Scientific American - Biology

Women should undergo fewer Pap tests for cervical cancer, medical group says

Fri, 20 Nov 2009 14:25:00 EST

Just days after the release of controversial new guidelines recommending against routine mammograms for most women under 50, a different group of medical professionals has announced that the frequency of Pap tests for cervical cancer detection should also be decreased for most women. [More]

Plants Share Light If Neighbor Is Related

Fri, 20 Nov 2009 13:38:08 EST

We humans are known to help out members of our own families. When it comes to business we call it nepotism. Now plants have demonstrated the same predilection, in a study published in the American Journal of Botany . [More]

Readers Respond on "Do Parents Matter?"--And More...

Fri, 20 Nov 2009 09:00:00 EST

Parents and Peers As a psychologist very familiar with the research, I think in “ Do Parents Matter? ” Judith Harris is conflating personality and behavior, which are two different concepts. Personality has more to do with genetic traits related to mood and energy (which plenty of research indicates are strongly influenced by genetics). Behavior, on the other hand, depends on context and is guided by laws of behaviorism--that is, reinforcement principles. If parents do (or do not) provide reinforcement for specific types of behavior, you will either see or not see those behaviors. Likewise, certain behaviors will be reinforced in the classroom by teachers.

[More]

Why do human testicles hang like that?

Thu, 19 Nov 2009 18:06:00 EST

[More]

Cracked Corn: Scientists Solve Maize's Genetic Maze

Thu, 19 Nov 2009 17:48:00 EST

The complex corn genome--coming in at a hearty two billion base pairs (compared with the human genome's 2.9 billion base pairs)--has been mapped by more than 150 researchers, who worked for years to decipher the grain's genetic code . It's the most complicated plant genome to be deciphered to date and promises to increase the efficiency of the crop itself. [More]

How Humanlike Was "Ardi"?

Thu, 19 Nov 2009 11:30:00 EST

For such a petite creature, the 1.2-meter-tall " Ardi " ( Ardipithecus ramidus ) has made big waves in the paleoanthropology world. The momentous find--announced 15 years ago and formally described in Science this October--has deepened academic debates about when bipedalism evolved, what our last common ancestor with chimpanzees looked like, and how some ancient primates gave way to modern humans. [More]

Foreign Afflictions: Mental Disorders across Country Borders

Thu, 19 Nov 2009 09:00:00 EST

Let us start with a little quiz. How many of these conditions have you heard of?

Taijin kyofusho , hikikomori , hwa-byung , or qi-gong psychotic reaction.

[More]

BioScapes Photo Contest: 15 Honorable Mentions

Wed, 18 Nov 2009 13:30:00 EST

The entrants in the 2009 Olympus BioScapes International Digital Imaging Competition provide fitting tribute to nearly 1,000 years of making the invisible visible. These 15 photos were our staff favorites from the "Honorable Mentions" winners, listed in alphabetical order by photographer.

> 15 Scientific American Staff Selected Honorable Mentions [More]

Beyond the Still: 6 Bioscapes Contest Videos

Wed, 18 Nov 2009 13:29:00 EST

The entrants in the 2009 Olympus BioScapes International Digital Imaging Competition provide fitting tribute to nearly 1,000 years of making the invisible visible. These six videos include one winner and five Honorable Mentions.

[More]

Getting Those Varmints to Vamoose without Lethal Measures

Wed, 18 Nov 2009 13:00:00 EST

Dear EarthTalk: What would you recommend as a non-toxic/non-lethal way to keep squirrels, gophers and groundhogs away? --Faye Gillette, Coarsegold, CA

[More]

Government panel recommends fewer and later mammograms, no self-exams

Tue, 17 Nov 2009 18:25:00 EST

Most women would do fine to hold off until age 50 for their first mammograms and skip self-exams for breast lumps altogether, according to new government recommendations released Monday that came as a surprise to many in the medical community--and women in general. [More]

Bumping Off Bedbugs without Poison

Tue, 17 Nov 2009 13:00:00 EST

Dear EarthTalk: Why are bed bugs a big issue right now? Where do they come from and what real harm do they do? Are there non-toxic ways of dealing with them? --Harper H., Newburyport, MA

[More]

Ask the Brains: Are our Brains Constantly Making Subconscious Calculations?

Tue, 17 Nov 2009 09:00:00 EST

Is it true that when we drive, walk or reach for something our brain performs calculations? Is this ability learned or innate? --Helena Larks, San Francisco [More]

For Sale: Human Eggs Become a Research Commodity

Tue, 17 Nov 2009 08:00:00 EST

Paying a woman for her eggs to use in stem cell research has been a bioethical no-no for years. But this past June, New York State decided to allow just that, becoming the first state to permit public money to be used in this way. The decision, which allows payment of up to $10,000, will likely jump-start donations--and thereby research. Many bioethicists, however, worry that the financial incentive could exploit women and compromise their health.

