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This giant eyeball from a mysterious sea creature washed ashore and was found by a man walking the beach in Pompano Beach, Florida, on October 10, 2012. The eyeball was later sent to the Florida Fish and Wildlife Research Institute in St. Petersburg, and was identified as coming from a swordfish, likely cut by a fisherman and tossed into the sea.

(via: The Atlantic)

(photo: AP / Florida Fish & Wildlife Conserv. Comm., Carli Segelson)

rhamphotheca:

The Paleo-Diet: Dinosaurs Lose Weight in New Study

by Charles Choi

The fact that bones have curves has now thrown a curveball into calculations of dinosaur weight, researchers say.

New estimates suggest dinosaurs may have been lighter than once thought, scientists explain.

With the rare exceptions of fossilized scraps of skin, feathers, bristles and other relatively soft tissues, all that remains of most extinct creatures are their skeletons. One way that investigators seek to learn more about these lost animals is to deduce their weight from their bones.

Traditionally, researchers would calculate estimates of dinosaur mass using a leg measurement such as the circumference of leg bones, understanding the relationship between body mass and this circumference in modern animals, “and scaling this up to the size of a dinosaur,” said researcher Charlotte Brassey, a biomechanist at the University of Manchester in England…

(read more: Live Science)             

(images: T - Bill Sellers; B - Charlotte Brassey)

rhamphotheca:

Secrets of Sticky Gecko Feet Revealed

by Ella Davies

Sure-footed lizards and beetles keep their feet dry to secure their grip, according to scientists. Previous studies have attributed both species’ remarkable ‘sticking power’ to microscopic hairs on their feet. These hairs are attracted to surfaces by the forces between molecules, creating a strong footing. Two studies now suggest that the animals ‘walk on air’ to overcome wet surfaces, trapping bubbles between these tiny hairs.

Researchers from the University of Akron, Ohio, US, put tokay geckos through their paces in the lab. Their results are published in the Journal of Experimental Biology.

To test the tropical geckos’ powers of adhesion when dry, the team lowered them onto a sheet of glass. Once a strong bond had been made scientists gently pulled the harnessed lizard away from the glass using a small motor. The steadfast reptiles only became unstuck at forces around 20 times their own body weight. But when water was introduced to the environment, their sticking power was really put to the test…

(read more: BBC Nature)

rhamphotheca:

Metamorphosis: Changing Bodies, but Not Personalities

by Chelsea Wald

Some of our personality traits from childhood stick with us for the rest of our lives. An early shyness on the playground doesn’t always go away in the boardroom, for example. But what if your entire body changed as you aged, transforming you into a completely unrecognizable creature? Would you retain the personality of your youth? A new study in frogs suggests that you would.

In the past decade, scientists have shown that a broad range of animals—from dogs to sea anemones—display consistent personalities throughout their lives. Despite changes in their environment, individuals maintain their tendencies, such as being more or less active and exploratory, relative to other individuals of their species. But some researchers have theorized that animals that undergo metamorphosis should be exceptions.

The full-body transformation, seen in everything from frogs to butterflies, dramatically alters every aspect of the animal—not only its shape, but also where it lives and what it needs to do to survive and reproduce. Why, then, shouldn’t metamorphosis also change the animal’s personality, so that strengths in larvae don’t become flaws in adults? The relative restlessness that helps a caterpillar find food better than its peers, for instance, could get the butterfly into trouble with predators…

(read more: Science NOW)       (image: Christian Fischer/Wikipedia)

rhamphotheca:

How sticky toepads evolved in geckos and what that means for adhesive technologies

by PhysOrg staff

Geckos have independently evolved their trademark sticky feet as many as 11 times, and lost them nine times, according to research published June 27 in the open access journal PLoS ONE.

Geckos are known for sticky toes that allow them to climb up walls and even hang upside down on ceilings. A new study shows that geckos have gained and lost these unique adhesive structures multiple times over the course of their long evolutionary history in response to habitat changes.

“Scientists have long thought that adhesive toepads originated just once in geckos, twice at the most,” says University of Minnesota postdoctoral researcher Tony Gamble, a coauthor of the study. “To discover that geckos evolved sticky toepads again and again is amazing.”

Geckos, a type of lizard, are found in tropical and semitropical regions around the world. About 60 percent of the approximately 1,400 gecko species have adhesive toepads. Remaining species lack the pads and are unable to climb smooth surfaces. Geckos with these toepads are able to exploit vertical habitats on rocks and boulders that many other kinds of lizards can’t easily get to. This advantage gives them access to food in these environments, such as moths and spiders. Climbing also helps geckos avoid predators…

(read more: PhysOrg)        

(images: Four gecko species along with their feet showing diversity of adhesive toepad types. top to bttm Ptyodactylus guttatusHemidactylus frenatus, Phelsuma laticauda, and Sphaerodactylus elegans)

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More information: Gamble T, Greenbaum E, Jackman TR, Russell AP, Bauer AM (2012) Repeated Origin and Loss of Adhesive Toepads in GeckosPLoS ONE 7(6): e39429.doi:10.1371/journal.pone.0039429

Journal reference: PLoS ONE

Provided by Villanova University

rhamphotheca:

Dragonfishes, Unraveling a Skelatal Mystery

By Stephanie Guzik

An international team of scientists including Nalani Schnell (Germany), Ralf Britz (England), and Smithsonian ichthyologist Dave Johnson, has been awarded the Reinhard Rieger Award for excellence in research in zoomorphology for their 2010 publication in the Journal of Morphology, New Insights into the Complex Structure and Ontogeny of the Occipito-Vertebral Gap in Barbeled Dragonfishes (Stomiidae, Teleostei).

Barbeled dragonfishes are members of the deep-sea Family Stomiidae. There are 27 genera (groups) and 270 species, which, like other deep sea creatures, exhibit bizarre behaviors and peculiar anatomical features to survive in their extreme environment.

Stomiids have a long body that typically lacks scales, a series of light-emitting organs called photophores along their body, and a photophore-containing string-like structure called a barbel hanging from their chin whose light may be used to attract prey toward the dragonfish’s very toothy mouth…

(read more: Smithsonian Ocean Portal

(photos: Nalani Schnell)

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