Now it’s time to say good night,
Good night, sleep tight;
Now the sun turns out his light,
Good night, sleep tight.
Dream sweet dreams for me—
Dream sweet dreams for you.
Good Night
August 12, 2016 • 6:00 pm
Srsly, BBC?
August 12, 2016 • 2:30 pm
by Grania
After reading Jerry’s post on the putative oldest living vertebrate earlier today, I wondered what the teeth of the Greenland shark looked like and went to Google to see if I could find out. I ended up on the BBC’s shark pages and then went down the inevitable Internet rabbit hole of clicking through on other interesting pages.
The BBC is of course the bastion of plummy accents, perfect enunciation, and I would have assumed the best example of English as she is goodly spoken. Or not, in the case if the entry for the Frilled Shark.
The ex-teacher in me has a hard time reading bad writing on professional websites. I know from bitter personal experience that the more I re-read a piece of writing to eliminate any errors, the more likely I am to spot the mistake 5 minutes after I hit the Publish button. So I have some sympathy. Just not much when the very first sentence not only has a common homophonic error, but also manages to say the exact opposite of what the writer was aiming for.
Oy. Also, the exclamation marks!!! I did learn something new about sharks though, so I’ve got that going for me, which is nice.
On that note, happy Friday to all. I’m off to have a beer.
University of Texas threatens professors who ban guns in their classrooms
August 12, 2016 • 1:30 pm
As I’ve mentioned before, on August 1 a Texas law went into effect that allows students at four-year colleges to carry concealed handguns nearly everywhere on campus. (In exactly a year the same law will apply to two-year colleges.)
My post described the law like this:
The students need permits for their concealed carry, and the campus is allowed to designate a limited number of “sensitive areas” where guns aren’t allowed, though those areas must be approved by the institution’s board of regents. You’re also not allowed to store weapons in automobiles.
I can only imagine what more enlightened countries, like Canada, France, or England, think of such a law.
As far as I understand it, the law applies to all colleges, not just public ones, and replaces a previous law that allowed guns only in public areas of universities (quads, sidewalks, and the like). Private universities, however, can opt out of this law, and schools like Rice and Baylor have done just that. There’s no opting-out for state-funded schools.
Three professors at the University of Texas at Austin, Jennifer Lynn Glass, a professor of sociology, Lisa Moore, a professor of English, and Mia Carter, an associate professor of English, sued to block the law on the grounds that it forces their university “to impose ‘overly-solicitous, dangerously-experimental gun policies’ that violate the First and Second Amendments, as well as the Fourteenth (see today’s Hili dialogue). You can see the full copy of their lawsuit here.
I posted even earlier that the physicist and Nobel Laureate Steve Weinberg, also at the University of Texas at Austin, said that he would not allow guns in his classroom, and would take the consequences for violating the law. I haven’t heard about Weinberg since then, and he wasn’t party to the lawsuit.
Now, according to the Dallas News, both the state and the University of Texas have warned that professors defying this law, as Weinberg said he’d do, will face punishment:
“Faculty members are aware that state law provides that guns can be carried on campus, and that the president has not made a rule excluding them from classrooms,” attorneys representing the University of Texas at Austin and Attorney General Ken Paxton wrote in a legal brief filed Monday. “As a result, any individual professor who attempts to establish such prohibition is subject to discipline.”
This threat was clearly intended as a warning to the three brave women standing up against this insane law, but they’re persisting in their suit:
The state’s lawyers, in their Monday filing, asked Judge Lee Yeakel to throw out the professors’ lawsuit. The educators fired back in their own brief, calling again for Yeakel to halt the law for one semester so they can hold a public trial on whether campus carry violates their constitutional rights to free speech and equal protection.
The professors’ lawyers say the law and UT’s own campus carry rules are too vague for his clients to know if and how they might be punished if they tried to keep gun owners out of their classrooms.
“No person of common intelligence — and one would think that the tenured plaintiffs rise at least to that level — can figure out what governs them on this issue under Texas law and UT policies,” the professors’ attorneys wrote.
They go on to say there is nothing in state law or UT policy that explicitly forbids professors to ban guns in classrooms, so, then, the question is “whether there is any policy at all that would bar plaintiffs from doing what they want to do or that would punish them in some way if they did so.”
I suppose the President of UT Austin, Gregory Fenves, didn’t have much choice here, but it would have been nice to hear him say something like this: “We have to follow the law on this campus, but I think it’s a bad law and I accept it unwillingly.” But not only did he not say that, but also failed to exercise his power to turn any classrooms into gun-free zones.
