10 Weird Facts About Lobsters

Lobsters were considered a delicacy during the Middle Ages in Europe, and even served as medicine. The rostrum, or frontal part of the body, was pulverized and used to help people pass kidney stones. The gastrolith, or gizzard stone which the lobster uses to help grind up food, was handy for treating stomach aches [source: Lobster Conservancy].

Fast-forward a few hundred years and attitudes changed drastically. Lobster was so abundant in 18th and early-19thcentury New England that it was fed to pigs and the shells used as fertilizer. Indentured servants in Massachusetts were so sick of eating it that they won a court case to keep their masters from feeding them lobster more than three times a week [source: Dembosky].

The first shift to luxury food item took place in the late 1800s, as wealthy city-dwellers flocked to the beach and enjoyed the novel taste (for them) of lobster. Advances in refrigeration allowed live ones to be transported all over the country. As demand increased, supply decreased, which drove up the price. Supply and demand has ebbed and flowed over the years, but these days lobster is considered fancy food.

In the wild, most lobsters are a mottled greenish brown. They turn red when cooked because heating breaks the bond between pigmentation and protein in the shell. The red color comes from the expression of astaxanthin, a type of carotenoid pigment found in orange-colored plants, eaten by the animals the lobster eats [source: Cowan].

A small number of lobsters can be red prior to being cooked -- as well as orange, yellow, green, blue and various combinations of these colors. In some cases, these hues are a genetic mutation. Other times, it has to do with the food the lobster eats; if it only has one type of food available, it may turn a solid color as a result [source: Cowan].

So far, we've been referring to the American lobster. This big-clawed crustacean is found off the east coast of Canada and the United States. Its cousin, the European lobster, has smaller claws and its natural coloring is dark blue with spots and a yellow underbelly. It'd found in the waters around Western Europe and North Africa. Non-clawed lobsters, called rock lobsters or spiny lobsters, are found in warmer waters around the world and come in a variety of colors [sources: Gulf of Maine Research Institute, St. Lawrence Global Observatory].

You might look a little differently at the next lobster you see when you learn how they excrete their waste. Good thing we don't eat their faces, right? A lobster pees from openings (nephrophores) located at the base of its second antennae. These excretory organs are called green glands and include a sac linked to a bladder by a coiled tube [source: Lobster Conservancy].

Lobsters also excrete from other places on their bodies, including their gills and digestive glands. Excreting from the nephrophores isn't just about getting rid of toxic waste products, though -- it's part of the lobster mating ritual.

Male lobsters love to fight. Female lobsters seek out the most aggressive, dominant male in the area and show their interest by peeing repeatedly into his shelter. Their urine contains pheromones, which calm him down and get him in the mood, so to speak. Lobsters also urinate in each others' faces during fights to express themselves [source: Markey].

Just in case peeing from their faces isn't unusual enough for you, lobsters have some other unique anatomical characteristics. A lobster's eyes at the base of its antennae detect light and shadows, but not colors or images -- most of its seeing is done with its three pairs of antennae. The large pair is used for feeling around and the smaller two pairs help it navigate via smell [source: Lobster Conservancy]. An appendage between its eyes called a rostrum often gets mistaken for a nose, but it's just there to protect the eyes during fights.

And that's not all. Lobsters have two stomachs. One is located in what we'd consider the lobster's head -- right behind its eyes. This stomach contains teeth-like features (called a gastric mill) that are used to crush the lobster's food. Once the food is fine enough, it passes to the other stomach. Most of a lobster's abdomen is taken up by a digestive gland that serves as the filtration system -- sort of like your liver. Called the tomalley, it turns green when cooked, and some consider it a delicacy [source: Lobster Conservancy].

Clawed lobsters typically have two differently-sized pincers. The larger of the two is the crusher, and it's used for -- you guessed it -- crushing through the shells and carapaces of its prey. The smaller of the two claws, the cutter or seizer, grabs onto meat and shreds it into smaller pieces so that the smallest antennae can carry it into the lobster's mouth.

Lobsters tend to have a dominant claw -- meaning that they are either right-clawed or left-clawed -- and their crusher claw can be on either side. Juvenile lobsters start out with two cutters, and one develops into a crusher over time as the lobster locates objects to pick up. Scientists have been able to induce lobsters to avoid developing a crusher claw, but not to generate two crushers -- those have only been seen in the wild [source: Cowan].

No matter which claw is dominant, the lobster isn't all that attached to it -- literally. If a lobster loses a claw or leg, it will grow another when molting. Molting happens several times a year until the lobster is a full-sized adult. During molting the carapace splits and every hard piece is shed. Any missing limbs regrow during this time, and are identical to the original. A lobster can also drop a limb or claw if necessary to save its life, such as to get away from a predator. This adaptive phenomenon is called autotomy or reflex amputation [sources: McCarthy, NOAA Fisheries Service].

Some people avoid cooking lobster at home because of the way that they're normally dispatched -- headfirst, live, into a pot of boiling water. Some home cooks have been horrified by sounds coming from the inside of the pot -- noises, which they believe, are the lobster screaming in pain as it dies. The thing is, lobster don't have vocal cords or any way of making noise. The sounds heard are probably air escaping from the lobster's shell. There may be a crackling noise from live lobsters as they rub their legs, together, but that's about it.

