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No neurogenesis in adults?

March 9, 2018

A new study of adult brains finds zero evidence for young neurons in adults. In adult humans. Adults of other species, canaries and macaques, seem to experience neurogenesis. (Cite.) But, other studies using different approaches have found some evidence for it. Perhaps some of the experimentalists are mistaken in their practice or technique. A more interesting possibility is that there is some interesting and unknown biology happening, causing some of those approaches to show something, something not yet well understood. Science — and investigation generally — benefits from looking at same question from multiple directions. Ed Yong does a good job explaining how this piece of research conflicts with past clues, and how much uncertainty there still is on a basic question of neurophysiology.


Muscles and waves

March 8, 2018

Hafþór Júlíus Björnsson, who plays The Mountain on Game of Thrones, just set a world record of 1,041 pounds, in the deadlift.

Novelist Philip Alan retells the tragedy of the Royal George, which went down while anchored in a calm harbor in August, 1782, with 900 hands lost. Despite the valiant and futile efforts of the ship’s carpenter. An early etching of the loss is shown left. Alan then repeats a common — but I think wrong — explanation of why sailors then did not much swim:

Most contemporary sailors could not swim, because they chose not to learn for reasons that made perfect sense to them. It was an age still dominated by strong notions of fate, and few professions seem to have been more fatalistic than sailors.

The assumption there is that most sailors of that time actually made a choice on the matter. As if swimming were an elective they refused during their high school curriculum, right after signing up for maritime studies. My own suspicion is that most sailors of the time exercised no choice in the matter at all. The reason most sailors then didn’t swim is that they came from a time and place when few children were taught to swim. I have seen no evidence that sailors had that skill any less than others of that time and social class. After they became sailors — that not always a matter of choice — they were busy and rarely had the opportunity then to learn. I agree that “any writer setting their work in the 18th century needs to try and get into the minds of their subjects.” It is even more important to understand their cultures. Individuals are wondrously varied. But none escape that.

The economic benefit of regulation

March 7, 2018

Unsurprisingly, some coal-powered utilities, recently required to examine local ground water, have discovered they have been tainting it with arsenic, radium, and other poisons. The Trump administration has a solution for this. They are rolling back the Obama regulations that require utilities to look at that. Knowledge can be a costly thing, when you are handling coal ash.

Of course, the side effects of contaminated water is costly to those who drink it and fish in it. Those costs are very real, whether they can be tied back to the cause or not. Economists call those costs externalities, because polluters take the profit, while others bear the burden. Regulations work when they make businesses lessen their externalities. When the cost reduction for others exceeds the regulation cost, there is a clear benefit to the economy. The OMB just released a report comparing the costs of federal regulations from 2006 to 2016, to the benefits of those regulations. In aggregate, they had a minimum benefit more than two and a half times their cost. A benefit measured in hundreds of billions of dollars. I suspect the Trump administration will want the OMB to stop looking at that.

Of course, we all know regulation might have other problems. They stifle innovation, right? Two conservative economists took a look at that question, and failed to find the correlation they were expecting. The scatterplot above shows zero correlation between which industries are more regulated and which exhibit more business dynamism. (Cite.) The journal Economic Policy should be congratulated, for publishing, indeed highlighting, a paper that has negative finding.

The economic benefit of environmental regulation isn’t some socialist pipedream. It is capitalist economics, that one can read from most any introductory text. The Trumpistas who deny it by rote are not practicing economics of any sort. They are simply ignoring the real costs of pollution, and politically dismissing those who bear it, and trumpeting the profits of polluting industries uber alles.

Hat tip to WFQ for some of these links.

Of turtles and whales

March 6, 2018

Kemp's Ridley sea turtleSea turtle conservation efforts seem to be working, worldwide. The Texas coastal bend is a key part of the Kemp ridley range. (Kemp ridley shown in photo.) Donna Shaver, head honcho at Padre Island for protecting these turtles (see photo), has been recognized for her work.

Alas, the situation is not so sanguine for the right whale, which is on the verge of extinction, and had no calves this season. Lobstermen are doing their part.

