The Hardness of Squid Beaks

Abstract: The beak of the Humboldt squid Dosidicus gigas represents one of the hardest and stiffest wholly organic materials known. As it is deeply embedded within the soft buccal envelope, the manner in which impact forces are transmitted between beak and envelope is a matter of considerable scientific interest

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Challengers of the Unknown © DC Comics

Here, we show that the hydrated beak exhibits a large stiffness gradient, spanning two orders of magnitude from the tip to the base. This gradient is correlated with a chemical gradient involving mixtures of chitin, water, and His-rich proteins that contain 3,4-dihydroxyphenyl-L-alanine (dopa) and undergo extensive stabilization by histidyl-dopa cross-link formation.

These findings may serve as a foundation for identifying design principles for attaching mechanically mismatched materials in engineering and biological applications.

The Transition from Stiff to Compliant Materials in Squid Beaks. 2008. Ali Miserez et al. Science 319: 1816-1819.

Living Upside-Down Shapes Spiders for Energy Saving

Art by Frank Cho

Researchers investigating spider species which live, feed, breed and ‘walk’ in an upside-down hanging position have found that their lifestyle drives a shape in spiders that confers high energy efficiency, as in oscillatory pendulums.

The great majority of land animals evolved legs capable of supporting the weight of their whole bodies, enabling them to move around with their heads above their feet. However, many spider species found it more convenient to literally turn their world upside down. They spend most of their lives hanging suspended by their legs, and ‘walk’ by swinging under the influence of gravity.

One of the focal questions was the evolutionary importance of ‘bridging’ – the technique many spiders use to move between remote plants by building their own silk bridges, which they cross by ‘walking’ suspended upside-down from them. Earlier research by other authors indicated that for monkeys this suspensory way of locomotion might be a more energetically efficient way of transportation than ‘regular’ walking on the ground.

“We discovered that spiders that live upside-down have evolved disproportionately longer legs relative to ‘normal’ spiders, which enables them to move faster while bridging than while ‘normally walking’ on the ground. Particularly ‘clumsy’ walkers are larger spiders, because their long legs – otherwise so convenient for bridging – do not allow an easy lifting of their relatively large body mass” says Dr. Jordi Moya-Laraño from Spain, the principal investigator on this project.





These results have implications for the evolution and ecology of spiders. For example, small spiders that hang from their webs should be able to leave their webs in search for prey by walking on the ground, as found in some tiny spiders, something that large spiders will be unable to do efficiently. link

Ref: Morphological Evolution of Spiders Predicted by Pendulum Mechanics. 2008. Jordi Moya-Laraño et al. PLOS One e1841.

New Organic Molecule Discovered in Space

Art by Vaughn Bode and Larry Todd

Researchers from the Max Planck Institute for Radio Astronomy in Bonn have detected for the first time a molecule closely related to an amino acid: amino acetonitrile. The organic molecule was found in the "Large Molecule Heimat", a giant gas cloud near the galactic centre in the constellation Sagittarius.

The « Large Molecule Heimat » is a very dense, hot gas clump within the star forming region Sagittarius B2. In this source of only 0.3 light-year diameter, which is heated by a deeply embedded newly formed star, most of the interstellar molecules known to date have been found, including the most complex ones such as ethyl alcohol, formaldehyde, formic acid, acetic acid, glycol aldehyde (a basic sugar), and ethylene glycol.

Starting from 1965, more than 140 molecular species have been detected in space, in interstellar clouds as well as in circumstellar envelopes. A large fraction of these molecules is organic or carbon-based. A lot of attention is given to the quest for so-called "bio"-molecules, especially interstellar amino acids. Amino acids, the building blocks of proteins and therefore key ingredients for the origin of life, have been found in meteorites on Earth, but not yet in interstellar space.

Amino acetonitrile (NH2CH2CN)

The simplest amino acid, glycine (NH2CH2COOH), has long been searched for in the interstellar medium but has so far not been unambiguously detected. Since the search for glycine has turned out to be extremely difficult, a chemically related molecule was searched for, amino acetonitrile (NH₂CH₂CN), probably a direct precursor of glycine.