So if they're not screaming, do they feel pain at all? That's a matter of some debate. Some researchers claim that they don't because they lack a complex nervous system or brain like vertebrates do. A 2005 study by the Norwegian Scientific Committee for Food Safety concluded that any violent reaction by the lobster to being cooked is a reflexive response to an unpleasant stimuli, called nociception -- not the same thing as pain and suffering. But a 2013 study conducted at Queen's University Belfast in the U.K. had the opposite conclusion [source: Cressey]. The jury's still out, so if you love to eat lobster but want to know it's being prepared in the most humane way possible, seek out restaurants that use a CrustaStun, a machine that quickly kills lobster and other crustaceans via electrocution.

In a 1996 episode of the sitcom "Friends," the character Phoebe compared Ross and Rachel's turbulent romance to those of lobsters, stating, "It's a known fact that lobsters fall in love and mate for life." There are earlier examples of this theory as well, but it's simply not true. As we mentioned before, a female lobster visits the most dominant male in the neighborhood and entices him into mating by peeing in his shelter. After several visits, the male gets the message and lobster love ensues. First the female has to disrobe, err, molt. After the deed is done, she hangs around until her shell has re-grown, then takes off. The whole rendezvous takes between 10 days and two weeks [source: Markey].

But then another female comes by and does the same thing. And another... and another ... until all the female lobsters around have mated with the dominant male lobster. So instead of mating for life, lobsters are serial monogamists, having one exclusive, but very short-term, relationship after another [source: Markey]. If you're a fan of "Friends" you know that Ross and Rachel did eventually end up together -- after 10 seasons and numerous other relationships.

When lobsters mate, the male deposits his sperm into the female before she leaves, but that doesn't mean that her eggs are fertilized right away. In some cases he hasn't provided enough sperm to fertilize all of her eggs -- there could be tens of thousands of them -- so she may seek out one or more additional males to get the job done [source: Gosselin]. But even then her eggs might not be fertilized, because the female decides when conditions are just right. She may store live sperm in her body for two years before using them to fertilize her eggs [source: NOAA Fisheries Service].

Once the lobster fertilizes the eggs, they may stay inside her for another year before she lays them. And then they can stay attached to her swimmerets -- the small legs under her tail -- for another 9 to 11 months [source: Cowan].

After they hatch, the larvae float for about a month before settling on the bottom of the ocean to grow. Only 1 percent of larvae make it to the bottom and in general, just two of every 50,000 eggs live long enough to become adult lobsters of catchable size [source: NOAA Fisheries Service]. The lengthy life cycle and small payoff help explain why female lobsters are discriminating about when they decide to fertilize and lay their eggs.

One reason why more baby lobsters don't make it to adulthood? They tend to turn on each other. After hatching, lobsters go through numerous stages of development. Once they start to actually look like little lobsters, they're not just floating along and eating zooplankton, fish eggs and other types of larvae anymore. They're competing for food and going after prey like crab, gastropods, starfish and marine worms [source: St. Lawrence Global Observatory]. In close quarters, these juveniles will eat each other without any qualms. This behavior is part of why lobsters aren't often raised in captivity -- they have to be separated into individual containers [source: Anderson].

This cannibalistic behavior isn't limited to baby lobsters, though. It's common for adults to eat juveniles or lobsters that have just molted when they're in traps or tanks. Until recently, though, researchers hadn't witnessed this type of behavior in the wild. Then in 2012, scientists in Maine filmed lobsters practicing infanticide. They tethered a juvenile lobster, figuring that its natural predators, such as cod and skate, would take advantage. At night, though, adult lobsters fought over it. The cannibalism was blamed on a recent glut of lobsters. Warmer waters and overfishing practices had reduced the populations of their natural predators [source: Doucleff].

If you believe everything you read, you may recall seeing a lobster meme in the summer of 2013 -- a photo of a lobster with the phrase "biologically immortal, delicious with butter." I can attest to the latter part, but the former isn't true. Lobsters don't age in the same way as most other animals – they don't get weaker or lose their ability to reproduce, and will keep on molting and growing. However, that doesn't mean that they live forever. At some point, even if they aren't caught, they die due to natural causes. Often this is because they run out of energy to molt at all and not molting leads to fatal diseases [source: Koren].

So, we know that lobsters eventually die, but we aren't quite sure when. Lobsters reach their adult size when they weigh between 1.5 and 2 pounds (680 and 907 grams), but the heaviest one ever caught clocked in at 44 pounds (20 kilograms) [source: BBC]. Some estimate that lobsters in the wild can live up to 50 years.

Scientists estimate a lobster's age by measuring levels of materials known to accumulate in its body over time, such as deposits of fat in its eyestalks or a pigment called eurolipofuscin in its brain [source: Koren]. The latest research indicates that the best way to estimate lobster age may be by counting age bands well hidden inside the gastric mill in one of its stomachs [source: Poppick].