10/20/13

Infestations, Microbes & Parasites


Micrococcus (Actinobacteria)Staphylococci, Corynebacteria, Actinobacteria, Clostridiales, and Bacilli. They’re the most common, but they’re not the only ones. Bacteria. Microbes. Yes, even parasites.  Living in your belly button. And on your skin. Your hair. But the belly button flora and fauna fascinate me the most.*

We’ve known ever since the microscope was invented that we had a population of hitchhikers living on our skin, scalp – and even inside us. The great Antony van Leeuwenhoek is known as the “father of microbiology” for his explorations through his fledgling, primitive microscope in the late 17th and early 18th centuries. But we are still learning about the biodiversity we all have.**

There was a recent story in the Atlantic that researchers had found, of 2,368 species of bacteria living in our navels recorded so far, 1,458 new species.

New as in previously unknown until some scientist stuck a Q-tip into his or her belly button and examined the results. Which is what they are still doing, exploring this brave new frontier in microbiology. It must have been one of those eureka moments.

Gawd, dontcha love science? To bold go where no Q-tip has gone before…

The Atlantic story opens:

Instead of taking your fingerprint, maybe police should swab our belly buttons with Q-tips. No, that’s ridiculous, actually. But the idea illustrates a point made by a group of North Carolina-based researchers in their new Belly Button Biodiversity (BBB) project. Last month, the group published results of their first of many experiments, in which they swabbed 60 belly buttons and identified a total of 2,368 species of bacteria. People’s individual profiles were snowflake-ily, bacterially unique.

Most of the microbes that live on our skin are harmless, and many are actually beneficial: they protect us from more virulent invaders. What’s remarkable is the sheer number and variety of them.***

The scientists at Your Wildlife wrote that among all those species, there are some common forms found in most navels:

Turns out, belly buttons are a jungle of microbial biodiversity: we detected over 2300 species! And get this, only eight of those 2300 species– we call them oligarchs – were quite frequent and abundant, present in more than 70% of the individuals we sampled.

Oligarchs. Make me think of the Politburo. Or Putin’s new Russian clique. What role do these bacterial oligarchs play in their micro-environment?

We’re an entire ecosystem, Scientific American tells us:

Over the past 10 years or so, however, researchers have demonstrated that the human body is not such a neatly self-sufficient island after all. It is more like a complex ecosystem—a social network—containing trillions of bacteria and other microorganisms that inhabit our skin, genital areas, mouth and especially intestines. In fact, most of the cells in the human body are not human at all. Bacterial cells in the human body outnumber human cells 10 to one. Moreover, this mixed community of microbial cells and the genes they contain, collectively known as the microbiome, does not threaten us but offers vital help with basic physiological processes—from digestion to growth to self-defense.

By the way, you can contribute to this ongoing research; check the notes at yourwildlife.org about how to help. The belly button experiment is over, as researchers assess their samples, but they are moving on to armpits, a whole new territory.

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07/23/13

The colonization of land by life pushed back in time


Fossile lifeA recent story on Science Daily made me stop and read with fascination. It’s about the discovery of fossils that showed life colonized land more than two billion years ago. That’s a shocker, because all indicators are that the Earth was a hostile place, land was barren, and life was a lot simpler.

But apparently we underestimated the ability and tenacity of life. This gives us hope that life may exist on other planets or moons.

Mars, at least its surface, is unlikely to harbour life now, but may have in its water-rich past. We may find fossils. Europa, Jupiter’s ice-covered moon, may have life in the oceans under its surface. Finding out will be tough. Titan? A remote possibility. But these fossils give us new hope: life can survive in very hostile conditions.*

Conventional scientific wisdom has it that plants and other creatures have only lived on land for about 500 million years, and that landscapes of the early Earth were as barren as Mars. A new study, led by geologist Gregory J. Retallack of the University of Oregon, now has presented evidence for life on land that is four times as old — at 2.2 billion years ago and almost half way back to the inception of the planet.hat landscapes of the early Earth were as barren as Mars.

That raises several interesting ideas. First, what sort of life was it? The researchers don’t know for sure, but it’s a bit like slime mold or some lichen. It was tiny, but rather complex given its age and a promising candidate for the oldest known eukaryote. Sci-news notes:

Diskagma buttonii are very small – about 0.3 – 1.8 mm long. They most resemble modern soil organisms called Geosiphon, a fungus with a central cavity filled with symbiotic cyanobacteria.

It was something not quite animal or plant – something simple. But not that simple: they appear to have had symbiotic cyanobacteria in their interiors. Cyanobacteria appeared about 3 billion years ago, and started photosynthesizing (with water as a reducing agent) and making oxygen between then and about 2.6 billion years ago (life itself first showed up about 3.5 billion years ago but some estimates push it much earlier, to 4.3 billion).**

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