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Cross-dressing hummingbirds

September 16, 2021

FemaleJacobinSeemingly, some fraction of young, female Jacobin hummingbirds sport the breeding plumage of males. Because male hummingbirds are quite aggressive, that provides the cross-dressed females some advantage to accessing food. It’s always a bit of a risk to make the leap from perceived advantage to thinking it was somehow selected. It will be interesting to see how the distribution of that attribute changes over time.

How to be green, redux

September 15, 2021

Auden Schendler correctly points out that the emphasis on individuals and corporations lowering their carbon footprint is not a solution to global warming, but rather, a distraction, fostered by the fossil fuel industry:

What do fossil fuel companies prefer? They like consumers and corporations to do anything and everything as long as they stay out of the companies’ way and avoid doing anything that could actually make a difference.

I explained much the same, a few years back. Everything else individuals do en masse matters much less than the politics they enable. An individual supporting politicians who raise fuel standards, close coal plants, and accelerate the shift away from internal combustion engines is doing more for the environment than one who doesn’t, even if the first drives a gas-guzzler and flies twice a week, while the latter bicycles everywhere.

Testing whether masks work

September 14, 2021

The evidence for the benefit of masking against Covid-19 has been fairly lukewarm. There is some evidence, not strong, that wearing masks may a bit reduce an individual’s risk of catching the disease. Which is the natural thing to study first.

That does not address the issue of whether masks slow community spread. Studies designed to look at individual benefit don’t measure that. By design. While any practice that lowers individual risk also should some lower community spread, if used widely, the converse is not the case. It is quite feasible that some practice might lower community spread, even though those who practice it see negligible benefit vis-a-vis those who don’t.

Which makes studying that difficult. There have been some observational studies. Such as one in Kansas, comparing counties with different masking policies. That showed benefit to public masking mandates. (Cite.) The problem is that observational studies always raise questions about what other differences there are between the communities compared, that might have caused the effect? It is easy to imagine all sorts of confounders, from income to geography to political orientation. Today, sadly, that last correlates with a variety of behavior related to disease transmission.

Randomization is a well-known solution to confounders, that highlights the putative cause in question. But how do you randomize at the community level?

Well, Yale researchers went to Bangladesh, and did that. They selected a set of study villages, and provided masking intervention to a subset chosen at random:

The latest finding is based on a randomized trial involving nearly 350,000 people across rural Bangladesh. The study’s authors found that surgical masks — but not cloth masks — reduced transmission of SARS-CoV-2 in villages where the research team distributed face masks and promoted their use. .. By randomizing entire villages, Gandhi says, the latest study improves the assessment of both mask adherence and community-level transmission.

(Cite, preprint.)

They saw a significant difference in Covid-19 spread, between the test and control villages. The 11% might seem modest on first read. It shouldn’t. That measures a wedge between two curves in time, after just a few weeks. Modelers will have to turn that into a rate as a function of degree of use, to estimate longer-term benefit. Surgical masks were more than twice as effective as cloth masks in the study.

I don’t know how often there have been randomized control trials where communities are the unit of study. Doing that requires significant resources, and a kind of intervention that can be done or not at the community level. Such studies can’t be blinded, in the sense that is applied to human subjects. The psychology and human interaction that makes that so important with human subjects isn’t so present with communities. It will be interesting to see how this work is viewed in retrospect, assuming it holds up to review. I will not be surprised if it spurs similar studies on other issues.

Portents?

September 13, 2021

RedBlueWill Wilkinson points out that rural America is no longer the hundreds of distinct cultures that it was not many decades past. He argues that it has been homogenized, and turned it into something new.

And something ugly. Mona Charen highlights Republican politicians calling for more violence to achieve their goals. That likely is tied to the delusional beliefs that now are integral to how they view their political identity:

Most Republicans also consider support for Trump — and his false claim to have won the 2020 election — to be an important part of their own partisan identity alongside support for conservative principles. About six in 10 say that supporting Trump, and that believing that he won in 2020, are at least a somewhat important part of what being a Republican means to them.

One might take hope in the fact that the metropolitan population is the only one that is growing. Except, that increases the modern Republican view that they are facing an existential threat against which any kind of action is justified.

Beware unnamed sources

September 8, 2021

I have seen efforts in quite a few places to downplay the investigations into Trump’s attempted coups, on the basis of a Reuter’s report in late August that the FBI had found that legal liability didn’t extend above the various bozos and dupes who actually stormed the Capitol. The article was based on claims made by “four current and former law enforcement officials.” Unnamed.

House Minority Leader Kevin McCarthy picked up on that, both the reporting and the effort. Causing Bennie Thompson and Liz Cheney, heads of the House investigation committee, to make inquiries with the federal departments concerned. Now we have named sources, with legitimate and known route of information, making an official statement:

When this anonymous report was first published, the Select Committee queried the Executive Branch agencies and congressional committees involved in the investigation. We’ve received answers and briefings from the relevant entities, and it’s been made clear to us that reports of such a conclusion are baseless.

Blood and vaccines

September 7, 2021

I have been a regular, whole blood donor for decades. Because I somehow never acquired some common viruses, my blood can be transfused to infants and other immuno-compromised patients. The blood banks care quite a bit about whether donors have had malaria or babesiosis or Chagas or quite a few other diseases. Or even if they recently have traveled to areas abroad, where some diseases are more prevalent.

Generally, the blood banks do not care whether donors have been vaccinated. I have donated several times soon after getting the flu shot. There is little reason to think that any residual antibodies are harmful to recipients. The smallpox vaccination is an exception: blood banks will bar someone soon after receiving that. The reason is that vaccine still uses a live virus. None of the Covid-19 vaccines use a live virus, and people who have had them can give blood. I have donated multiple times since receiving mine.

