Now that’s a mouthful

A new study released in the journal Microbiome (it’s open-access!) has concluded that “intimate kissing” that lasts at least 10 seconds can transfer 80,000,000 bacteria between the participants’ mouths. So many microbes sloshing around – it’s a little bit gross, a little bit cool, and 100% science.

NPR wrote a short piece about it here.

What’s lurking on your glabella

Figure 1 from Grice and Segre (2011), showing the distribution of viruses, bacteria, fungi and mites on our skin and where glands and hair follicles originate.

Figure 1 from Grice and Segre (2011), showing the distribution of viruses, bacteria, fungi and mites on our skin and where glands and hair follicles originate.

Our skin is an amazing organ – it keeps our guts in and intruders out. We have an average of 1.8 m2 and this area contains many distinct regions that vary in pH, temperature, moisture, exposure, etc. Your forearm is dry, your cheeks are oily and your elbow crease is considered “moist”. Hair follicles, pores, glands, nails – if we think of our bodies as planets, there are a lot of different habitats. And it turns out our habitats are home to many, many things.

Oh et al. (2014) analyzed 263 samples from 15 human beings at 18 habitats (anatomical skin sites). They were interested in the biogeography of skin – and how it varies between people and across habitats. Do all forearms look alike? Do all “dry” habitats have similar function? It was already known that there are large scale microbial diversity patterns in the skin microbiome. For example, oily sites contain relatively low taxonomic diversity, perhaps because these sites are most selective when it comes to who is able to live there. At the other end of the diversity spectrum are dry sites, which tend to have high diversity.

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So that’s where the penis comes from!

Well, the title pretty much says it all – two recent studies shed some light on the biological origin of the wiener.

Today, two teams of researchers report having solved one part of this mystery, pinpointing how the organ gets its start in snake, lizard, mouse, and chick embryos. Now that they understand the penis’s origin, researchers can track its development in more detail to understand what drives it to follow a different path in females and become a clitoris. The finding doesn’t just answer a biological conundrum; it could also help millions of people born with genital malformations.

Read the research highlight in full here.

Crazy cool picture of a snake embryo, complete with tiny penis buds instead of legs.

We’re Not Going To Take It ( #NAWD )

“Adjunct” is the word for non-tenure track faculty positions at universities. They are generally low-paying (without benefits), utterly lacking in job security and can even lead to questionable hires (further reviewed here). The reliance on and mistreatment of cheap PhDs to teach undergraduate courses may have finally reached some sort of tipping point – February 25, 2015 is National Adjunct Walkout Day. They have a group on Facebook and are using the hashtag #NAWD on twitter. Read more about the “adjunct crisis” and the walkout here or here.

And if you’re an adjunct planning on participating, a student being taught by adjunct faculty, a tenure track faculty at a university using adjuncts to teach courses or basically anyone else, I’d love to hear your thoughts! Personally, I can’t get “We’re Not Going To Take It” out of my head…

Did someone say coffee?

Boy howdy, do I need love coffee. Drinking coffee feels like it’s in my blood. Perhaps literally. A recent study has identified some pretty interesting genes linked to coffee consumption.

They also found two regions of DNA near genes called BDNF and SLC6A4 that might play a role in how caffeine affects the brain by positive reinforcement. The study participants with a certain variant, who secrete less BDNF, may feel less of the rewarding effects of drinking coffee, according to the study. But the bigger coffee drinkers were more likely to have a certain variant of the SLC6A4 gene, which encodes a protein that transports the brain chemical serotonin.

Read more about the results here.

No, wait. Scratch that. I don’t.

Some are born great…

There has been a lot of interest throughout history in what makes great people great. Like the freakishly great people. The Yo-Yo Mas and the Michael Jordans, if you will. Some research pointed to genetics. Some research pointed to practice making perfect (ever heard of the “10,000 hours” rule?). An article in Slate, “Practice Does Not Make Perfect” sums up some pretty compelling evidence that genes play a mighty big role in all sorts of aptitudes.

In a recently published analysis of the data, researchers found that there was a stronger correspondence in drawing ability for the identical twins than for the fraternal twins. In other words, if one identical twin was good at drawing, it was quite likely that his or her identical sibling was, too. Because identical twins share 100 percent of their genes, whereas fraternal twins share only 50 percent on average, this finding indicates that differences across people in basic artistic ability are in part due to genes. In a separate study based on this U.K. sample, well over half of the variation between expert and less skilled readers was found to be due to genes.

And if you’re already thinking about the implications and ramifications of snubbing practice because it all comes down to genetics, the article discusses that (in depth) too.

It is therefore crucial to differentiate between the influence of genes on differences in abilities across individuals and the influence of genes on differences across groups. The former has been established beyond any reasonable doubt by decades of research in a number of fields, including psychology, biology, and behavioral genetics. There is now an overwhelming scientific consensus that genes contribute to individual differences in abilities. The latter has never been established, and any claim to the contrary is simply false.

 

How much would I have to practice before I could run as fast as Usain Bolt? My guess is infinity.