In the state’s brief, attorneys from Paxton’s agency say the law is clear. It gives campus presidents the ability to designate each school’s limited “gun-free zones,” they say, and if classrooms are not expressly included in campus policy as off-limits to firearms, then guns must be allowed there.
“The president is the sole individual authorized to establish gun exclusion zones on UT Austin’s campus. He has not designated classrooms as gun exclusion zones,” they wrote.
A judge will decide the lawsuit next week, but, as I predicted earlier, I doubt the three women will prevail. It’s Texas, Jake!
And I’m glad I don’t have to teach at the University of Texas! Imagine an angry student confronting you about his grade. “Does he have a gun?” would be your first thought.
What should people know about your field to be considered “educated”?
August 12, 2016 • 10:30 am
I’m reading Sean Carroll’s new book, The Big Picture (it’s very good; I’ll provide a review when I’m done), and once again I got balled up about the difference between Einstein’s General Theory of Relativity and his Special Theory of Relativity. I can never get them straight, no matter how many times I look them up—just like I used to confuse the historical difference between Sunni and Shia Islam (I can now remember that one).
When I got confused this time, I thought, “Maybe a physicist would consider this difference something that every educated person should know.” And then I thought, “What would I want every educated person to know about my own area of study—evolution?” Well, there’s a lot I’d like people to know, like what the evidence is for evolution (that’s why I wrote WEIT), but if I had to summarize what I’d want people to know in just one paragraph, I suppose I’d say something like this. (Nit-pickers: I wrote this in a few minutes and haven’t gone over it obsessively.)
There are five parts to the “Darwinian theory of evolution”. First, evolution happens: that is, populations are genetically transformed over time. That means that the genetic constitution of a population changes from one generation to the next, not that individuals themselves change genetically. Second, that change of populations is gradual: substantial evolutionary transformation, like the evolution of bony fish into amphibians, takes thousands to millions of years. Third, evolution involves more than just transformation of populations, but splitting of populations—what we call “speciation.” One lineage can divide into two or more lineages that can’t exchange genes with each other; and those new lineages can themselves split. This produced the “tree of life” that, starting with one ancestral species about 4 billion years ago, produced the millions of species living today as well as the millions that have gone extinct without issue. Fourth, if you look at the splitting process in reverse, starting with any two twigs (species) on the evolutionary tree, you can, if you go back in time, find a common ancestor those species, just as if you take any two twigs on a tree and move down, you’ll find a common branch or node that they share. All living things are thus related, and the more recently their common ancestor lived, the more closely related they are (that’s the definition of “closely related”). Finally, the “designoid” features of organisms—the features that make them look so well adapted to their environments and lifestyles—are the product of natural selection: the combination of a random process, mutation, that generates genetic variation without regard to whether it’s “useful” or not, and a deterministic process, selection, that winnows the variation by retaining those mutations that are better able to make copies of themselves and eliminating the worse copiers. There are other important processes of evolutionary change, like random genetic drift, but only selection can produce the design-like features that so excite our wonder. And we have strong evidence for every one of these assertions, so that the “theory” of evolution is “true” not only in the sense that it’s the best explanation we have for how life changed on Earth, but also because we have copious evidence from many areas of biology supporting all five contentions.
That’s pretty much the way Darwin laid out the theory, though of course he knew nothing about genetics or “random” mutations. And, by and large, these propositions still stand up today. There are some exceptions of course: the origins of mitochondria in cells didn’t involve just gradual change of a single species, but the integration of one species with another, somewhat blurring the “treeness” of life. We also know a lot more about the process now than we did when Darwin limned it in 1859. But the paragraph above is what I’d expect anyone who considers themselves educated to know about evolution.
Not all readers are academics, of course, but most of you have fields in which you work and, presumably, would like others to know what’s important about that field. If you feel so inclined, write a sentence or paragraph about your “area”, and what people should know about it to be considered “educated.” If there’s too much to say, just pick out one thing to highlight—perhaps a fact or misconception.
