Life Sciences
ksharpe | March 17, 2009Originally posted by Grrlscientist
On March 14, 2009, at 10:59 AM
An ocean without its unnamed monsters would be like a completely dreamless sleep.—John Steinbeck, The Log from the Sea of Cortez (Penguin Classics; 1995).
Unlike any of the kids I grew up with, I was absolutely fascinated by sharks. Despite their bloodthirsty reputation, I saw them as elegant and beautiful creatures, although I never appreciated them as individual personalities. But when you read journalist Susan Casey's book, The Devil's Teeth: A True Story of Obsession and Survival Among America's Great White Sharks (Henry…
laelaps | March 17, 2009
A mount of Dimetrodon at the AMNH. From the Bulletin of the AMNH.
The predatory pelycosaur Dimetrodon has always been a favorite of mine. Though not a dinosaur it has an appearance as bizarre as any dinosaur you care to name, and the function of the huge sail on its back is remains an enigma. What could such an impressive structure be used for?
Slight differences in the bony back struts of a similar animal that inhabited the same habitat as Dimetrodon provided paleontologist E.D. Cope with a clue. Where Dimetrodon was a large apex predator "Naosaurus" appeared to be a more peaceful…
laelaps | March 16, 2009
A visual summary of horse evolution published in 1921 (derived from an earlier diagram by W.D. Matthew). From An Introduction to the Study of Fossils.
When Charles Darwin published On the Origin of Species by Means of Natural Selection in 1859 he faced a substantial problem. His evolutionary mechanism predicted that the fossil record would contain finely-graded transitions revealing what G.G. Simpson would later term the "tempo and mode" of evolution, yet such transitional creatures proved elusive. This was a major problem for paleontologists who believed that studies of European geology…
tetrapodzoology | March 16, 2009
Already the article you're reading is several weeks late, and I had to make a real effort to finish it before those weeks became months. Anyway, I present here the penultimate in the 'month in dinosaurs (and pterosaurs)' series (for the previous articles please see part I, part II, and part III). The whole point of this little series was to discuss what happened during January 2009 in dinosaur and pterosaur research. So, we've done the dinosaurs (or, at least, the theropods and ornithischians). This time: pterosaurs. Before launching into the new stuff, I must note that a single, exceptional…
clock | March 14, 2009
Help scientists track plant and animal cycles:
The USA-National Phenology Network (USA-NPN) -- a University of Arizona, Tucson-based group of scientists and citizens that monitors the seasonal cycles of plants and animals -- is calling for volunteers to help track the effect of climate change on the environment.
The group is launching a national program encouraging citizen volunteers to observe seasonal changes among plants and animals, like flowering, migration and egg-laying. They can then log in and record their observations online at the USA-NPN website.
"The program is designed for…
evolvingthoughts | March 14, 2009A while back I excerpted some Whewell on classification by types. Here is John Stuart Mill disagreeing with him, and, I think, starting off the modern literature on natural kinds.
Kinds are Classes between which there is an impassable barrier; and what we have to seek is, marks whereby we may determine on which side of the barrier an object takes its place. The characters which will best do this should be chosen: if they are also important in themselves, so much the better. When we have selected the characters, we parcel out the objects according to those characters, and not, I conceive,…
grrlscientist | March 14, 2009tags: The Devil's Teeth: A True Story of Obsession and Survival Among America's Great White Sharks, Susan Casey, science, adventure, memoir, book review
An ocean without its unnamed monsters would be like a completely dreamless sleep.
-- John Steinbeck, The Log from the Sea of Cortez (Penguin Classics; 1995).
Unlike any of the kids I grew up with, I was absolutely fascinated by sharks. Despite their bloodthirsty reputation, I saw them as elegant and beautiful creatures, although I never appreciated them as individual personalities. But when you read journalist Susan Casey's book, The Devil's…
clock | March 12, 2009So, let's see what's new in PLoS Genetics, PLoS Computational Biology and PLoS Pathogens this week. As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers. Here are my own picks for the week - you go and look for your own favourites:
Abnormal Brain Iron Homeostasis in Human and Animal Prion Disorders:
Prion disorders are neurodegenerative conditions of humans and animals that are invariably fatal. The main agent responsible for neurotoxicity in all prion disorders is PrP-scrapie (PrPSc), a β-sheet rich isoform of a normal cell-…
ksharpe | March 12, 2009Originally posted by Brian Switek
On March 10, 2009, at 11:14 AM
In 1857 Richard Owen proposed that our species, Homo sapiens, belonged to a distinct subclass separate from all other primates. He called this new group the Archencephala and based it as much upon human powers of reason as minute neuroanatomical differences between apes and humans. What's more, our "extraordinarily developed brain[s]" not only placed us above all other creatures but gave us new moral responsibilities, and in closing Owen stated;
Thus [Man] fulfils his destiny as the master of this earth, and of the lower…
clock | March 12, 2009First Right Whale Sedation Enables Disentanglement Effort:
For the first time ever, rescuers used a new sedation delivery system to help free an entangled North Atlantic right whale. The new system was developed at Woods Hole Oceanographic Institution in collaboration with NOAA and the Univ. of Florida and the Univ. of Wisconsin veterinary schools to make the animals more approachable by rescue boats.
Biologists Find World-record Colony Of Amoeba Clones In Texas Cow Pasture:
A Rice University study of microbes from a Houston-area cow pasture has confirmed once again that everything is bigger…
evolvingthoughts | March 11, 2009Taxonomy - the science of classifying organisms into putatively natural groups - is often treated as a kind of necessary bit of paperwork without much theoretical import by some biologists. Others think it is the single most important thing to do, usually justifying it in terms of conservation biology, but sometimes in terms of foundational knowledge. One thing that has become clear to me is exactly how foundational taxonomy is. Now, historian Polly Winsor has published a paper in the leading taxonomic journal, appropriately named Taxon, in which she argues, I believe correctly, that Darwin's…
edyong | March 11, 2009Tigers can no more change their stripes than leopards can change their spots. That's a good thing too, for their unchanging patterns, as individually distinct as a human fingerprint, make it easier to track any single tiger over time.
That process is about to become even simpler with a computer programme that creates a three-dimensional model of a tiger's skin and can compare different shots of an animal taken at different times or angles. The programme is the brainchild of Lex Hilby from an organisation called Conservation Research and it could allow conservationists to track surviving…
clock | March 11, 2009American Carnivores Evolved To Avoid Each Other, New Study Suggests:
How do the many carnivorous animals of the Americas avoid competing for the same lunch, or becoming each other's meal? A possible answer comes from a new study by a pair of researchers at the University of California, Davis. Their large-scale analysis shows that it's not just chance that's at play, but avoidance strategies themselves that have been a driving force in the evolution of many carnivores, influencing such factors as whether species are active daytime or nighttime, whether they inhabit forests or grasslands, or…
clock | March 10, 2009I know, I know, I've been traveling so I've been remiss at highlighting the best new articles over the past few days. In the meantime, we published 25 new articles on Friday night, 29 new articles last night, and 30 new articles tonight in PLoS ONE. So, there is a whole lot of them to check out, and as always, I will showcase below some of the stunningly good ones and some I personally am interested in. As always, you should rate the articles, post notes and comments and send trackbacks when you blog about the papers. You can now also easily place articles on various social services (…
edyong | March 10, 2009You're looking at the face of a new species of fish and judging by the two fearsome fangs, you'll probably understand how it got its scientific name - Danionella dracula. The teeth do look terrifying but fortunately, their owner is a tiny animal just 15 millimetres long. Ralf Britz from London's Natural History Museum discovered the fanged fish in a small stream in northern Burma, just two years ago. The more he studied them, the more he realised that they are physically extraordinary in many ways.
For a start, those are no ordinary teeth - they are actually just part of the fish's jawbone…
laelaps | March 10, 2009
In 1857 Richard Owen proposed that our species, Homo sapiens, belonged to a distinct subclass separate from all other primates. He called this new group the Archencephala and based it as much upon human powers of reason as minute neuroanatomical differences between apes and humans. What's more, our "extraordinarily developed brain[s]" not only placed us above all other creatures but gave us new moral responsibilities, and in closing Owen stated;
Thus [Man] fulfils his destiny as the master of this earth, and of the lower Creation.
Such are the dominating powers with which we, and we alone,…
edyong | March 10, 2009If you wanted to turn a rat into a fearless critter, unfazed by cats or bigger rats, the best way would be to neutralise a small pair of tiny structures in its brain called the dorsal premammillary nuclei, orPMD. According to new research by Simone Motta at the University of Sao Paolo, these small regions, nestled within a rat's hypothalamus, control its defensive instincts to both predators and other rats.
But not all neurons in the PMD are equal. It turns out that the structures are partitioned so that different bits respond to different threats. The front and side parts (the ventrolateral…
laelaps | March 9, 2009
From Life.
Starting on May 1, 1901 the great Pan-American Exposition delighted visitors for six months in Buffalo, New York. Organized to "promote commercial and social interests among the States and countries of the Western Hemisphere" the show displayed the modern wonders of art, science, and technology. Among the varied exhibits was Esau the chimpanzee.*
*[The infamous "Cardiff Giant" was also on display.]
Featured in the exhibit "The Evolution of Man", Esau was among the first performing apes in America. Others, like the first incarnation of Consul, had come before in Europe, but Esau…
grrlscientist | March 8, 2009tags: Birdbooker Report, bird books, animal books, natural history books, ecology books
"One cannot have too many good bird books"
--Ralph Hoffmann, Birds of the Pacific States (1927).
The Birdbooker Report is a special weekly report of a wide variety of science, nature and behavior books that currently are, or soon will be available for purchase. This report is written by one of my Seattle birding pals and book collector, Ian "Birdbooker" Paulsen, and is edited by me and published here for your information and enjoyment. Below the fold is this week's issue of The Birdbooker Report which…
edyong | March 8, 2009
Imagine that you're driving along a country lane. As often happens, the road suddenly transforms from a well-paved street to a pothole-ridden nightmare. As your suspension and your stomachs start to tire, your friends in the back suddenly force you to stop the car.
To your amazement, they jump out and lie across the potholes, beckoning you to drive your car over them. It may seem like a far-fetched scenario, but if you were an army ant, such selfless behaviour would be a matter of course.
Army ants are some of the deadliest hunters of South America. Amassing in legions of over 200,000 ants…