Note (12/2015): Hi there! I'm taking some time off here to focus on other projects for a bit. As of October 2016, those other projects include a science book series for kids titled Things That Make You Go Yuck! -- available at Barnes and Noble, Amazon and (hopefully) a bookstore near you!

Co-author Jenn Dlugos and I are also doing some extremely ridiculous things over at Drinkstorm Studios, including our award-winning webseries, Magicland.

There are also a full 100 posts right here in the archives, and feel free to drop me a line at with comments, suggestions or wacky cold fusion ideas. Cheers!

· Categories: Biology
What I’ve Learned:

Australopithecus: In hominid evolution, you win some, you Lucy some.
“Australopithecus: In hominid evolution, you win some, you Lucy some.”

Australopithecus sounds like an oddball instrument some grimy dreadlocked dude from New Zealand would play — or possibly a disease you might catch from said grimy Kiwi dude, if you stood too close to him during the concert.

Happily, Australopithecus is actually a genus — that is, a group of species — that lived in southern and eastern Africa between about two and four million years ago. The term “Australopithecus” means “southern ape”, which is a reasonable description of these hairy prehistoric hominid furballs.

(Also, it’s probably not a bad description of that nappy New Zealander. I’m just saying.)

The Australopithecus species — including the famous “Lucy” specimen — are particularly interesting, because they’re the earliest fossil remains of ape-like creatures that weren’t particularly ape-like. Though they had relatively small brains, analyses of Australopithecus toes, feet and hips reveal that they could probably walk upright. They may have also played hopscotch and danced the lambada on steamy Saturday nights.

(Those last bits aren’t really supported by the science. I just like to picture them.)

Also, most Australopithecus species have powerful teeth and jaws not seen in apes, and some may have even used tools. So they were no longer true apes; they were more like apes crossed with crocodiles who could walk on two legs and work a can opener, but probably played a lousy game of chess because their brains were still the size of golf balls.

Or, basically a pack of slightly-hairier Rachael Rays. I apologize in advance for the nightmares that phrase will surely cause.

Thus, Australopithecus has answered one important question about human evolution: the adaptation to stand upright was not driven by the development of a big, human-like brain. Early hominids were walking (and cooking 30-minute meals, apparently) before they had the ginormous craniums we’re all so proud of.

But another question remains: were the Australopithecus species, the original bipedal hairballs, direct ancestors of modern-day humans? It depends on who you ask.

(Just don’t ask Rachael Ray. She’s kind of sensitive about it.)

On one hand, there’s good evidence that Australopithecus species walked upright, and they have several features — like particular bone shapes and relative sizes — intermediate between earlier species’ skeletons and those found in doctors’ offices and Halloween costume shops today. Some scientists say: if it mostly waddles like a prehistoric duck, and it vaguely quacks like a prehistoric duck, then slap a mammoth skin on it and call it Daffy. For them, chances are we have Australopithecuses in our family tree.

Other scientists aren’t so sure. “Upright” is one thing, but these pre-humans probably didn’t walk or run like we do, and likely still climbed trees and “knuckle-walked” on a regular basis. Also, there were still Australopithecus species hanging around after the Homo genus emerged about 2.4 million years ago. Did the Homo species, including Homo sapiens — i.e., every human on the planet, except possibly Carrot Top — evolve from one of the earlier Australopithecus groups? Or intermingle with a later one? Did we evolve from a common ancestor, then watch their branch die out over the millennia?

At this point, nobody knows for sure. More fossil specimens — like the new species Australopithecus sediba, described in 2010 — may someday provide conclusive evidence of a link between the genuses. That would be exciting news, indeed.

Except then we’d have to invite Rachael Ray to the family reunions. And nobody wants to be at that potluck, Junior. Pass the prehistoric potato salad.

Image sources: Discovering Cultures (Australopithecus), Go, See, Write (dreadlocked dude), ResearchMatters/ASU and Armchair Cook (Rachael Ape), After and Before (Make-it-stop, Carrot Top)

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· Categories: Chemistry, Physics
What I’ve Learned:

Avogadro's number: That's a lot of MOOOOOOOOOLEcules!
“Sometimes, even a huge number can leave you wanting MOOOOOOLE!”

Contrary to popular belief, Avogadro’s number is neither the first item in a guacamole recipe, nor the less-successful Italian sequel to Schindler’s List. In fact, modern science says it isn’t officially a thing at all any more, like Pluto’s planethood or Steven Hawking’s dance moves.

Too soon? Sorry.

What is a thing is the Avogadro constant, which is closely related to the measurement known as a ‘mole’. The mole is a very important scientific concept, defined as the amount of a substance in grams equal to the atomic weight of that substance.

For pure elements, figuring a mole is easy. Take carbon, for instance. Carbon’s atomic weight is 12, so a mole of pure carbon — no radioactive isotopes, please — weighs 12 grams. Hydrogen’s a pipsqueak: atomic weight of 1, mole weight of 1. Californium is a beast of atomic weight 98, so a mole of that weighs a hefty 98 grams.

Must be all the Avogadro trees weighing it down.

Since larger atoms weigh more, every element — actually, every substance — has the same number of atoms in a mole. That number is Avogadro’s number, roughly equal to 6.022 x 1023.

(The “Avogadro constant” is basically the same as “Avogadro’s number”, after a bunch of snooty international standards paper-pushers got together and slapped official units on it to make it look pretty in scientific journals. What’s the precise relationship between the “number” and the “constant”? According to Wikipedia:

“Avogadro’s number is a dimensionless quantity and has the numerical value of the Avogadro constant given in base units.”

I know, right? It’s like reading Vogon poetry. Just say they’re the same thing, already, chem-nerds. Jesus.)

Calculating the amount, or molarity, of substances is trickier when they’re more complex — like cyclohexane or gummy bears or Chevrolet Impalas. But it’s still possible. You just figure out the average atomic weight of the molecules involved, plop the stuff on a scale and then calculate the number of moles involved.

(Well. You and I don’t. But other people do. The kind with lab coats and safety goggles and scientific calculators with the fancy buttons worn down.)

The key is Avogadro’s number, which is a pretty amazing thing itself. It’s a universal link between the mysterious world of atoms, which nobody understands, to the everyday world of grams — which only drug dealers and metric Europeans understand.

Also, it’s huge: six hundred and two sextillion, give or take a few quadrillion molecules. That many meters would equal 60 million light years, as far as the Virgo galaxy cluster. If it were gumballs, six hundred sextillion is almost — almost — more than Rachael Ray could fit into her mouth at once. So yeah, it’s a lot.

Yet all those molecules are jammed into 12 grams of carbon, less than half an ounce. It boggles the mind. And the Avogadros.

It even boggles the scientists. Chemists have taken to celebrating “Mole Day” each year, between the hours of 6:02AM and 6:02PM on 10/23. Because they haven’t received quite enough wedgies for sustained dorkiness, apparently.

You’d think they’d at least take it seriously — and not use it as an excuse to make constant “Mooooole!” jokes like a bunch of giddy four-eyed Austin Powers fanboys.

You would be wrong. Score one for Team Avogadro. Yeah, baby.

Image sources: Sturff (call me, Avogadro), Denver Westword (Rachael Ray piechasm), The Virtual School (molar eclipse), Lake Bluff Homebrew Club (Savage mole)

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