The oldest living vertebrates? Greenland sharks could live 300-500 years
August 12, 2016 • 8:45 am
The Greenland shark (Somniosus microcephalus), a little known species, rivals the white shark in size. According to Wikipedia, individuals can be as long as 7.3 m (24 ft) and weigh more than 1,400 kg (3,100 lb). Here’s what they look like:
They are mostly fish-eaters, swim slowly for a shark, and live in the area below:
They have poisonous flesh, laced with neurotoxins that aren’t lethal to humans but can make sled dogs temporarily unable to stand. Although they’re carnivores, they haven’t been reported to attack humans. They do, however, eat large animals, though perhaps only after the animals are dead. As Wikipedia notes:
Greenland sharks are some of the slowest-swimming sharks, which attain a maximum swimming speed about half the maximum swimming speed of a typical seal. Therefore, biologists have wondered how the sharks are able to prey on the seals. Greenland sharks apparently search out seals and ambush them while they sleep. Greenland sharks have also been found with remains of polar bear, horses, moose, and reindeer (in one case an entire reindeer body) in their stomachs. The Greenland shark is also known to be a scavenger, but to what extent carrion (almost certainly the origin of the reindeer) figures into the slow-moving fish’s stomach contents is unknown. It is known that the species is attracted by the smell of rotting meat in the water.
The other day I saw some click-baitish post about this shark saying: “This shark eats polar bears!” They didn’t mention that the bears might already have been dead.
It’s been reported from mark-release-recapture studies that the sharks grow only about 1 cm per year (due, no doubt, to their cold habitat), so their large size suggested to some scientists that they might be very old. This suggestion was supported by a new paper in Science by Julius Nielsen et al. (reference below, access probably not free). Using a unique method of dating these sharks, they found that they could be up to 500 years old, attaining sexual maturity only after 150 years. That makes them the longest-lived vertebrate on record, far longer-lived than the previous recordholders, Aldabra tortoises and bowhead whales—a bit more than 200 years each. (See the bottom for the longest lived animals that we know about.)
The way that Nielsen et al. aged the sharks (they sampled 28 females between 2011 and 2013) was to use radiocarbon dating on the proteins in the eye nucleus, whose center forms when the shark is still a fetus. (Note: the sharks weren’t killed for this study: they were “by-catch”, accidentally caught in fishing nets.)
It turns out that nuclear bomb testing in the 1950s and 1960s created a spike in radioactive carbon (carbon 14) that was absorbed into the marine environment, and then into animal proteins, so you can see a spike in the amount of radioactive carbon occurring in specimens caught beginning around 1960 (figure from the paper):
The authors found that the highest amounts of radioactive carbon were found in the eye nuclei of smallest sharks, which were presumably born about 50 years ago. They also did radiometric dating of the eye nuclei of the other sharks, which were born before the pulse and could be dated using conventional methods. Because once the eye nuclei are formed in utero the proteins (and the carbon they contain, derived from the environment at that time) do not change further, forming in effect, biological artifacts that can be dated just like ancient wooden artifacts.
The analysis was a bit more complicated than this, but you can read the paper and its references for details. The upshot is that there’s opportunity for error—not only in the radiocarbon dating itself, but in their use of Bayesian statistics, which requires prior assumptions about age and growth rate.
Given this, the authors are still confident that their estimates are pretty accurate within the error limits shown. The figures that everyone wants to know are in bold (my emphasis):
The model estimated asymptotical total length to be 546 ± 42 cm (mean ± SD), a size matching the largest records for Greenland sharks, and the age estimates (reported as midpoint and extent of the 95.4% probability range) of the two largest Greenland sharks to be 335 ± 75 years (no. 27, 493 cm) and 392 ± 120 years (no. 28, 502 cm). Moreover, because females are reported to reach sexual maturity at lengths >400 cm , the corresponding age would be at least 156 ± 22 years (no. 19, 392 cm) (table S2). Amodel was 109.6%, demonstrating that samples are in good internal agreement, implying that the age estimates are reliable.
The error limits put the upper age limit of the biggest shark as 512 years and the lower limit at 272 years, with the point estimate at 392 years. That means the shark was estimated to have been born in 1624, and could have been born as early as 1504 (that’s 60 years before Shakespeare was baptized). The Guardian says this about the point estimate of the oldest female:
But not everyone is convinced that Greenland sharks can live for four centuries. “I am convinced by the idea of there being long lifespans for these kinds of sharks, [but] I take the absolute numbers with a pinch of salt,” said Clive Trueman, associate professor in marine ecology at the University of Southampton.
Trueman agrees that it is possible to get a record of the early life of a vertebrate from eye lens proteins. However, the fact that the proteins in the centre of the eye lenses, and hence the carbon-14 within them, came from nutrients taken in by the shark’s mother adds a number of uncertainties to the calculations, he says.
Campana says while the approach taken by the researchers is sound, he remains unconvinced that Greenland sharks live for almost 400 years. But, he adds, “future research should be able to nail the age down with greater certainty.”
2.) Is this the longest lived animal? No, not by a long shot. Sponges and corals, which are animals, can live millennia, with some Antarctic sponges estimated at 10,000 years old. However, for animals we’re more familiar with, the record longevity known with reasonable certainty is held by a clam. As I mentioned in 2013, a specimen of the ocean quahog Arctica islandica—a clam nicknamed “Ming”—was snatched from the sea floor off Iceland and dated at 507 years old using growth rings. Pity that the heartless scientists killed it, for who knows how long it might have lived? Like the shark above, this is a cold-water organism. Cold environments can put physiological limits on growth rates by slowing down metabolism, and that might have something to do with extreme longevity. Who knows?
To close, here’s an email exchange I had with Matthew about this paper:
Matthew: And why don’t most vertebrates live for a long time anyway, Mr Professor?
Me: Antagonistic pleiotropy? How the hell do I know?
Matthew: He he. The more you know, the more you realise we know nothing about anything.
Me: Nothing about anything? Not how many hydrogen atoms in a normal water molecule? Not when we split off from the ancestors of chimps? Not how old the universe or the Earth are?
Matthew: You know what I mean. Don’t be a curmudgeon
h/t: Hempenstein
______________
J. Nielsen et al. 2016. Eye lens radiocarbon reveals centuries of longevity in the Greenland shark (Somniosus microcephalus). Science 353:702-704
Readers’ wildlife photos
August 12, 2016 • 7:30 am
Reader Nicholas Arand sent a sequence that he called “Natural selection in progress”. Trigger warning: death of a zebra. His notes:
I am sending you an amazing sequence of pictures I took some 6 years ago in a trip to the Pilanesberg National Park in South Africa.
It was about 06:00 am, so the lighting condition was not great: that’s why the action photos are very blurry. In any case we were amazingly lucky to be there to watch two lionesses successfully hunting down a Zebra. Our guide, who was driving tourists thought the park almost every day for about 5 years, told us he had never seen a successful hunt before.
There was a group of zebras in the left side of our road and we could spot one lioness observing the group. The other lioness was in the other side of the road, just laying down.
The first lion starts chasing this very fat Zebra (according to the guide she was surely pregnant), it crosses the road just in front of us, and the second lions just traps her. Amazing coordination between the two of them.
‘
Good morning, Dobrzyn!
August 12, 2016 • 7:05 am
The haters are out; this one from Australia (I’ve redacted the email and IP address, though he doesn’t deserve it):
LOL! He got it wrong, though. I’m a SECULAR kike!
I’ve never yet gotten one of these where the person had the guts to use their real name.
Friday: Hili dialogue
August 12, 2016 • 6:30 am
Okay, today I’m going to get the date right: it is August 12, 2016, and Friday in Poland. It’s not only World Elephant Day, devoted to appreciating these magnificent beasts, but also, if you’re so unlucky as to be a Scientologist, Sea Org Day, the organization where you get almost no pay and have to sign billion-year-contracts. As Wikipedia notes:
Sea Org Day is a special event for all Sea Organization members, with rank and rating promotion ceremonies. It has been alleged by former members that recreational Sea Org Day events are mandatory: one ex-Scientologist claims “the one day a year you are supposed to get the day off, you are made to go on a bus to the beach, be there for roll call, participate in group games, etc.”
On this day in 1883, the last living quagga expired at the Artis Magistra zoo in Amsterdam. And, in 1944, the weeklong Wola Massacre ended in Warsaw, in which Nazi soldiers, on Himmler’s orders, indiscriminately killed between 40,000 and 50,000 Polish civilians and resistance fighters in retaliation for the Warsaw Uprising (different from the Warsaw Ghetto uprising). Nobody was ever prosecuted for this crime. The city of Warsaw was then destroyed.
On this day in 1887, physicist and roué Erwin Schrödinger, butt of a thousand Internet cat cartoons, was born in Vienna. His wave collapsed for good in 1961. And on August 12, 1990, the great cartoonist Bernard Kliban (known to all of us as B. Kliban), died of an embolism at 55. His bizarre cartoons often featured cats, like this one:
Meanwhile in Dobrzyn, Hili (who hates Leon), dismisses his rival’s talents:
Hili: Apparently there are cats who like travel by car.A: Yes, Leon loves it.Hili: Oh well, there are cats and there are cats.
In Polish:
Hili: Podobno są koty, które lubią jeździć samochodem.
Ja: Są, Leon to uwielbia.
Hili: No tak, koty są różne.
And out in Winnipeg, Gus decorates himself by lying amidst the flowers. I can’t help but think he realized that this would make a nice photo:
