The tiny cyanobacteria use the principle of the lens in the human eye to perceive light direction

Scientists have been trying to figure out how it is possible for bacteria to perceive light and react to it ever since they started using microscopes 300 years ago. Scientists have now solved this riddle: In studies on so-called cyanobacteria, the researchers demonstrated that these tiny organisms of only a few micrometers in size move toward a light source using the same principle of the lens in the human eye. —> Read More

Toxoplasmosis: Morbid attraction to leopards in parasitized chimpanzees

Researchers have shown that chimpanzees infected with toxoplasmosis are attracted by the urine of their natural predators, leopards, but not by urine from other large felines. The study suggests that parasite manipulation by Toxoplasma gondii is specific to each host. It fuels an ongoing debate on the origin of behavioral modifications observed in humans infected with toxoplasmosis: they probably go back to a time when our ancestors were still preyed upon by large felines. —> Read More

How Babies See The World Differently From Adults May Surprise You

The brains of 3-month-old babies may not be fully developed, but they do possess some striking perceptual abilities that adults don’t even have.

New research finds that 3- and 4-month-old infants have unusual visual skills, which allow them to pick out differences in images that adults can’t see — an ability that they lose around the 5-month mark.

Since these babies haven’t yet developed perceptual constancy, a skill that allows us to recognize the same object as being the same in different environments and lighting, they are more able to notice subtle differences in images, such as illumination, according to the Japanese study, which was published in the journal Cell Biology in December.

Susana Martinez-Conde, a neuroscientist at the State University of New York, told The Huffington Post there’s a perceptual narrowing that babies experience. “This means that when they’re born, they’re highly responsive to all sorts of variations in the world,” said Martinez-Conde, who was not involved in the study. “As babies, we have all the capability to perform high-level discriminations. As we grow up, our discimination skills narrow and we are left with only a constrained range of the differences that we are able to appreciate.”

Martinez-Conde reported in the Scientific American last week that the illusion of constancy is an evolutionary adaptation that helped early humans to survive by allowing us to identify important objects despite changes in our physical environment.

“At first we see all differences, and then we learn to ignore certain types of differences so that we can recognize the same object as unchanging in many varied scenarios,” Martinez-Conde wrote in SciAm. “When perceptual constancy arises, we lose the ability to detect multiple contradictions that are nevertheless highly noticeable to young babies.”

Here’s an example, taken from the new —> Read More

Fossils turn out to be a rich source of information

For more than 70 years, fossilized arthropods from Quercy, France, were almost completely neglected because they appeared to be poorly preserved. With the help of the Synchrotron Radiation Facility ANKA at the Karlsruhe Institute of Technology (KIT), an international and interdisciplinary team of researchers with substantial participation from the University of Bonn has now been able to X-ray the 30-million-year-old beetle fossils. The internal structures are shown in such detail that the scientists were able to create an extensive description and an evolutionary analysis of the beetles. The results of this study have now been published in the professional journal eLIFE. —> Read More

What Scientists Mean When They Say ‘Race’ Is Not Genetic

If a team of scientists in Philadelphia and New York have their way, using race to categorize groups of people in biological and genetic research will be forever discontinued.

The concept of race in such research is “problematic at best and harmful at worst,” the researchers argued in a new paper published in the journal Science on Friday.

However, they also said that social scientists should continue to study race as a social construct to better understand the impact of racism on health.

So what does all this mean? HuffPost Science recently posed that question and others to the paper’s co-author, Michael Yudell, who is associate professor and chair of community health and prevention at the Dornsife School of Public Health at Drexel University in Philadelphia.

Why is it problematic to view race as a biological concept?

For more than a century, natural and social scientists have been arguing about whether race is a useful classificatory tool in the biological sciences — can it elucidate the relationship between humans and their evolutionary history, between humans and their health. In the wake of the U.S. Human Genome Project, the answer seemed to be a pretty resounding “no.”

In 2004, for example, Francis Collins, then head of the National Human Genome Research Institute and now director of the National Institutes of Health, called race a “flawed” and “weak” concept and argued that science needed to move beyond race. Yet, as our paper highlights, the use of race persist in genetics, despite voices like Collins, like Craig Venter — leaders in the field of genomics — who have called on the field to move beyond it.

We believe it is time to revisit this century-long debate and bring biologists, social scientists and scholars from the humanities together in a constructive way —> Read More

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