Gut bacteria may cause diabetes

13 Friday Apr 2012

Tags

animals, biology, diabetes, Education, Health, Immune response, insulin, microbes, microbiome, Mouse, Popular science, science, TLR2

According to a recent study, your chances of developing adult onset diabetes may depend on what kind of bacteria are living in your gut. It’s been known for some time that type 2 diabetes can be caused by a combination of genetic and lifestyle factors; over the past few years, it’s become clear that these factors somehow interact with the microbiome, but the nature of this interaction and the microbiome’s role in determining susceptibility to diabetes hasn’t been properly explored. Last year a team of scientists from Brazil published results showing that changes in the community composition could completely reverse the effect of genetic factors.
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Excessive hygiene lets the immune system run amok

29 Thursday Mar 2012

Posted by sedeer in Bacteria, Immunology, Microbiology

≈ 8 Comments

Tags

Allergy, animals, Asthma, biology, colitis, Health, Hygiene Hypothesis, Immune system, Mouse, Popular science

Since moving to Finland, I’ve become accustomed to asking guests whether they have any allergies before I prepare dinner. I grew up in the developing world where allergies and asthma seem to be much less common than they are here; in fact, various studies have found higher rates of allergy and autoimmune conditions in developed than developing countries. One explanation for this is the “hygiene hypothesis“, which proposes that excessive hygiene early in life can affect the development of the immune system and result in allergic conditions and autoimmune diseases in later life. In a recent study appearing in Science, a team of scientists in Germany and the United States present evidence supporting the hygiene hypothesis and the importance of an early challenge to the immune system.
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Mammals didn’t have to wait for the dinosaurs to die out

24 Saturday Mar 2012

Posted by sedeer in Dinosaurs, Evolution, Mammals

≈ 1 Comment

Tags

adaptive radiation, animals, Cretaceous–Tertiary extinction event, dinosaur, diversity, mammal, Popular science, teeth

A study recently published in Nature challenges the prevailing wisdom that the extinction of the dinosaurs paved the way for an explosion of mammalian diversity. By studying the fossils of a group of mammals called multituberculates, the researchers have cast doubt on the traditional view of dinosaurs constraining small, shrew-like mammals to a secondary role as nocturnal insectivores. Instead, this group seems to have diversified millions of years before the dinosaurs died out.
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Social wasps are specialists at recognizing faces

16 Friday Mar 2012

Posted by sedeer in Evolution, Hymenoptera, Insects, Mind

≈ 3 Comments

Tags

animals, biology, Cognition, evolution, face, Facial recognition system, Insecta, Paper wasp, Popular science, science, Wasp

There’s lots of evidence that humans have a specialized mechanism for identifying and responding to faces; for example, people with a condition called prosopagnosia have difficulty recognizing faces but not other objects. A few years ago, researchers showed that individual paper wasps of the species Polistes fuscatus recognize each other’s faces; the same team has now gone on to show that, like humans, P. fuscatus accomplishes this via a specialized mechanism for facial recognition rather than through general shape or pattern recognition. This story is an excellent example of a complex cognitive ability being exhibited by a creature with a relatively simple nervous system.

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Redheads and pain: science or sensationalism?

12 Monday Mar 2012

Posted by sedeer in Genetics, Humans

≈ 2 Comments

Tags

animals, biology, Capsaicin, Human, Melanocortin 1 receptor, Pain, Popular science, Red hair, redhead, Redheads, science, science and society, Science communication

I’ve recently come across some press coverage reporting research by Danish scientists which has shown that “redheads feel pain differently than the rest of us”. I read the paper and thought it would be nice to write something short about it here, both for the change of tone and to give my own perspective on it.

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Thinking bees and the concept of “sameness”

22 Wednesday Feb 2012

Posted by sedeer in Hymenoptera, Insects, Mind

≈ 4 Comments

Tags

animals, bees, biology, Cognition, Hymenoptera, Insecta, Learning, Popular science, science

The ability to categorize objects or experiences as “the same” or “different” has generally been considered a relatively advanced cognitive capacity relegated solely to vertebrates (or perhaps even primates). However, in a study published in 2001, researchers found that honeybees are able to conceive of sameness and difference, showing that the capacity to make these abstract conceptual distinctions is more widespread than we had believed.