Penumbral Lore; the Shadows of Science

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Science for Your Amusement

Earliest chocolate drinks were alcoholic (but they already knew that), and 500 years earlier than previously thought. Archaelology Online and Dogfish Head Brewery may try to ‘reconstruct the brew. They previously did the same thing with Chateau Jiahu, which just might (probably not) be still available…

Here’s the abstract to the article “Ovulatory cycle effects on tip earnings by lap dancers: economic evidence for human estrus?” from “Evolution and Human Behavior”. A silly study, but it does have something to say about the concept of concealed ovulation.

Finally, the US Government is suggesting that, in case of a deadly influenza pandemic, Homeland Security gets preferential treatment - as though they’d be ‘on the front lines’ in response to the pandemic? Doesn’t make sense to me.

WLTX TV said the research was done “the University of Pittsburgh and the University of California at Santa Barbara”, didn’t report the authors or where it was published, but did draw its own conclusions about Keira Knightly and Jennifer Lopez.

ABC News took a more serious stance. See, a serious picture of a brain and everything! They mentioned that it had been published in the journal of Evolution and Human Behavior. It pointed out that the intelligence differences in the study, though statistically significant, are small. It also pointed out that the journal has published lots of sex stories in the past. It made sure to highlight that the study authors said that the ratio didn’t mean the same thing as the woman aged.

The Register was highly critical, called the researchers “US eggheads”, and made a bunch of statements about the change in the ratio since the 1950’s. (hint, guys … ‘foundation garments’)

The reporter at Associated Content took article as personally affirming. She also named the authors and linked to the study itself.

Waist-hip ratio and cognitive ability: is gluteofemoral fat a privileged store of neurodevelopmental resources? by William D. Lassek and Steven J.C. Gaulin

Only the abstract is available for free, but it’s worth reading.

The article is about teenaged mothers, the premise being that the lower WHC will have an effect as they are competing with their children for vital resources. As I read it, the abstract could be roughly paraphrased as “pregnant teens hurt their own brain development, and those of their babies. Maybe, if they’ve got a good reservoir of Omega-3 FAs stored up in bodacious booties, they’ll get some prediction… Looks like…”

Any speculation about evolutionary advantages was saved for the conclusion (but notice that that speculation made it into the news coverage oughtright…)

There’s been a lot of ‘health at any size’ stories lately. I urge you to look at them with some optimism, but to be aware that the reporter may not really ‘grok’ the research he or she is relaying to you. With that caveat, the New York Times reports that overweight people have lower mortality rates than obese people (expected) or than underweight people (I expected that, anyway) or than ‘healthy’ weight people (a surprise).

The cynic in me says that reporters are looking for stories to sell, and will eagerly ’spin’ any research to appeal to the largest possible audience (um… no pun intended…?) Demographics have got something to do with it. Possibly a growing awareness that the ‘think thin’ message we’ve been drowning under for years has produced an epidemic of eating disorders (as obesity continues to become more of a problem) is in the back of a science reporters mind as well, but mostly it’s a desire to make the story ‘interesting’.

I admit, I do tend to write about the story, then go off on my speculations and thoguhts on it, but at least I make an effort to be clear about what’s the research, and what’s my own thoughts on the research. If you ever catch me fuzzing that line, please comment and tell me!

So this wonderful article in the current “Undiscovered Planet“, which says that most of the different kinds of life on the planet are neither animal, plant, nor fungi, has inspired me to write a brief post on modern taxonomy (the naming of things). All the illustrations I use come from there, and I really suggest you follow the link and enjoy the whole article.

What I first heard of as “Super Kingdoms” are now known as “Domains”, and, according to the most recent schema, there are three of them. I hit wikipedia pretty hard for the rest of this article, so please feel free to let me know where I missed key points.

Eukarya (Eucaryotes) - organisms whose cells have organelles (little mini-organs) which are defined by cell membranes and cytoskeleton. The cytoplasm is the liquid inside the cells, the cytoskeleton is a set of filaments within the cytoplasm which are not separated by cellular membranes. The familiar multicelled organisms you see every day are all eucaryotes.

Bacteria are a group of organisms lacking organelles. They are pretty familiar, especially those which can make you sick. There’s a theory that some of the organelles of modern eukaryotes (like mitochondria and chloroplasts) were bacteria which formed a symbiotic relationship with the eukaryotes, and eventually the species merged so that one cannot exist without the other.

Archaea(which I first heard of as Archaeobacteria) are far more obscure. They’re like bacteria, in that they don’t have nuclei, but the way they translate DNA into protein is similar to the way eukaryotes do. The ’steroechemistry’ of the glycolipids (fats) in their cellular membranes is the mirror image of that for bacteria and eukaryotes, and is chemically distinct. None of the archaea conduct photosynthesis with an electric transport chain the way more familiar organisms do (though some do get their energy from light). Many metabolize methane. They live everywhere from deep sea vents to the inside of your digestive system, and are believed to be the oldest type of life on Earth.

The Archaea and Bacteria Domains are each comprised of a single ‘Kingdom’. The Eukaryote Domain contains four kingdoms - Protista, Fungi, Animalia and Plantae. Not surprisingly, these four are the first ones I learned about in school.

Plants are eukaryotes with and cell walls external to their outer cell membrane, and chloroplasts in their cytoplasm surrounded by two cell membranes. Photosynthesis takes place within the chloroplasts. Their reproductive cycle can get very complex, with alternation of sexual and asexual generations being just one example.

Animals are eukaryotes without cell walls which get their energy by digesting food. Most of them are multicellular, and go through a distinct, shared stage of embryological development called the blastula, which is a ball of cells around a hollow center. All animals are mobile for at least some period in their life cycle.

Fungi are eukaryotes with cell walls which get their energy by digesting food. There is an amazing range of fungal ‘behavior’ - some are single cellular. They form all kinds of symbiotic relationships (helpful, hostile or neutral) with plants and with animals. Like plants they can reproduce either sexually or asexually, but their sexual cycle is distinct - not all sexually active molds have two sexes, for example.

Protists are really a ‘catch all’ kingdom for eukaryotes which don’t belong in the other three. A few of them are multicellular. Slime molds, once considered to be fungi, are now grouped in with the protists. Likewise, protozoa are animal-like protists and algae are plant-like protists. Actually, some seaweeds are considered to be protists rather than plants, because their chloroplasts have three or four membranes surrounding them rather than two.

So, that’s the background.  Now go and read the article!