Pyrosomes: The Ultimate Social Networkers

pyrosome

This pyrosome is made up of thousands of tiny organisms linked together as one. (Photo credit: Mark Conlin/Alamy)

If you’re looking for a strange sea creature, you can’t get much weirder than the giant pyrosome. With an appearance like a monster out of a science fiction movie, those who’ve had the good luck to see them have likened them to everything from unicorns, due to their rareness, to the Borg, because of how they stick together and seem to be part of a collective.

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Say Hello to the Sarcastic Fringehead

sarcastic fringehead

The sarcastic fringehead lives in the nooks and crannies found within the rocky ocean bottom. (Photo credit: Ralph A. Clevenger/Corbis)

The sarcastic fringehead (Neoclinus blanchardi) gets its name from both its temperament and the fringelike appendages that are found atop its head. Despite its humorous name, this fish’s behavior is no joke. When approached by potential predators or fellow fringeheads seeking new territory, this fish aggressively defends its space.

In addition to its fringe-topped head, this fish’s appearance is also marked by a long and slender body that is typically brown-gray to black in color. Most fringeheads are between 8 and 29 centimeters (3-8 inches) in length. The fish’s large head features wide jaws and needle-like sharp teeth. These features play an important role in the fish’s territorial behavior.

Fringeheads feed on small crustaceans such as crabs and shrimp. Because their territory is so small, they must aggressively defend it in order to ensure they have enough food to eat. These fish are ambush predators, meaning they lie in wait for potential prey to swim by. When they do, the fringeheads are ready to pounce, thus catching their prey by surprise.

When its territory is invaded, the sarcastic fringehead launches into its threat display. This display includes flexing its body and head, spreading its gill covers, and snapping its jaws. If this behavior doesn’t deter a potential competitor, the fringehead opts for a little mouth-wresting (see the video link below to watch this behavior in action). Because the fringehead has poor eyesight, the mouth-wrestling activity allows the fish to determine the size of its competitor. The larger-sized fish is typically the winner when it comes to wrestling by mouth.

This fierce fish lives in the waters of the San Francisco Bay south to the Cedros Island in Baja California, Mexico. It typically inhabits waters at depths between 3 and 73 meters. Its particular territory is often quite small, and limited to a crack within a rock, an abandoned clam or snail shell, or even human trash that makes its way to the bottom of the sea, such as a can or bottle. In fact, there’s a portion of the ocean bottom in southern California’s Redondo Canyon that is covered with litter. Nearly every bottle, can, or similarly-shaped container is home to a sarcastic fringehead.

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Species Information: Sarcastic Fringehead
Amazing Animals: Sarcastic Fringehead (video)
Species Overview: Sarcastic Fringehead
Meet the Sarcastic Fringehead

The Mantis Shrimp: An Unusual Underwater Inhabitant

There are more than 350 species of mantis shrimp. (Photo credit: SuperStock/Alamy)

The mantis shrimp is neither a mantis nor a shrimp, but it got its name due to its resemblance to both of these creatures. The mantis shrimp is actually a marine crustacean that belongs to the order Stomatopoda. These unusual marine dwellers separated from other crustacean groups about 400 million years ago. Currently, scientists have identified over 350 different species of mantis shrimp. These shrimp are primarily found in tropical and subtropical waters, though some live in temperate ocean habitats.

There are two main types of mantis shrimps. The two types are distinguished by the appearance of their raptorial appendages, or raps. Spearers have sharp barbs on the tip of their rap, which they use to spear soft-bodied prey, such as shrimp or fish. Smashers have a club-like modification on their raptorial appendage, which lets them smash their shelled prey, such as clams and snails. Perhaps what makes the smashers club-like weapon most formidable is the speed at which it can be deployed. Scientists using super-high speed video cameras were able to calculate the speed at which a smasher mantis shrimp strikes its prey. So how fast is a mantis shrimp’s punch? At a speed of nearly 80 kilometers per hour (50 mph), a strike from a mantis shrimp counts as one of the fastest limb movements in the entire animal kingdom.