Abortion is safe

March 5, 2018

This needs to be repeated: abortion is safe. The author of that article seems to me too sanguine in explaining the cry otherwise as misunderstanding. Those morally opposed to abortion want to make it seem riskier than it is.

And new technology is making it safer, easier, and cheaper. That trend will continue.

There are reasons for late abortions. Nature is uncaring.

Pew data shows the expected relationship between views on abortion and religious belief. The notion that the earliest embryo deserves moral status requires some almost-magical view about what an embryo is or what goes into making it. But that poll shows some pleasant exceptions:

There are, however, cases where the views of a church’s members don’t align with its teachings on abortion. For instance, while the Roman Catholic Church is an outspoken critic of abortion, U.S. Catholics were divided on the issue in the 2014 survey, with 48% supportive of legal abortion and 47% opposed.

Many women who have abortions are conservative and pro-life. As with many things stereotyped, it feels different when the shoe is on your foot. Rebecca Traister takes on the right-wing narrative head on:

Forty years of anti-abortion forces aggressively applying the language of family, love, and morality to the embryo and the fetus, and rarely to the women who carry them, have forced women into a defensive crouch.

The scary thing about Republican Congressman Scott DesJarlais is not that his ex-wife and girlfriends have had abortions, but that he still is licensed to practice medicine. I hope that gets corrected.

The exodus of American Catholic youth

March 4, 2018


The religious press has quite a few stories, like this one, about a new study (not freely available) on the disaffiliation of American youth from Catholicism. Besides the large numbers, the interesting statistic is how young people are when they disaffiliate. “Seventy-four percent said they stopped identifying as Catholic between ages 10 and 20, with a median age of 13.” As the PEW data shows (see above), the trend encompasses protestant sects as well, with the sole exception of historically black protestant sects.

Looking back on my own youth, it was when I was in high school and starting to take a real interest in math and science that I saw we were being taught how to understand and investigate the world, in physics and biology classes, while also being taught what to believe on faith, where religion was involved. It became clear quickly that none of the adults teaching me religion had any basis for what they were teaching, but were just parroting what they had been taught. When I asked math teachers why something was so, they would show me a proof. When I asked a biology teacher a question, they showed me, and taught me to look and dissect. But religious teachers just mumbled explanations that any quick teen saw through.

I had a mixture of Catholic and protestant upbringing. There was an interesting difference in how they handled the role of reason. The Catholic Church teaches that its god can be known through reason, and though its theologians have contrived a variety of arguments, it does not make any of them part of its dogma. Which is wise, because then the belief the Church forwards would depend on that particular argument holding. Instead, the Church teaches — as a matter of faith! — that a reasoned approach is possible, without stating what that approach is. An amusing sophistry. Protestants typically just throw up a collection of bad arguments hoping that something sticks to the wall.

Teenagers are quite sensitive to adult hypocrisy. Today’s teens come armed not just with easy access to the criticisms of the apologetic arguments, but also intent on seeing whether the adult speaking actually hangs their own belief on what they are putting forward. There is a particular kind of dishonesty in giving an argument as the reason one’s listeners or pupils should believe, even when it isn’t the reason the speaker or teacher does so.

Longer telomeres

March 1, 2018

A recent paper with more authors than any should have shows that genetically longer telomeres are associated with several kinds of cancer, while short telomeres are associated with some other kinds of disease, non-neoplastic, such as heart disease. Of course, telomere length is not completely dependent on genes, and the genes that affect it also affect other things. The paper discusses that. Their conclusion still:

Our cancer findings are compatible with known biology. By limiting the proliferative potential of cells, telomere shortening may serve as a tumor suppressor, and individuals with longer telomeres may be more likely to acquire somatic mutations owing to increased proliferative potential. .. The inverse associations observed for some non-neoplastic diseases may reflect the impact of telomere shortening on tissue degeneration and an evolutionary trade-off for greater resistance to cancer at the cost of greater susceptibility to degenerative diseases, particularly cardiovascular diseases.

I would say “pick your poison.” Except, we don’t get to choose.