Category Archives: Life Science

Purple Frog Delights Scientists

Purple Frog photo

This interesting looking frog (N. sahyadrensis), discovered in India in 2003, has is in its own taxonomic family and represents the only known living example of frogs that lived alongside dinosaurs 65 million years ago, Purple frog delights scientists:

Its head appears too small for its body and it looks more like a squat, grumpy blob than a living creature.

But to the scientists who describe it in the journal Nature, the frog is a beautiful find because of what it tells them about Earth history.

“It is an important discovery because it tells us something about the early evolution of advanced frogs that we would not know otherwise because there are no fossil records from this lineage,” says Franky Bossuyt, of Free University of Brussels, Belgium.

Bee Colony Collapse Disorder

Bee Die-Off Threatens Food Supply:

In fact, about one-third of the human diet comes from insect-pollinated plants, and the honeybee is responsible for 80 percent of that pollination, according to the U.S. Department of Agriculture.

Still threatening the food supply seems like an extreme claim to me, but maybe I am just too optimistic.

Colony Collapse Disorder podcast:

In our first episode, hear from Senior Extension Agent and Honey Bee Specialist, Maryann Frazier, about honey bees and why they are such important pollinators in Pennsylvania and the United States. Find out why this die off is getting the attention of experts, and learn about the characteristics and extent of the collapse. Finally, get a preview of who the key players are and what is being done to investigate Colony Collapse Disorder.

Being Bad is Best for Bacteria

That conclusion is based on the first experiments investigating how natural selection influences the transmission of infectious disease. The outcome of those experiments defies old assumptions that pathogens evolve to become less infectious
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The scientists analyzed the patterns of disease transmission and found that strains of bacteria with the greatest damage to their virulence genes were slowest at spreading from one host to another. The strain of pathogen with all of its virulence genes intact spread the fastest. Strains of pathogen lacking the ability to inject any proteins into the host were completely unable to spread between hosts, suggesting that these swapped virulence genes are essential for spread.

Why do We Sleep?

Study puts us one step closer to understanding the purpose of sleep:

Sleep remains one of the big mysteries in biology. All animals sleep, and people who are deprived of sleep suffer physically, emotionally and intellectually. But nobody knows how sleep restores the brain.
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Although an electronic power-napper sounds like a product whose time has come, Tononi is chasing a larger quarry: learning why sleep is necessary in the first place. If all animals sleep, he says, it must play a critical role in survival, but that role remains elusive.

Based on the fact that sleep seems to “consolidate” memories, many neuroscientists believe that sleeping lets us rehearse the day’s events.

Tononi agrees that sleep improves memory, but he thinks this happens through a different process, one that involves a reduction in brain overload. During sleep, he suggests, the synapses (connections between nerve cells) that were formed by the day’s learning can relax a little.

Backyard Wildlife: Turtle

I took this photo in my back yard yesterday. It is the first time I have seen a turtle there. I saw a chipmunk today – I have see them occasionally but can’t get a photo of them – they move quite quickly 🙂 Other wildlife I have seen in my backyard: possum, raccoon, mole, fox, squirrels, rabbits, many birds including hawks and/or falcons, robins, starlings, doves, a humming bird once (front yard), butterflies, bats, lightning bugs, all sorts of bees, ants, praying mantis, and many more birds. And I see several cats prowl the yard frequently.

Hacking Your Body’s Bacteria

Hacking Your Body’s Bacteria for Better Health by Brandon Keim

In sheer numbers, bacterial cells in the body outnumber our own by a factor of 10, with 50 trillion bacteria living in the digestive system alone, where they’ve remained largely unstudied until the last decade. As scientists learn more about them, they’re beginning to chart the complex symbiosis between the tiny bugs and our health.

“The microbes that live in the human body are quite ancient,” says NYU Medical Center microbiologist Dr. Martin Blaser, a pioneer in gut microbe research. “They’ve been selected (through evolution) because they help us.” And it now appears that our daily antibacterial regimens are disrupting a balance that once protected humans from health problems, especially allergies and malfunctioning immune responses.

