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August 03, 2010

Triceratops or Torosaurus?

The triceratops was the juvenile form of the torosaurus, but everyone likes the triceratops name better. Which will win the naming war: scientific fact or popular opinion? Morph-osaurs: How shape-shifting dinosaurs deceived us - life - 28 July 2010 - New Scientist
Triceratops had three facial horns and a short, thick neck-frill with a saw-toothed edge. Torosaurus also had three horns, though at different angles, and a much longer, thinner, smooth-edged frill with two large holes in it. So it's not surprising that Othniel Marsh, who discovered both in the late 1800s, considered them to be separate species. Now Scannella and Horner say that triceratops is merely the juvenile form of torosaurus. As the animal aged, its horns changed shape and orientation and its frill became longer, thinner and less jagged. Finally it became fenestrated, producing the classic torosaurus form (see diagram, right). This extreme shape-shifting was possible because the bone tissue in the frill and horns stayed immature, spongy and riddled with blood vessels, never fully hardening into solid bone as happens in most animals during early adulthood. The only modern animal known to do anything similar is the cassowary, descended from the dinosaurs, which develops a large spongy crest when its skull is about 80 per cent fully grown.

July 31, 2010

Salamander discovered to contain symbiotic photosynthesizing algae

A solar salamander : Nature News
Ryan Kerney of Dalhousie University in Halifax, Nova Scotia, Canada, did just that while looking closely at a clutch of emerald-green balls — embryos of the spotted salamander (Ambystoma maculatum). He noticed that their bright green colour comes from within the embryos themselves, as well as from the jelly capsule that encases them. This viridescence is caused by the single-celled alga Oophilia amblystomatis. This has long been understood to enjoy a symbiotic relationship with the spotted salamander, which lays its eggs in bodies of water. However, the symbiosis was thought to occur between the salamander embryo and algae living outside it — with the embryo producing nitrogen-rich waste that is useful to algae, and the algae increasing the oxygen content of the water in the immediate vicinity of the respiring embryos. At a presentation on 28 July at the Ninth International Congress of Vertebrate Morphology in Punta del Este, Uruguay, Kerney reported that these algae are, in fact, commonly located inside cells all over the spotted salamander's body. Moreover, there are signs that intracellular algae may be directly providing the products of photosynthesis — oxygen and carbohydrate — to the salamander cells that encapsulate them.

July 28, 2010

Jellyfish genes show the origin of all eyes

Jellyfish Eyes Solve Optical Origin Mystery | Wired Science | Wired.com
Eyes are one of evolution’s marvels, described by Darwin as “an organ of extreme perfection.” But whether the animal kingdom’s kaleidoscope of eyes evolved from a common structure, or separately in dozens of forms, is a nagging evolutionary question. Now a study of optical genes in jellyfish, which are descended from creatures that swam Earth’s ancient seas, long before vertebrates and invertebrates took their separate paths, suggests a common optical origin. “Eyes have evolved in parallel many times, but they all go back to one prototype,” said University of Basel cell biologist Walter Gehring.

Scientists harvest venom from antarctic octopus

It's possible that all octopuses are venomous. Scientists tap into Antarctic octopus venom
Venom has long been recognised as a potentially valuable resource for drug development. However, scientists have only recently discovered the largely untapped resource cephalopods such as octopuses, cuttlefish and squid, possess in their unique venom properties -- especially the species that live in sub-zero temperatures. Team Leader, Dr Bryan Fry from the Bio21 Institute says it was a mystery how venomous animals have adapted their venom to have an effect even in sub-zero temperatures, where most venoms would normally lose their function. "This is the first study that has collected Antarctic octopus venom and confirmed that these creatures have adapted it to work in sub zero temperatures -- the next step is to work out what biochemical tricks they have used," he says. Dr Fry says the venom analysis revealed that Antarctic octopus venom harbours a range of toxins, two of which had not previously been described. "We have discovered new small proteins in the venom with very intriguing activities -- these are potentially useful in drug design, but more will be revealed as the study continues," he says.

July 14, 2010

What, If Anything, is Big Bird?

An actual scientific presentation, gone very, very right. What, if Anything, Is Big Bird?