Life Sciences
clock | December 17, 2006Discovery May Help Predict When Toxoplasma Can Be Deadly :
Toxoplasma is arguably the most successful animal parasite on earth: It infects hundreds of species of warm-blooded animals, most notably half of humanity. Its unusual ability to overcome the numerous challenges of infecting and reproducing inside such a wide range of creatures has long intrigued scientists, and now researchers at the Stanford University School of Medicine have identified two of the proteins critical to its ability to thrive.
One Gene 90 Percent Responsible For Making Common Parasite Dangerous:
More than a decade of…
tfk | December 14, 2006China's white dolphin called extinct after 20 million years:
An expedition searching for a rare Yangtze River dolphin ended Wednesday without a single sighting and with the team's leader saying one of the world's oldest species was effectively extinct.
The white dolphin known as baiji, shy and nearly blind, dates back some 20 million years. Its disappearance is believed to be the first time in a half-century, since hunting killed off the Caribbean monk seal, that a large aquatic mammal has been driven to extinction.
A few baiji may still exist in their native Yangtze habitat in eastern China…
clock | December 13, 2006Embryonic Patterning Makes The Feathers Fly: Dots Versus Stripes In Chicken Feathers Controlled By Patterning Pathway :
At the American Society for Cell Biology's 2006 conference, scientists will describe their latest research on patterning, on the molecular and systems level.
Midges Send Undeniable Message: Planet Is Warming :
Small insects that inhabit some of the most remote parts of the United States are sending a strong message about climate change.
Research Highlights How Farmers' Agri-environment Schemes Could Do More For Wildlife:
New research offers an explanation for why numbers of…
revere | December 13, 2006Again, H5N1 is rewriting the book. Influenza A is usually thought of as an intestinal disease of birds. Surveillance and monitoring, therefore, has been carried out by sampling bird feces and cloacal (rectal) swabs. In a meeting in Singapore, however, the dean of flu virologists, Robert Webster of St. Jude's Children's Hospital in Memphis, is now reporting there are much higher H5N1 viral loads in the upper respiratory tract of birds than in the intestines. This is work done jointly with Albert Osterhaus in The Netherlands. It has led to changes in recommendations for detecting the virus in…
tsmith | December 12, 2006 I've written previously about how it's a bad idea to import exotic pets, after "exotic" African species of small animals were imported into the United States and housed alongside prairie dogs that were also to be sold as pets. The African animals brought along with them their own diseases, including monkeypox, which then spread to the prairie dogs and onto humans, causing at least 80 cases of monkeypox in the U.S.
Think this is a rare event, unlikely to re-occur? Think again. The Baltimore Sun has a story on how "exotic" pets like these African rodents enter the U.S. by the millions…
mixingmemory | December 12, 2006In the paper I discussed the other day, Atran and Norenzayan argue that one of the most important factors in determining whether a religious narrative is successful is how memorable it is. Easily remembered narratives get passed on, while difficult to remember narratives are forgotten. Thus, successful religious narratives will likely exhibit features that make them memorable. Norenzayan and Atran hypothesize that the feature shared by successful religious narratives (and cultural narratives in general) is that "they correspond to a minimally counterintuitive (MCI) cognitive template that…
tfk | December 8, 2006Scientists from the University of British Columbia have been following the oldest animals alive in unexpected places. Greenland sharks (Somniosus microcephalus) are believed to live several hundred years, and can reach sizes of several meters.
While they are usually found in cold, Arctic waters, the population that the GEERG has been following returns to the Saint Lawrence River every summer, disappearing as cold weather sets in.
Researcher Chris Harvey-Clark says that "all the papers published on the species, including magazine articles, can barely fill two shoeboxes," in part because of…
cortex | December 8, 2006The helter-skelter of urban life even affects birds. I swear my cockatiel is better behaved since I left London; now I know why:
Rapid urbanisation around the world and the subsequent increase in ambient noise has proven problematic for animals which use sound to communicate. For birds in particular, city noises can mask the exchange of vital information and prevent males from attracting mates.
To see how birds reacted to increased noise, Hans Slabbekoorn of Leiden University recorded the songs of great tits in 10 European cities including London, Prague, Paris and Amsterdam. He then compared…
jstemwedel | December 7, 2006I'd like to take a moment to consider a recent comment on a fairly old post about a class meeting wherein my students and I considered some of the inconsistent views about animals with which people seem to walk around. Here's what the commenter said:
"But, as one of my students put it, 'Some of these people who want to shut down the animal research facilities should put a sock in it while they're still eating meat.'"
This suggests that your classroom discussion created a false impression in your students, perhaps due to your own false assumptions.
I've campaigned for ten years to end harmful…
clock | December 5, 2006
No other aspect of behavioral biology is as well understood at the molecular level as the mechanism that generates and sustains circadian rhythms. If you are following science in general, or this blog in particular, you are probably familiar with the names of circadian clock genes like per, tim, clk, frq, wc, cry, Bmal, kai, toc, doubletime, rev-erb etc.
The deep and detailed knowledge of the genes involved in circadian clock function has one unintended side-effect, especially for people outside the field. If one does not stop and think for a second, it is easy to fall under the impression…
mikethemadbiologist | December 5, 2006I've posted before about the possible approval of cefquinome in agriculture, and why this is a stupid thing to even consider. So some colleagues and I got cranky and wrote a letter to the FDA.