"Finding amino acetonitrile has greatly extended our insight into the chemistry of dense, hot star-forming regions. I am sure we will be able to identify in the future many new, even more complex organic molecules in the interstellar gas. We already have several candidates!" says Karl Menten, director at the Max Planck Institute for Radioastronomy. link

Just as long as they don't find, "The Green Slime"....!

Fear that Freezes the Blood in Your Veins

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"The blood froze in my veins" or "My blood curdled" – these common figures of speech can be taken literally, according to the latest studies. For it turns out that intense fear and panic attacks can really make our blood clot and increase the risk of thrombosis or heart attack.

Earlier studies showed that stress and anxiety can influence coagulation.A Bonn-based research team around Franziska Geiser (from the Clinic and Policlinic for Psychosomatic Medicine and Psychotherapy) and Ursula Harbrecht (from the Institute of Experimental Haematology and Transfusion Medicine) have been the first to conduct a very careful examination of coagulation in patients with anxiety disorders.

In the coagulation system two mechanisms operate that are indispensable to life and normally work in opposite directions, each counterbalancing the other. First, coagulation involves a thickening of the blood so that a plug can form and prevent excessive bleeding from damaged vessels. Second, there is "fibrinolysis", a process that keeps the blood fluid and breaks down clots. In the case of the anxiety-disorder patients, however, the researchers observed through close analysis of the blood an activation of coagulation accompanied by an inhibition of fibrinolysis. For these types of patients, the coagulation system goes out of balance as the coagulation tendency rises – possibly with dangerous consequences. In extreme cases the imbalance can lead to blockage of a coronary artery.

The increased coagulation tendency could, says Franziska Geiser, be the "missing link" that explains why anxiety patients have a statistically higher risk of dying from heart disease by a factor of 3 or 4. link

Sterankos' Batman

The Jam & Batman's Theme Song:

Neanderthals The Result of Genetic Drift

New research adds to the evidence that chance, rather than natural selection, best explains why the skulls of modern humans and ancient Neanderthals evolved differently. The findings may alter how anthropologists think about human evolution.

The study builds on findings from a study he and his colleagues published last year in the Journal of Human Evolution, in which the team compared cranial measurements of 2,524 modern human skulls and 20 Neanderthal specimens. The researchers concluded that random genetic change, or genetic drift, most likely account for the cranial differences.



In their new study, Weaver and his colleagues crunched their fossil data using sophisticated mathematical models -- and calculated that Neanderthals and modern humans split about 370,000 years ago. The estimate is very close to estimates derived by other researchers who have dated the split based on clues from ancient Neanderthal and modern-day human DNA sequences.



The close correlation of the two estimates -- one based on studying bones, one based on studying genes -- demonstrates that the fossil record and analyses of DNA sequences give a consistent picture of human evolution during this time period.



"A take-home message may be that we should reconsider the idea that all morphological (physical) changes are due to natural selection, and instead consider that some of them may be due to genetic drift," Weaver said. "This may have interesting implications for our understanding of human evolution." link

Close correspondence between quantitative-and molecular-genetic divergence times for Neandertals and modern humans. 2008. T. D. Weaver et al. PNAS, published on-line March 17, 2008.

Lobby cards from, "Creatures That Time Forgot".

Premiered This Day (1968): Barbarella

From the Jean-Claude Forest Home Page:

Jean-Claude Forest created the character of Barbarella for V-Magazine in 1962, at the request of its editor, Georges H. Gallet, who was already familiar with Forest's work as France's premier science fiction cover artist and had commissioned an illustrated version of Catherine L. Moore's classic story Shambleau in 1955.

Barbarella was published in book for by Eric Losfeld's publishing company Le Terrain Vague in 1964, became an immediate runaway bestseller and was soon translated in a dozen countries, including by Grove Press in the United States. Not long after, it was adapted into a 1968 motion picture, produced by Dino de Laurentiis, directed by Roger Vadim, and starring Jane Fonda, for which Forest acted as design consultant.

A Forest Barbarella design from the abandoned Nelvana animation project: