rhamphotheca:

To Sex-Starved Squid in the Dark, Either Gender Will Do

by Stephanie Pappas

Meeting girls is tough if you’re a male squid living in the deep, dark waters off the coast of California. You may run across your own species only rarely — and when you do, the deep-sea gloom makes it hard to tell whether your new pal is a guy or gal.

But one squid species has come up with a work-around to this matchmaking problem, a new study finds. The eight-armed lotharios simply mate with any squid of their species that crosses their path. If that means wasting some sperm on male-to-male matings, the squid don’t seem to mind.

This same-sex squid behavior can’t necessarily be taken as more evidence of homosexual bonding in the wild, according to study researcher Henk-Jan Hoving, a postdoctoral researcher at the Monterey Bay Aquarium Research Institute in Moss Landing, Calif. Rather, the squid seem to mate indiscriminately out of necessity…

(read more: Live Science)

rhamphotheca:

Snails Survive Being Eaten and Excreted by Birds

by Wynne Parry

Tiny snails can actually benefit from being eaten by birds, according to a new study that found about 15 percent of the snails eaten by two species of bird survived their journey through the birds’ guts and out the other end. The birds appear to spread the snails they have eaten via excrement, allowing the mollusks to travel much greater distances than they could crawling on their own, according to the researchers led by Shinichiro Wada of Tohoku University in Japan.

The researchers tested out their hypothesis by feeding 174 snails, a species called Tornatellides boeningi, to four omnivorous birds —three Japanese white-eyes and one brown-eared bulbul —that also prey upon them in the wild on the Japanese Ogasawara Islands. It took 30 to 40 minutes for the snails, all adults with shells about 0.1 inches (2.5 millimeters) high, to pass completely through the birds’ digestive systems…

(read more: Live Science)   (photo:  Shinichiro Wada)

rhamphotheca:

Creatures of the Deep Sea:  Vampire Squid

Vampire Squid (Vampyriteuthis infernalis) is an apt name for a creature that lurks in the lightless depths of the ocean (this animal is however a finned octopod, and not a true squid). Comfortable at 10,000 ft (3,000 m) below the surface, these diminutive cephalopods navigate the blackness with eyes that are proportionately the largest of any animal on Earth. The species gets its name from its dark, webbed arms, which it can draw over itself like a cloak.

(via: National Geo)   (photo: Kim Reisenbichler)

rhamphotheca:

Giant Octopus Eggs Hatch at the Vancouver Aquarium

It has been almost seven months since C.C., the giant Pacific octopus who lives at the Vancouver Aquarium, mated and laid eggs. Earlier this week, close to 300 of her eggs hatched. The babies are only 5 millimetres in length.

“Although it is not unusual for octopus eggs to hatch in aquariums, very few hatchings have ever survived,” explains Dr. Dennis Thoney, director of Animal Operations at the Vancouver Aquarium. “Chances of survival are very low because giant Pacific octopuses have a seven to ten month long pelagic larval stage. To further our knowledge of octopus reproduction, we will attempt to feed and maintain some the larvae for as long as possible.”

C.C. was introduced to her male partner, Clove, last October in the Strait of Georgia display. Mating marks the beginning of the end for octopuses, and Clove died 67 days after mating. C.C. is expected to die naturally in the coming weeks now that egg incubation is completed.

“Opportunities to observe giant Pacific octopus mating are rare and we have already been extremely lucky to witness it several times here at the Vancouver Aquarium,” adds Dr. Thoney. “There is much to learn about octopuses and we hope to learn more as we attempt to raise the newly hatched octopus larvae.”

The giant Pacific octopus typically lays around 70,000 eggs on average, of which only a few are expected to survive to adulthood in their natural habitat.

(via: Vancouver Aquarium)

intrinsicallylinkedlife:

Pfeffer’s Flamboyant Cuttlefish (Metasepia pfefferi) is a species of cuttlefish that lives in tropical Indo-Pacific waters off northern Australia, southern New Guinea, as well as numerous islands of the Philippines, Indonesia and Malaysia. This unique species of cuttlefish is poisonous.

intrinsicallylinkedlife:

Getting out of water we have the Roman snail.

The Roman snail (Helix pomatia), is a species of large, edible, air-breathing land snail. It is one of the most common species.

Most snails have thousands of microscopic tooth-like structures located on a ribbon-like tongue called a radula. The radula works like a file, ripping the food into small pieces.

Snails secrete mucus to keep their soft bodies from drying out. They also secrete mucus from the foot to aid in locomotion by reducing friction, and to help reduce the risk of mechanical injury from sharp objects, meaning they can crawl over a sharp edge like a straight razor and not be injured.

The snail’s main predator are ground beetles and ants.

iheartnudibranchs:

Chromodoris fidelis by Jurgen Koch

rhamphotheca:

Mysterious Ancient Creature Discovered (May 2010)

by Brett Israel

It’s not the mythical kraken, but an ancient creature belonging to the largest, nimblest and probably smartest group of invertebrates has jumped out of the fossil record with a different identity than previously thought. That finding restructures a branch on the evolutionary tree.

The tiny mysterious fossil of Nectocaris pteryx — previously described as a shrimp with a chordate tail — is neither a shrimp (an arthropod) nor a chordate (vertebrates and their nearest relatives), but a mollusk, according to a new study detailed in the May 27 issue of the journal Nature. 

Don’t picture boring mollusks, such as snails, slugs and mussels, however. Think cuttlefish, squid, and octopi — and yes, even the kraken — which are cephalopods, a member of the mollusk phylum. The 505 million-year-old creature is the oldest recorded cephalopod by about 10 to 15 million years and provides clues about modern cephalopod evolution…

(read more: Live Science)   (image: )

rhamphotheca:

Nectocaris pteryx is a species of possible cephalopod or arthropod affinity, known from the Middle Cambrian Burgess Shale. Nectocaris was a free-swimming, predatory or scavenging organism, possibly occupying a niche similar to the arrow worms.^[3]This lifestyle is honoured in its binomial name: Nectocaris means “swimming shrimp”… (read more: Wikipedia)

image:  Current reconstruction of Nectocaris, based on 92 specimens. Dorso-ventrally preserved specimens demonstrated that the fins were lateral, and the additional material indicated that the feature originally interpreted as an arthropod head-shield was in fact a nozzle-like appendage, which has been interpreted as a funnel. 

(image by  Citron)

archaeodiva:

Slimy and often sluggish they may be, but some molluscs deserve credit for their brains – which, it now appears, they managed to evolve independently, four times.

The mollusc family includes the most intelligent invertebrates on the planet: octopuses, squid and cuttlefish. Now, the latest and most sophisticated genetic analysis of their evolutionary history overturns our previous understanding of how they got so brainy.