Here's the letter:
Andrew C. von Eschenbach, M.D.
Acting Commissioner
U.S. Food and Drug Administration
5600 Fishers Lane,
Rockville MD 20857-000
Dear Acting Commissioner von Eschenbach,
We are writing to support the recommendation of the VMAC to reject and not approve the use of cefquinome, a fourth-generation cephalosporin antibiotic, for use in animal agriculture. One area that is critical in…
clock | December 3, 2006Daytime Sleepiness From Obstructive Sleep Apnea May Raise Risk For Cardiovascular Problems:
Obstructive sleep apnea (OSA), a sleep related breathing disorder that causes your body to stop breathing during sleep, can disturb your sleep numerous times on any given night. As a result, you may experience daytime sleepiness. Daytime sleepiness brought on by OSA may put you more at risk for cardiovascular problems, according to a study published in the December 1st issue of the journal SLEEP.
Scientists Identify Part Of Hummingbird's Tiny Bird Brain That Helps It Hover:
University of Alberta…
evolgen | December 1, 2006What if some phylogenies were simply irresolvable? That is, what if, no matter how much data we collected, it would be impossible to reconstruct, with a high level of certainty, an accurate representation of the tree of life? That would suck. A lot. I have mentioned how this can result from long branch attraction or lineage sorting. But are there any taxa where this appears to be a major problem?
Antonis Rokas and Sean Carroll have published an essay in PLoS Biology that addresses the issue of bushes (or irresolvable nodes) in the tree of life. They point out four clades in which no single…
tfk | November 30, 2006Chris Mooney finds Justice Scalia being proudly clueless as he prepares to decide whether the Clean Air Act requires the EPA to regulate carbon dioxide emissions, if it permits such regulation, or whether the state of Massachusetts has a right to even get into that argument.
JUSTICE SCALIA: your assertion is that after the pollutant leaves the air and goes up into the stratosphere it is contributing to global warming.
MR. MILKEY: Respectfully, Your Honor, it is not the stratosphere. It's the troposphere.
JUSTICE SCALIA: Troposphere, whatever. I told you before I'm not a scientist.
(Laughter…
cortex | November 29, 2006It's ironic that scientific research on animals has ended up becoming an important source of evidence against animal research. After all, it's only because we sacrifice chimps that we understand the deep connections between the chimp brain and the human brain. If we didn't experiment on rats, or dogs, or monkeys, then we wouldn't know about our shared biological architecture. As I noted a few months ago:
One of the great themes of post-Darwinian science is the inter-relatedness of life. From the perspective of our cells, there is little difference between a human and a rat, or even a sea slug…
purepedantry | November 27, 2006There you go, lemurs! Way to speciate:
The number of known species of the mouse lemur, the world's smallest primate, has increased by 25% with the description of three new species, bringing the total to 15.
Mouse lemurs are wide-eyed nocturnal animals that scamper around the forests of Madagascar, an island that harbors a tremendous diversity of wildlife.
Finding new examples of the tiny animals isn't a huge shock -- two new lemur species were reported in Madagascar just last year...Nonetheless, says Jorg Ganzhorn, head of the department of animal ecology and conservation at the University…
oracknows | November 27, 2006With the internecine sniping that's been going on lately throughout ScienceBlogs ove Larry Moran's intemperate "flunk the IDiots" and "Neville Chamberlain school of evolutionists" remarks, or, more specifically, whether opposing ID requires that one oppose religion in general as well, I hesitate to tread here. However, given my interest in the Holocaust, World War II history, and how Nazi racial hygiene programs laid the groundwork for Germany's plan to exterminate the Jews and all others viewed as threats to the regime, I can't resist putting my two cents in about this issue.
Before I…
pharyngula | November 20, 2006
I've been writing a fair amount about early pattern formation in animals lately, so to do penance for my zoocentric bias, I thought I'd say a little bit about homeotic genes in plants. Homeotic genes are genes that, when mutated, can transform one body part into another—probably the best known example is antennapedia in Drosophila, which turns the fly's antenna into a leg.
Plants also have homeotic genes, and here is a little review of flower anatomy to remind everyone of what 'body parts' we're going to be talking about. The problem I'll be pursuing is how four different, broadly defined…
evolvingthoughts | November 19, 2006Just because a bunch of German, French and British people invented geology some 200 or more years ago, all the "type locations" for the geological column have been defined in terms of Northern Hemisphere locations. Finally, though, we Australians have our own period, and it's a doozy - the earliest period in which multicellular life forms are recorded, before the Cambrian, from 542 to 635 million years ago.
For a while now, people have talked about the Vendian, but this wasn't an official name, and was based on a locale in Russia that could only be got to for a month or so a year, so the…
clock | November 18, 2006* Monkeys using perfume? Study investigates:
Some wild spider monkeys dab on a chewed-leaf paste that may act as a sort of cologne, researchers say.
* Red wine ingredient found to boost endurance:
A substance earlier linked to long life in animals, also "re-programs" muscle to double endurance, a mouse study indicates.
* Neanderthal DNA partially sequenced:
Scientists have preliminarily mapped out when the stocky human cousins diverged from our species.
* 'Dark energy' an age-old phenomenon, study finds:
A weird force pushing our universe outward has existed since near the beginning,…