Ethical issues surround egg donation because the process is not without risk. It requires a series of hormonal stimulation injections as well as an invasive procedure to retrieve the eggs. The long-term health effects and risks of complication are not well known. A woman who provides eggs for research is “assuming unknown risk for unknown benefits,” says Debra Mathews, a geneticist at Johns Hopkins University. The lingering unknowns prompted the National Academy of Science to issue in 2005 nonbinding guidelines to prohibit payment (but allow direct reimbursement for expenses), as a means to protect underprivileged women in particular.

[More]

Putting Madness in Its Place: Can the Environment Explain Schizophrenia's Hereditary Patterns?

Tue, 17 Nov 2009 08:00:00 EST

Schizophrenia hides its heritability well. Although fewer than 1 percent of the general population will be diagnosed as schizophrenic based on symptoms such as hallucination and disorganized thought, for children of a schizophrenic parent, those odds jump to about one in 10. And yet the condition’s genetic underpinnings have stubbornly resisted discovery. In the latest attempt, three crack teams of investigators pooled genomic data from 8,000 schizophrenics of European ancestry but could lay claim to only a handful of weak genetic risk markers.

Analyses such as these, which appeared online July 1 in Nature ( Scientific American is part of the Nature Publishing Group), have led researchers to question the value of brute-force genomics for analyzing schizophrenia. “I think we need to pause and think through the risk pathways to disease more clearly,” says Dolores Malaspina, director of the social and psychiatric initiatives program at New York University Langone Medical Center. In particular, devotees of genetics might want to cede a little ground to their colleagues in epidemiology, who over the past decade have amassed a provocative, interlocking set of studies implicating urban birthplace and migrant status as persistent risk factors.

[More]

Darwin in Battle of Wits against Unarmed Man

Tue, 17 Nov 2009 00:05:08 EST

November 24th marks the 150th anniversary of the publication of Darwin's Origin of Species . On November 19th, a guy named Ray Comfort, who does not accept evolution, will celebrate the fact that when copyrights expire and works enter the public domain you're free to do with them what you will. Thus Comfort will be distributing his own edition of Darwin’s masterwork, with a new introduction. This is roughly the equivalent of me fingerpainting on the ceiling of the Sistine Chapel so as to improve the work.

According to the folks at the National Center for Science Education, the NCSE, who monitor efforts to interfere with evolution education in public schools, Comfort in his intro repeats numerous familiar anti-evolution claims. For example, that there's a lack of transitional fossils and that the second law of thermodynamics makes evolution impossible. These assertions have been disproved more often than the chant "Yankees suck".

[More]

Grizzly Details: Salmon Collapse Could Be Bad News for Bears [Slide Show]

Mon, 16 Nov 2009 16:01:00 EST

For most of May Chris Darimont, an environmental scientist at the University of California, Santa Cruz , poured liters of fermented cattle blood mixed with pureed rotten fish guts on 3,000 square kilometers of British Columbia's coastal wilderness. [More]

Renewed Hope for an AIDS Vaccine

Mon, 16 Nov 2009 15:01:00 EST

The long search for an AIDS vaccine has produced countless false starts and repeated failed trials, casting once bright hopes into shadows of disenchantment. The now familiar swings appeared in high relief this past fall, with news of the most recent, phase III trial in Thailand . Initial fanfare for a protective outcome gave way to disappointment after reanalysis showed that the protection could be attributed only to chance. But rather than dashing all hopes for an AIDS vaccine, the trial has heartened some researchers, who see new clues in the battle against the fatal illness. [More]

Hive and Seek: Where Have the Honeybees Gone?

Mon, 16 Nov 2009 13:00:00 EST

Dear EarthTalk: Not long ago there were concerns about honey bees disappearing. Are the bees still disappearing, and if so do we know why and do we have a solution? --David, Grand Rapids, MI

[More]

The Will to Power--Is "Free Will" All in Your Head?

Mon, 16 Nov 2009 09:00:00 EST

Surely there must have been times in high school or college when you laid in bed, late at night, and wondered where your “free will” came from? What part of the brain--if it is the brain--is responsible for deciding to act one way or another? One traditional answer is that this is not the job of the brain at all but rather of the soul. Hovering above the brain like Casper the Friendly Ghost, the soul freely perturbs the networks of the brain, thereby triggering the neural activity that will ultimately lead to behavior.

Although such dualistic accounts are emotionally reassuring and intuitively satisfying, they break down as soon as one digs a bit deeper. How can this ghost, made out of some kind of metaphysical ectoplasm, influence brain matter without being detected? What sort of laws does Casper follow? Science has abandoned strong dualistic explanations in favor of natural accounts that assign causes and responsibility to specific actors and mechanisms that can be further studied. And so it is with the notion of the will.

[More]