Science Saturday: evolution in action, arctic methane and suboptimal teaching tactics

Teaching:

You mean we can’t do things like this anymore?

LIVINGSTON, Tenn. — A first-year teacher from Overton County may lose his job after writing the word “stupid” across a student’s forehead with permanent marker, a district official told WSMV-TV in Nashville.

The math teacher has been suspended indefinitely, Matt Eldridge, director of the Overton County Schools, told the NBC television station.

“We’re here to help the children and not to hurt them,” Eldridge said, adding “One word can break a child. I mean, I’ve got three children. I wouldn’t want it done to mine.”

The incident happened last week at Allons Elementary, where a student asked a question and the teacher responded by writing on the child’s forehead in front of his classmates, Eldridge told the TV station. The teacher also wrote the word “stupid” backward on the student’s forehead, so he’d be able to read it when he saw himself in the mirror, he said.

“The teacher said, ‘I was trying to joke with him,’ and of course, I said, ‘That’s not the way you joke with anyone,’” Eldridge said.

Oh well….I suppose that is a sub optimal method of teaching.

Global Warming and Climate Change
Here is one aspect of this: it is true that a certain percent of greenhouse gases that are being released to the atmosphere were not caused by human activity. But the warming caused by human activity is helping thaw the permafrost that had been keeping these gases from reaching the atmosphere (JUSTIN GILLIS, New York Times):

A bubble rose through a hole in the surface of a frozen lake. It popped, followed by another, and another, as if a pot were somehow boiling in the icy depths.

In an Alaskan lake, bubbles of methane, a potent greenhouse gas, collect beneath the ice. More Photos »

Every bursting bubble sent up a puff of methane, a powerful greenhouse gas generated beneath the lake from the decay of plant debris. These plants last saw the light of day 30,000 years ago and have been locked in a deep freeze — until now.

“That’s a hot spot,” declared Katey M. Walter Anthony, a leading scientist in studying the escape of methane. A few minutes later, she leaned perilously over the edge of the ice, plunging a bottle into the water to grab a gas sample.

It was another small clue for scientists struggling to understand one of the biggest looming mysteries about the future of the earth.

Experts have long known that northern lands were a storehouse of frozen carbon, locked up in the form of leaves, roots and other organic matter trapped in icy soil — a mix that, when thawed, can produce methane and carbon dioxide, gases that trap heat and warm the planet. But they have been stunned in recent years to realize just how much organic debris is there.

A recent estimate suggests that the perennially frozen ground known as permafrost, which underlies nearly a quarter of the Northern Hemisphere, contains twice as much carbon as the entire atmosphere. [...]

Evolution in Action
Jerry Coyne has an interesting article about lungfish and how they have a “near walk” though they stay in the water. In other words, perhaps the walking gait preceded walking:

The conventional wisdom about how our tetrapod ancestors invaded land (“tetrapods” are four-footed land animals that include birds, mammals, reptiles, and amphibians) was that the evolution of limbs with digits occurred about the same time as the the walking gait evolved, perhaps when a lobe-finned fish (“sarcopterygian”) like Tiktaalik began frequenting shallow waters. Those ancestors might have propped themselves up in the shallows, and eventually made forays onto land for food, creating selection pressures on both morphology and behavior to move about on the land. As this scenario goes, the typical land-animal leg with toes evolved along with the typical land-animal gait, which is an alternation of fore- and hindlimbs that push off the ground.

This scenario may have to be revised, though, in light of a new paper by Heather King and colleagues in the Proceedings of the National Academy of Sciences. What they found is that the closest living relative of tetrapods, the lungfish, seem to have a precursor of the alternating-limb gait and the ability to push off the ground, even though they don’t venture onto land. And this suggests that the common ancestor of lungfish and modern tetrapods, which lived about 400 million years ago, was “preadapted” or “exadapted” to walk. That is, that ancestor might have had its own adapted form of movement that could be co-opted for walking when its descendants invaded land. It’s a gait-first, limb-next hypothesis.

The post has a cool photo.

Adaptations by different mutations of the same gene
Here we have a case of three lizards which evolved white skin via different mutations of the same gene:

In the White Sands National Park of New Mexico, there are three species of small lizard that all share white complexions. In the dark soil of the surrounding landscapes, all three lizards wear coloured coats with an array of hues, stripes and spots. Colours would make them stand out like a beacon among the white sands so natural selection has bleached their skins. Within the last few thousand years, the lesser earless lizard, the eastern fence lizard and the little striped whiptail have all evolved white forms that camouflage beautifully among the white dunes.

Erica Bree Rosenblum from the University of Idaho has found that their white coats are the result of changes to the same gene, Mc1r. All of these adaptations arose independently of one another and all of them reduce the amount of the dark pigment, melanin, in the lizards’ skin. It’s a wonderful example of convergent evolution, where the same environmental demands push different species along the same evolutionary paths. But Rosenblum has also found that there are many ways to break a gene.

Each of the three lizards has a different mutation in their Mc1r gene, that has crippled it in diverse ways. These differences may seem slight, but they affect how dominant and widespread the white varieties are, and how likely they are to branch off into new species of their own. Even when different species converge on the same results – in this case, whitened skin – and even when the same gene is responsible, their evolutionary paths can still be very different.

A fun video: Orangutan uses a face cloth:

Note that in this state, the orangutan acts as the perfect Republican (doesn’t share his cloth with the other orangutan…)

Idiots: useful and not

Workout notes I had to attend graduation exercises so I ran early; I did my 5.2-5.3 mile course in 51:07. It was breezy, clear and 29 F. The first mile (10:20) was the slowest. My last mile was 9:50 (ok, these “miles” are slightly long). Still, while this was hardly a race effort, it was an effort and that is probably because I am not quite recovered yet.

Posts
The President talks about the Iraq draw-down.

More on Hitchens

Some might find this tribute article to be a bit harsh as it is written in a “roast” style, but it has a “dang, I loved the mean old bastard” quality to it.

Idiots: useful and not
Ron Wyden
Paul Krugman doesn’t think much of Ron Wyden’s collusion with Paul Ryan to end Medicare as we know it:

Sen. Ron Wyden did indeed do a bad, bad thing in his joint proposal with Paul Ryan. Ezra Klein explains why; and the devil isn’t in the details.

What Wyden did was to give cover to the fundamental fallacy of right-wing attempts to dismantle Medicare: the claim that market competition is the key to reducing health care costs. We have overwhelming evidence on this — and it just isn’t true. Looking both within the United States and across countries, if you ask which systems are best at cost control, the ranking looks like this:

Government provision as well as financing (socialized medicine) > single payer > market competition.

Krugman points out that the health care reform bill that he backed passing was indeed a private insurance bill, but that was because that was the best we could get, given this political climate. So why retreat from the public plan we have in place now?

Not Useful: Michelle Bachmann
Michelle Bachmann got her feelings hurt that Newt Gingrich called her out for “getting her facts wrong”; see at about 2:20 or so:

So, does Poltifact back her up? Check out the screen shot:

As you can see, many of her public claims are false. Of course, this is nothing new; she was well known for getting even basic stuff wrong. Here she talks about the “Hoot-Smalley” act that was “signed into law by President Roosevelt” (it was the Smoot-Hawley act that was signed into law by President Hoover)

Here you can see more of her more famous ridiculous assertions.

She reminds me of the C or D student who thinks that you are being unfair when you assign them the grade that they earned. She is a living example of the Dunning-Kruger effect.