Pictured above is a starburst anemone (Anthopleura sola) with fully inflated acrorhagi (the tentacles with the rounded white ends). When tidepooling in the “Low Tide” Zone, the starburst anemone is often discovered in the middle of a fight with another anemone, with its white, blunt acrorhagi inflated. As anemones fight, touching each other with their acrorhagi, the white areas of the acrorhagi become tattered. The white is a concentration of stinging cells and when touched it will slough off, to keep on stinging the enemy again and again. Eventually one anemone will move away from its neighbor in order to stop the fight.
The difference between a colossal squid and a giant squid
(left: giant squid middle and right: colossal squid)
Colossal squid (Mesonychoteuthis hamiltoni) are slightly shorter than giant squid (Architeuthis dux), but have a larger, heavier body. Te Papa’s colossal squid tips the scales at a massive 490 kg. In contrast, giant squid weigh up to about 275 kg.
All squid have sharp horny beaks made of material similar to human fingernails. The colossal squid has the largest beak of any squid, including the giant squid. The tips of the colossal squid’s tentacles (the clubs) are armed with two unusual rows of sharp, swivelling hooks, and two rows of tiny suckers. Other squid species also have tentacle hooks. The beak and the hooks are lethal weapons for catching and holding large fish like the toothfish.
The Portuguese Man O’ War is a remarkable colonial organism, made up of various highly specialized organisms called zooids. Aaron Ansarov’s photographs capture the structures of these zooids and then mirror them, creating strange psychedelic images of these creatures.
This juvenile fish has developing bone stained red and developing cartilage stained blue.
Mark Currey, PLoS Genetics, doi:10.1371/image.pgen.v06.i02.g001
Seahorses get their exceptional flexibility from the structure of their bony plates, which form its external armor. The plates slide past each other as the creature moves. Shown at left is an image from a micro CT-scan of the animal, revealing the seahorse’s skeleton, as well as its bony plates. The structure, lightness and strength of many materials in nature are inspiring scientists and engineers to create new “bio-mimetic” materials that could lead to better body armor, lighter aircraft and stronger, more flexible materials.
A huddle of starfish adds a splash of color to the Olympic Coast National Marine Sanctuary in Washington State. The Sanctuary protects 2,408 square nautical miles off the coast, the size of Delaware and Rhode Island combined. Living in this protected area are organisms ranging from microscopic plankton to sea otters to albatross to migrating gray whales. It’s a high-nutrient environment, which is why intertidal species like these starfish thrive.
Sharksuckers use the spines and suction of their sucking disc to attach themselves to large marine animals. They don’t seem to cause any harm, or benefit, to the animal they’re attached to, and they live off scraps of food, faeces or parasites from the larger animal. Some people are known to use sharksuckers to catch other fish, throwing them into the sea attached to a fishing line and pulling them in once they are attached to a larger sea animal.
According to a new study conducted by ichthyologists Dr Ralf Britz of the Natural History Museum and Dr David Johnson of the Smithsonian National Museum of Natural History, the skeleton of the sharksucker fish’s disc is formed in development through the expansion of both the bases of the dorsal fin spines and the distal radial elements of the fin supports.