More on the Bee Deaths

Experts may have found what’s bugging the bees (link removed since content not freely available):

A fungus that caused widespread loss of bee colonies in Europe and Asia may be playing a crucial role in the mysterious phenomenon known as Colony Collapse Disorder that is wiping out bees across the United States, UC San Francisco researchers said Wednesday.

Researchers have been struggling for months to explain the disorder, and the new findings provide the first solid evidence pointing to a potential cause. But the results are “highly preliminary” and are from only a few hives from Le Grand in Merced County, UCSF biochemist Joe DeRisi said. “We don’t want to give anybody the impression that this thing has been solved.”

Other researchers said Wednesday that they too had found the fungus, a single-celled parasite called Nosema ceranae, in affected hives from around the country — as well as in some hives where bees had survived. Those researchers have also found two other fungi and half a dozen viruses in the dead bees.

N. ceranae is “one of many pathogens” in the bees, said entomologist Diana Cox-Foster of Pennsylvania State University. “By itself, it is probably not the culprit … but it may be one of the key players.”

Eat Less Salt – Save Your Heart

Reducing salt cuts cardiovascular disease risk:

Cutting back on salt intake could lower the risk of developing heart disease by 25 per cent, in addition to lower blood pressure benefits, say researchers who studied people with borderline high blood pressure. Researchers in the U.S. looked at more than 3,000 people in two trials with pre-hypertension who reduced their sodium intake by 25 per cent to 35 per cent, compared with control groups that did not.

Cut Heart Risk by Eating Less Salt:

Last summer, the American Medical Association (AMA) called for a minimum 50% reduction in sodium in processed foods, fast foods, and non-fast-food restaurant meals within a decade. The group also called on the FDA to work harder to educate consumers about the health risks associated with a high-sodium diet.

“The average American is eating three times as much salt as is healthy every day — the equivalent of 2 to 3 teaspoons instead of no more than 1,” he says. “The assumption tends to be, ‘If I don’t use my salt shaker much, I’m probably OK,’ but that just isn’t true.”

$600 Million for Basic Biomedical Research

Howard Hughes Medical Institute (HHMI) will hold a national competition for investigators that will result in an investment of at least $600 million in basic biomedical research. Up to 50 new researchers will be selected by spring 2008. HHMI Announces New Open Competition:

HHMI seeks applications from outstanding scientists studying biomedical problems in a broad array of disciplines, including not only biology and medicine, but related areas of chemistry, physics, engineering and computational biology. This competition is open to early career stage scientists at approximately 200 eligible institutions.
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HHMI values innovation and encourages its investigators to extend the boundaries of science. By appointing scientists as Hughes investigators — rather than awarding research grants — HHMI is guided by the principle of “people, not projects.” HHMI investigators have the freedom to explore and, if necessary, to change direction in their research. Moreover, they have support to follow their ideas through to fruition — even if that process takes many years.
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This new competition represents the first time that HHMI has opened up a general competition to the direct application process. In the past, faculty members had to be nominated by their institutions for HHMI investigator positions.

More details and apply via: 2008 HHMI Investigator Competition.

T-rex Treasure

T. rex remains yield new treasure

Already, the breakthrough has yielded a payoff. Schweitzer and the Harvard scientists found molecular similarities between the Tyrannosaurus rex and modern chickens. They say the finding strengthens a growing case that birds are living relatives of dinosaurs. More tests are needed to see whether the bits of dinosaur proteins match those in other living creatures — including alligators and crocodiles, which, by outward appearances, seem closely related to the ancient species. Molecular maps of proteins in those reptiles are not yet available.
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The very existence of the molecular relics had been unimaginable. Until now, scientists thought such soft stuff survived no more than a million years in animal remains. Usually, tissue degrades and bone gets replaced by mineral, yielding fossils molded precisely like the originals. Although the fossils enable scientists to piece together a skeletal sketch of ancient life forms, they tell only so much.

The discovery of the protein fragments, detailed in the journal Science today, suggests that new molecular clues may be buried in other well-preserved fossils around the world. And those clues could help explain the biology of dinosaurs and other extinct animals. The newly discovered microscopic fragments are not DNA — the inherited code stored in billions of cells that defines every living creature. As a result, no one should expect any Jurassic Park-like replicas of dinosaurs to result from Schweitzer’s finding.