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 secondhandscience@gmail.com with comments, suggestions or wacky cold fusion ideas. Cheers!

· Categories: Biology, Genetics
What I’ve Learned:

Convergent evolution: When great genes think alike.
“Convergent evolution: When great genes think alike.”

There’s no commandment in nature saying, “Thou shalt not covet thy neighbor species’ competitive survival advantage.” Mother Nature plays it pretty fast and loose with the rules.

For instance, say you’re a tree frog living high in the branches of some verdant tropical forest. Maybe some of your chittery squirrel pals have adapted their flappy limb skin and learned to glide gracefully from treetop to ground, whereas your species’ method for quick descent ends with a splat and an unfortunate frog-innard mess. Have you missed the gliding boat, simply because you decided to hop off the evolutionary squirrelhood branch before gliding came up?

Not at all, wartyballs. Because you can still develop gliding abilities on your own — completely separate from those showoff squirrels — in a process known as convergent evolution.

As processes go, convergent evolution is really just evolution, in an encore presentation. When the same environmental pressure is applied to different species, they may adapt in ways that appear similar, but are actually unique and occur entirely independently. So just because the tree rats figured out one way to glide doesn’t mean that the frogs can’t find another and glide alongside them. The squirrels don’t hold the patent on the technology; anybody with a flexible genetic code and a few millennia to burn can follow in their footsteps. Even Italian plumbers, apparently. Mother Nature’s not picky.

Are there other examples of evolution going back to the well over and over to solve the same problem in similar ways, like Jonah Lehrer barfing out a thousand words of recycled New Yorker fluff? You betcha.

For starters, there are animal wings. Bats, birds and prehistoric flying dinosaurs don’t have a lot in common — except that they all learned to fly, and grew their own appendages to do so. But in shape and structure, all those wings are different; the adaptations they made were in response to the same need for flight, but unique to the type of animal yearning for air time.

There are plenty of other instances of convergent evolution, too. Like eye structures in vertebrates versus squid, or echolocation in bats and dolphins, or fruit production in a variety of plants. It also happens at the molecular level — some enzymes converge on similar configurations of active site pockets, and some specific DNA and amino acid changes have been found (in the case of sonar-using bats and dolphins) to have occurred in separate species, independently helping to enable the same biological function.

Seriously, that level of convergence is straight-up crazy. Mother Nature goes completely off the rails sometimes. I really think the old girl should switch to decaf.

Actual Science:
University of Texas, AustinConvergent evolution
University of California Museum of PaleontologyVertebrate flight: the three solutions to flight
ScienceDailyGenetic similarities between bats and dolphins discovered
ExtremeTechScientists unravel the genetic secrets of caffeine’s evolution in coffee

Image sources: Mr. Kubuske’s blog (wings, wings, wings!), FlippySpoon (Rocky the flying squirrel), The Ultimate Gamer (Mario the flying Italian plumber), Spoonful (crazy-Lee Mother Nature)

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· Categories: Biology, Genetics
What I’ve Learned:

The punctuated equilibrium of Tatiana Maslany in Orphan Black
“Properly-punctuated equilibrium: Ten million ellipses, then a whole bunch of exclamation points.”

Punctuated equilibrium sounds like something you get when you perforate an eardrum. Like there should be PSAs about it, with scary pictures of death metal bands and Beats headphones with blood on the cans.

Luckily, it’s not that. No one’s coming to tear the Dethklok from your cold, deaf hands.

Instead, punctuated equilibrium is an evolutionary biology concept that made a big splash in the 1970s. It’s been desplashed a little since then, but it’s still pretty important. Plus Stephen Jay Gould helped think it up, and mostly everybody liked him. So there’s that.

The idea is this: in (at least) some cases, the pressure on organisms to evolve and adapt and squirt out a bunch of funky new species isn’t constant over time. When there’s plenty of food and the water is fine and everybody owns their own TiVo, then it doesn’t matter much if your individual set of genes makes you three percent hardier than your neighbor.

Oh, sure, you might get off your deoxyribonucleic ass and mutate up another leg or some gills or an enzyme to digest styrofoam. But let’s face it: you’ve got a pizza coming, and you’re still catching up on last season’s Orphan Black. Who has the time to speciate? And frankly, why bother?

This could go on for millions, or tens of millions of years.

(Well, Orphan Black won’t, of course. Tatiana Maslany is terrific and all, but she’s going to be too old for this thing at some point. I don’t care how many gills she grows.)

Things get interesting, says punctuated equilibrium, when the going gets tough. If the resources dry up, individuals die out. Small groups get separated from others; exploitable niches become more important. The quickest — and perhaps most radical — to adapt will ultimately thrive. Like the guy who brings a flask to the keg party, in case the beer runs out.

Or something less alcoholic. If you must.

It’s during these periods of ecological pressure and isolation that many new species are born. In between, all the old fern and finch and crocodile species sit around getting fat on Cheetos. And often each other.

But introduce a little hardship, and nature blossoms with adaptation to take advantage. That’s why an oceanful of brine shrimp will remain boring dumb brine shrimp forever. They want for nothing; they’re little trust fund crustaceans, born with silver… um, tiny handled eating utensils that rich baby shrimps would use… in their mouths.

(Or gills. Or whatever. Look, there’s no “aquatic face anatomy” tag on this post, all right? You get the idea.)

However! Scoop a small colony of shrimp out of the sea, stuff them in an envelope and shove them in the mail — now that’s an ecological challenge. And it’s enough to turn them into a whole new species: Sea Monkeys, with legs and fingers and brains and disturbingly human lips and what appear to be testicles growing on stalks out the tops of their heads.

And how does it work? Through the science of punctuated equilibrium.

So far as you know, unless you happen to own any of Stephen Jay Gould’s work. Or a freshman biology book. Or Sea Monkeys.

Stupid Sea Monkeys.

Actual Science:
Princeton UniversityPunctuated equilibrium
Evolution 101 / BerkeleyMore on punctuated equilibrium
National Center for Science EducationThe origin of species by punctuated equilibria
Shaking the Tree / Google BooksPunctuated equilibrium comes of age
Astrobiology MagazineLife after catastrophe

Image sources: BioNinja (evolution models), NeatoShop (poorly punctuated), BioNinja, The Mary Sue, io9 and Huffington Post (Tatiana Maslany clone evolution), She’s Fantastic! (Sea Monkeys)

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