been removed from IKEA’s website, and the retailer recommends that anyone who bought it stop using it and return it to the nearest IKEA store for a refund.

[h/t Fast Company]

10 Facts About the Portuguese Man O' War

Something a lot scarier than any Jersey Devil has been washing up on beaches in the Garden State lately: This month, the dangerous Portuguese Man O’ War—which has a potentially deadly sting—has been sighted in Cape May and Wildwood, New Jersey, which could lead to problems for beachgoers. Read on to learn more about these unusual creatures.


The Portuguese Man o’ War may look like a bloated jellyfish, but it’s actually a siphonophore—a bizarre group of animals that consist of colonies made up of dozens, hundreds, or even thousands of genetically-identical individual creatures. A siphonophore starts out as a fertilized egg. But as it develops, it starts "budding" into distinct structures and organisms. These tiny organisms—called polyps or zooids—can’t survive on their own, so they merge together into a tentacled mass. They must cooperate as one in order to do things like travel and catch food.

Though the zooids within a Man O’ War are basically clones, they come in different shapes and serve different purposes [PDF]. Dactylozooids are long hunting tentacles built to ensnare prey; gastrozooids are smaller tentacles which digest the food; and gonozooids are dangling entities whose job is to facilitate reproduction. Every Man O’ War also has a pneumatophore, or “float”—an overgrown, bag-like polyp which acts as a giant gas bladder and sits at the top of the colony. Capable of expanding or contracting at will, it provides the Man O’ War with some buoyancy control. An expanded float also enables the colony to harness winds to move around.


A view of a bluebottle under water.

When we say “Portuguese Man O’ War,” we’re talking about Physalia physalis, the bizarre siphonophore that’s scaring New Jerseyans right now. Also known as the Atlantic Portuguese Man O’ War, it can be found in warmer parts of the Pacific, the Caribbean, the Indian Ocean, and of course, the Atlantic.

Another kind of siphonophore which regularly stings beachgoers is the so-called bluebottle, Physalia utriculus. It’s sometimes called the Indo-Pacific “Portuguese” Man O’ War and is restricted to the Pacific and Indian Oceans. It’s smaller than the Atlantic species and unlike its bigger counterpart—which has multiple hunting tentacles—it hunts with a single, elongated tentacle.


In the age of sailing, many European navies used tall warships loaded with cannons and propelled by three masts. British sailors took to calling this kind of vessel a “Man of War.”

What does that have to do with Physalia physalias? These colonies spend a lot of time floating at the water’s surface, and when the gas bladder is expanded, it looks—and acts—a bit like a sailboat, hence the “Man O’ War.” As for the Portuguese part, 19th century scientists proposed that sailors encountered it near the Portuguese island of Madeira, while modern etymologists tend to think that it looked like the Portuguese version of the ship.

Or at least that’s one explanation for the creature’s peculiar name. It’s also been suggested that Renaissance-era sailors thought the pneumatophores resembled the helmets worn by Portugal’s soldiers during the 16th century.


Two Portuguese Man o' War washed up on the beach with their tentacles stretched out.

At least, that’s the maximum length for the dactylozooids—which are normally around 30 feet long and use venom-spewing cells to deliver painful, neurotoxic stings. When a tentacle is detached from the rest of the colony, it might wash ashore somewhere or drift around for days on end until it decomposes. Be warned: Even a severed tentacle can sting you.


The odds of being killed by a Portuguese Man O’ War are slim. But just because deaths are rare doesn't mean you should touch one: On February 11, 2018, 204 people in Hollywood, Florida were treated for stings, which can lead to red welts on the skin, muscle cramps, elevated heart rates, and vomiting.

Still, the creatures can kill: One unlucky victim suffered a full cardiovascular collapse and died after getting too close to a Man O’ War in eastern Florida back in 1987. More recently, a woman swimming off Sardinia was stung by one and died of what was believed to be anaphylactic shock.


Given that tiny fish make up about 70 to 90 percent of the Man O’ War’s diet (it also eats shrimp and other crustaceans), Nomeus gronovii, a.k.a. the Portuguese Man O’ War Fish, is playing a dangerous game: It lives among the siphonophore's tentacles even though it's not immune to its stings, swimming nimbly between the stingers. Young fish eat planktons which wander under their hosts and, as they get older, will sometimes steal the Man O’ War’s prey—or nibble on its tentacles.


The Man O’ War has a long list of enemies. Loggerhead sea turtles and the bizarre-looking ocean sunfish are thick-skinned enough to eat them. There are also “blue dragon” sea slugs, which not only devour the Man O’ War but actively harvest and appropriate its toxins. After storing Man O’ War stinging cells in their own skins, the blue dragons can use it as a predator deterrent.


A pink-tinted Portuguese Man O' War with blue tentacles in the surf at a beach.

Although it’s translucent, the float is usually tinted with blue, pink, and/or purple hues. Beaches along the American Gulf Coast raise purple flags in order to let visitors know when groups of Man O’ War (or other potentially deadly sea creatures) are at large.


The Man O' War's gonozooids have sacs that house ovaries or testes—so each colony can therefore be considered “male” or “female.” Though marine biologists aren’t completely sure how the Man O’ War procreates, one theory is that the gonozooids release eggs and sperm into the open ocean, which become fertilized when they cross paths with floating eggs or sperm from other Man O’ War colonies. This “broadcast spawning” method of reproduction is also used by many species of coral, fan worms, sea anemone, and jellyfish.


The Man O’ War isn't always seen in isolation. Legions consisting of over 1000 colonies have been observed floating around together. Because they drift along on (somewhat) predictable winds and ocean currents, it’s possible to anticipate where and when a lot of the creatures will show up. For example, the Gulf Coast’s Man O’ War season arrives in the winter months.


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