But their raptorial appendage weaponry is not the only strange thing about mantis shrimp. Mantis shrimp eyesight is also quite unusual. To begin with, their eyes are able to distinguish between 100,000 different colors–that is 10 times the amount that human eyes perceive. Why might mantis shrimp have the ability to perceive such a wide range of wavelengths? It turns out that a number of mantis shrimp species have fluorescent yellow markings on the scales of their antennae and carapace. Research published in January 2004 in the journal Science indicates that the fluorescent markings are part of a threat display directed toward males of the same species as well as potential predators.

A mantis shrimp’s eyes can perceive 10 times as many colors as a human. (Photo credit: Michael Patrick O’Neill/Photo Researchers, Inc.)

The ability to perceive such a wide range of light wavelengths isn’t the only thing that makes a mantis shrimp’s eyes interesting. A mantis shrimp’s eyes are also able to perceive circular polarized light, or CPL, something no other animal can do. Though humans cannot perceive this type of light, we use CPL filters in items such as camera lenses and 3D glasses.

According to research published in March 2008 in the journal Current Biology, one benefit of circular polarization vision is that it enhances contrast in murky conditions, such as the turbid waters that mantis shrimp inhabit, which lets the shrimp see better in their surroundings. In addition, research indicates that the males of some species of mantis shrimp have a patch on their bodies that reflects circular polarized light. Scientists hypothesize that these reflective patches may be used as a part of a sex-specific secret communication channel between mantis shrimp, since other marine animals cannot perceive CPL.

Recent research published in August 2011 in the journal Aquatic Biology indicates that mantis shrimp also communicate by rumbling. Vibrations within the mantis shrimps muscles are responsible for these low-frequency noises. Recordings made near the animals muddy underwater burrows indicate that the mantis shrimp use these noises as a way to establish and maintain territories. Since only males were observed making these noises, scientists think that the rumbling may also be used to attract female mates.

Though these strange underwater creatures have been around for 400 million years, much remains unknown about them, particularly since they spend most of their time in their undersea burrows. Many mantis shrimp species are also nocturnal, which makes tracking their behavior that much more difficult. However, from the data and observations that researchers have been able to gather thus far about mantis shrimp behavior and body composition, it seems these strange marine crustaceans are definitely worth the extra effort required to study them.

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An Unusual Fish that Lives Deep in the Ocean

Deep sea anglerfish use a bioluminescent lure to capture prey. (Photo credit: Peter David/Taxi/Getty Images)

The female deep sea anglerfish uses a bioluminescent lure that dangles over her head to attract prey. However, her lure isn’t just used to capture food to eat. Male anglerfish use the females light source to make sure shes a member of the same species before he latches onto her as a lifelong mate.

There are more than 200 species of anglerfish that live within the Atlantic and Arctic oceans. Though many live at depths of nearly 1000 meters beneath the oceans surface, a few species inhabit the shallow waters of tropical habitats.

Female and male anglerfish look quite different from one another. Only females have a lure above their heads. The lure is actually a portion of the females dorsal spine which glows a blue-green color due to the presence of bioluminescent bacteria. Because their rounded shape makes them poor swimmers, an anglerfish typically lies in wait for its prey, waving the lure back and forth slowly. In addition to its unusual headgear, the female also features a ferocious mouthful of sharp teeth that angle inward, which helps prevent prey from escaping once the food is in its mouth. The fish are also able to open their jaws wide enough to swallow prey twice their size, allowing them to make the most of each meal.

In comparison to females, male anglerfish are much smaller in size. In fact, one male anglerfish specimen holds the title as the worlds smallest vertebrate, measuring in at just 6.2 millimeters in length. As the male anglerfish matures, its digestive system begins to deteriorate, rendering it basically unable to get the nutrients it needs to live. To survive, the male anglerfish must find a mate. A pair of nostrils and a set of large eyes dominate a male anglerfishs face. It uses its nostrils to sniff out the scent of pheromones that announce the presence of nearby female anglerfish. It uses its large eyes to ensure that the anglerfish it sees is a member of the same species. Once it has found a mate, the male latches onto the females back, belly, or side by biting it with its own set of sharp teeth. Its at this point that things get really interesting.

This female anglerfish has two males attached to its body. (Photo credit: Darlyne A. Murawski/Peter Arnold, Inc./Alamy)

Once the male bites the female, the male releases enzymes that cause its mouth to dissolve along with the females skin, which fuses the two together. Over time their bloodstream becomes one, and the male loses his eyes along with all other internal organs except for its testes. The female is now for all intents and purposes a hermaphrodite, meaning it can self-fertilize. A female may have more than six males on its body at one time. However, some females live their entire lives–which may span between 25 and 30 years–without ever encountering a male.