Alas, the talk radio and internet hotbeds of ignorance have been working overtime with regard to Covid-19 and vaccines. Some influenced by that are refusing blood, from fear that the donor was vaccinated. Which now is quite likely:

More than 90% of current donors have either been infected with covid or vaccinated against it, said Dr. Michael Busch, director of the Vitalant Research Institute, who is monitoring antibody levels in samples from the U.S. blood supply.

CovidSeroprevalenceBlood donors are an obvious group to study for such things, since their blood already is available and tested for a broad variety of qualities. A recent article shows the trends in Covid-19 seroconversion and vaccination among them, from which the graph right was taken. The authors anticipate similar trend in the broader population. There likely is some difference, since the donor population is far from a random sample.

While most blood available now in the US comes from vaccinated donors, that is not cause for worry. Those vaccinated may donate plasma, also.

JAMA recently published a statistical analysis of adverse events after the mRNA vaccines. Here is a rule of thumb: If your concerns about vaccine safety come from reading and understanding papers like that, or from listening to those who do and who use such sources as a basis for what they say, your concerns may be valid. Quite limited. But valid. If your concerns come from any other source, they most likely are bogus.

When I was young, I remember stories in novels and on television, where western physicians bring some remedy for a disease to a less developed part of the world, as the phrasing then went. Where the remedy was resisted. From superstitious notions tied to local folklore and religion. The physicians and their purpose would be subjected to fantastic tales. All this would be pushed by those influential in the local culture, ignorant about science, and disdaining western physicians who interject themselves into the local society. Those stories thus would contrast backwards, “pre-scientific” cultures with the modern world. Their endings spelled hope of what direction the world as a whole was moving.

Those modernist authors at the start of the atomic age were wrong, far too hopeful. Every failing they imagined about such cultures is present in our own times, in our own places, in our own culture, a half century later. The modern world never became scientific. Only parts of it. And in other parts lie every cultural feature that ever has resisted that.

The pill and cancer

September 2, 2021

OralContraceptivesAndCancerDr. Jen Gunter has an update on recent studies about the pill and cancer. While it is summed up in the chart right (click for full size), I recommend reading her analysis.

I also recommend that every young woman in Texas start making concrete connections to a city outside this state. Visit. Strengthen acquaintances. Learn the neighborhoods. Having an abortion typically is the furthest thing from one’s mind. Until it isn’t. Escaping the land of an authoritarian government is far from the mind of those who long have called it home. Until the need arises. So it is worth working on the question now: Where will I move if I need? Don’t make those next trips to Texas cities. Learn the lay of a free land. We can hope that things return to normal in the near future. There is no guarantee of that.

Neanderthal hunting camp?

September 1, 2021

I will remain skeptical that this 76,000 year-old site near Madrid was a real hunting camp, until the archaeologists figure out what kind of alcohol the hunters drank. (Cite.)

Ever so carefully…

August 31, 2021

WaymoTaxiWaymo is opening its automated taxis to a select set of beta customers in a small part of San Francisco, safety drivers still present, following the steps it set in Arizona. On the one hand, I want to cheer it for getting further than any automated vehicle company yet. Its taxis in Chandler are open to the public and have no safety driver. Now it is working on its second locale.

On the other hand, at the current pace of expansion, it will get to an area that interests me sometime in the 23rd century. Of course, S-shaped curves are flattish at the beginning, making it hard to predict when their ramp occurs.  I just want to see that ramp within my investment horizon. (Ob disclaimer: I’m still long Alphabet.)

Ivermectin

August 30, 2021

The arrival of Covid-19 spurred researchers to find which existing drugs might be useful against it. Early in vitro experiments showed some promise for ivermectin. The fact that it is commonly used against parasites and extensively in animals actually favors it, rather than being any kind of problem. 

The reason it didn’t gain much traction with physicians treating the disease is that it did not pan out in clinical trials. Which typically is the case. Finding good treatments for diseases is hard. Drugs that show early promise only rarely have real benefit. Recent news has two more strikes against it. The high quality study where it showed significant benefit turns out to be fraudulent. Meanwhile, a second high quality study, not yet published, will show no benefit at all. That is disappointing to the medical community, which always want more tools against any disease.

The good news, regarding Covid-19, is that other drugs have proved useful in treatment, and most importantly, that the vaccines continue to work well. Though vaccine efficacy against infection has dampened. It’s hard to suss the degree to which that is decline in acute immune response or a consequence of facing a tougher opponent in the more infectious delta variant. The vaccines continue to be very effective at preventing hospitalization and death: “During May 3–July 25, 2021, the overall age-adjusted vaccine effectiveness against hospitalization in New York was relatively stable (91.9%–95.3%). “ That means someone vaccinated is 12 times less likely to be hospitalized with Covid-19. That is the kind of odds one wants. How long that holds into the future, we have yet to see.

CovidMortalitySpikeIf your physician is not eager to prescribe ivermectin, and instead is urging you to get vaccinated, they are simply acting like a science nerd who is tracking the relevant studies and wanting to give their patients the best chance, given the data to date. As Zeynep Tufekci explains, that is tough to do in the midst of a new epidemic, as the disease, the treatments available, and the data on those all are in flux. It is impossible to do, for anyone who hasn’t studied statistics. 

If you’re suspicious that your physician, instead, is swayed by some nefarious forces intent on suppressing useful drugs, or that there is something nefarious behind the push to get people vaccinated, rather than the simple desire to save lives, you’re acting like someone who has fallen for the spiel of grifters. Those grifters work political alliances. They work religious alliances. Get smarter. 

The chart showing Covid-19’s mortality spike is from an article on the resultant decline in US life expectancy. That data is only through 2020. When data is available next year, that spike will look worse.