When the female is ready to reproduce, it lays eggs in a huge swath one meter wide by nine meters long. This sheet of eggs floats freely in the oceans waters. Larvae hatch from the eggs and feed on plankton at the waters surface before returning to the oceans depths as they mature, beginning their unusual deep-sea life cycle once again.

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A Whale of a Tale

Humpback whales migrate seasonally from their feeding grounds to their breeding grounds. (Photo credit: NOAA)

People typically use Flickr to upload photos to share images of people, places, and events with their friends and family. A recent upload led to an amazing scientific discovery–a photo of a humpback whales fluke, or tail, taken during a whale sightseeing cruise 10 years earlier placed a humpback whale 9,800 km (6,000 miles) from where it had first been sighted by research scientists–a figure 3,200 km (2,000 miles) beyond the average whales yearly migration.

Marian C. Neves, a whale researcher associated with Brazil’s Instituto Baleia Jubarte, first spotted this particular humpback whale on August 7, 1999 off the coast of Brazil. At that time, scientists took skin samples from the whale and genetic analyses of the samples indicated that the whale, identified as whale 1363, was a female. On September 21, 2001, Freddy Johansen, a tourist from Norway, photographed the fluke of the same whale during a whale sightseeing cruise off the east coast of Madagascar. He didn’t upload the images from his trip until 2009, when he decided to back up photographs from his trip and share them with friends.

Gale McCullough, a research associate with Allied Whale, the College of the Atlantic’s marine mammal research group, works as a liaison with Flickr and searches the site for humpback whale images. She was the first to discover Johansen’s whale fluke photograph and identify it as a possible match to whale 1363. Each humpback whale fluke has a distinct pattern of speckles, and can be used to identify individual humpback whales, in the same way that fingerprints can be used to identify individual humans.

The uniqueness of whale fluke patterns was first discovered by College of the Atlantic researchers in the 1970s and quickly revolutionized the way scientists tracked and identified individual whales. For over 30 years, scientists have placed the data they have gathered (including identifying traits such as tail shape and color and underside patterns) on individual humpback whales into the Antarctic Humpback Whale Catalogue. Scientists across the world use this catalogue to study humpback whales and gather data on population sizes, migration patterns, sexual maturity, and behavior patterns.

Each humpback whale can be identified by its fluke, or tail, which has a unique shape and color pattern. (Photo credit: J. Waite, OAR/National Undersea Research Program (NURP); National Marine Mammal Lab/NOAA)

Each humpback whale can be identified by its fluke, or tail, which has a unique shape and color pattern. (Photo credit: J. Waite, OAR/National Undersea Research Program (NURP); National Marine Mammal Lab/NOAA)

Most humpback whales migrate twice-yearly. They spend their summers in temperate or polar waters where they feed on krill and then spend their winters in tropical waters where they mate and the females give birth to their calves. The whales follow the same route, which averages around 6,400 km (4,000 miles), year after year. What makes the distance traveled by whale 1363 extra unusual was that she was identified at two different breeding grounds.

Peter T. Stevick, lead author on a paper published about the humpback whale in the journal Biology Letters, offers two possible explanations for its wayward journey. One possible explanation is that the whale was exploring new habitat. A second explanation is that the whale simply got lost. For example, it might have gotten off course while tracking prey or looking for new feeding sites.

According to the Biology Letters article, the shortest possible distance between Brazil and Madagascar (with a route taking the whale from the South Atlantic Ocean to Africa and around to Madagascar in the Indian Ocean) is 9,800 km, which is 4,000 km longer than any previously-recorded movement between breeding grounds for a humpback whale. This distance is twice the species typical seasonal migratory distance and is the longest documented movement by a mammal.

Movement of an individual between breeding areas separated by approximately 90 longitudinal degrees, a continent, an ocean basin and nearly 10,000 km illustrates the ability of humpback whales to range across large portions of the globe, the authors explain in the article. Whatever factors resulted in this rare event, such extensive movement by an individual of a species that is typically philopatric [that is, returns to its place of birth] shows the extent of behavioral flexibility in movement that may be demonstrated within a species.

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