Richard Leakey, son of Mary and Louis Leakey, is a deservedly famous paleoanthropologist who has contributed significantly to our understanding of human evolution. In a recent interview he expressed his confidence that skepticism over evolutionary theory will fade away over the next 15-30 years. He is quoted as saying:

“If you get to the stage where you can persuade people on the evidence, that it’s solid, that we are all African, that color is superficial, that stages of development of culture are all interactive,” Leakey says, “then I think we have a chance of a world that will respond better to global challenges.”

While I hope this is true, I am not as optimistic. I think the primary problem with his argument is the premise that you can get to the stage, “where you can persuade people on the evidence.”  In my opinion the evidence indicates that for many people, you cannot persuade them on the evidence. Unfortunately, human psychology simply does not work that way.

I agree with his premise that the evidence for evolution as a fact is overwhelming. In fact, I think we are already there. We do not need to wait 15-30 years for the evidence to be solid and convincing. There is a confluence of evidence from genetics, paleontology, anatomy, and developmental biology that has only one scientific explanation – common ancestry and organic evolution. We’re still working out the details, but the big picture is crystal clear.

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Many teachers are panicking over AI (artificial intelligence), and for good reason. This goes beyond students using AI to cheat on their homework or write their essays for them. If you have AI essentially think for you, then you will not learn to think. On the other hand optimists point out that AI can be a powerful tool to aid in learning. It all comes down to how we use, regulate, and manage our AI tools.

The cautionary approach was captured well, I think, by Mark Crislip in this SBM commentary, in which worries about the effects of AI on doctor education. How will a new generation of physicians learn how to think like expert clinicians if they can have AIs do all their clinical thinking for them? My question is – is AI fundamentally different than all the other technological advances that have come before. Did calculators take away our ability to do math? The answer appears to be no. Students still gain basic math skills at the same rate with or without access to calculators. But there are lots of confounding factors here, and so some teachers still warn of allowing kids access to calculators too soon. Others point out that access to calculators has simply shifted our math abilities, away from basic operations toward more modeling, problem solving, and complex concepts. It seems we are in the middle of the same exact conversation about AI.

We can also think about things like GPS. My ability to navigate from point A to point B without GPS, or to navigate with maps, has definitely declined. But using GPS has also made my navigating to unfamiliar locations easier and more efficient. I would not want to go back to a world without it.

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It is a useful exercise to think about the way millions or even billions of people behave to look for low-hanging fruit in terms of increased energy efficiency or environmental sustainability. While this should be a purely evidence-based and cost vs benefit exercise, it has unfortunately been sucked into the ever-growing culture war (at least in the US). Plastic straws are a great example of this. We use them mostly by habit and culture. They are often given, for example, by default in restaurants. As a result an estimated 8.3 billion plastic straws pollute the beaches of the world. Most people don’t need or even want straws, so it is a simple change to make them on-demand, rather than automatic. Further, paper straw technology is sufficient to replace them with a more biodegradable option. We can argue about the best way to achieve the goal of limiting plastic straw waste, and whether outright bans are necessary, but the plastic straw has now become an icon on the right about overreach on the left. Ugh.

It’s possible that e-mail may follow the path of plastic straws into a senseless culture war. According to the BBC, the Financial Times reports that the UK government is considering recommending that everyone try to send fewer e-mails. Why? Climate change.

“It claimed that if every British person sent one fewer thank you email a day, it would save 16,433 tonnes of carbon a year, equivalent to tens of thousands of flights to Europe.”

That sounds like a lot of carbon, but of course it is tiny compared to total carbon output – about 0.0037% of the output of the UK economy. This illustrates a few principles worth pointing out. First, when hundreds of millions or billions of people engage even in a small behavior, the cumulative effect adds up. So shaving tiny costs (in resources, in pollution, etc.) can have a measurable effect. But obviously the effect is going to be proportional to the action. I probably look at a couple hundred e-mails per day. Not sending one “thank you” e-mail seems like a drop in the bucket – because it is. The result is that the absolute magnitude is large, because there are hundreds of  millions of buckets, but the relative magnitude is small.

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A new review of the published literature regarding the ketogenic diet and intermittent fasting has, from my perspective, entirely predictable results. By this I mean they are consistent with previous dieting research and there are no surprises. They are also consistent with one of the major themes of this blog – you cannot get away from fundamental realities by making cosmetic changes. You cannot change the laws of physics or the nature of biology. This often translates to the fact that, as a general rule, there are rarely easy or simple answers to complex problems.

When it comes to dieting, researchers generally focus on several basic outcomes – weight maintenance, heart health, and glucose metabolism. You can also look at overall health outcomes, such as the risk of death over time. In terms of weight, there is only one factor that seems to matter – calories in vs calories out. This is the unavoidable reality, and there does not seem to be a way to game the system to significantly alter this equation. Proponents of special diets will argue that varying the proportion of macronutrients (fat, protein, and sugars) can affect metabolism. Some ironically argue that their recommended macronutrient balance will make metabolism “more efficient”. This is not necessarily a good thing when it comes to weight, however. Efficiency could mean getting more use out of fewer calories. If you want to waste energy (i.e. fat) you want to be inefficient.

But the bottom line of decades of research is that any effect of diets that vary macronutrient ratios on metabolism seem to have an insignificant effect on weight. You simply cannot get away from the massive factor of calories in vs calories out by slightly tweaking metabolism.

What does this current review show? Exactly that. First they find, as with most prior research, that the two diets do result in short-term weight loss. Pretty much all diets do. However, they also found that long term research (meaning up to 12 months) show that any short term advantage is lost and not sustainable. Since the goal of weight management is long term control, a short term reversible and small advantage does not contribute to this goal. It may, in fact, backfire. It is a distraction from effective long term behavioral changes. And some studies show that the rebound weight gain is greater. The review also concludes that any short term weight loss may be due to simply reducing calories, not any metabolic change. That is still the overall conclusion of the totality of dieting research – that any observed weight loss is due to reduced calories and not some other factor.

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The line between news and commentary has arguably become more blurred in recent decades. This has implications for libel law, which also reflects the shifting media landscape. A recent lawsuit involving Tucker Carlson illustrates the problem.

Carlson is being sued for defamation by Karen McDougal for a segment in which she claims Carlson accused her of extortion.  She is one of two women that we know of who were paid off to remain silent about affairs with Trump. Here is the money quote from Carlson:

“Two women approached Donald Trump and threatened to ruin his career and humiliate his family if he doesn’t give them money. Now that sounds like a classic case of extortion.”

For background, libel cases are hard to prove in the US. You need to demonstrate that statements were made in public that are claims to facts, that are factually wrong, where the person making the statement knew they were wrong or had a disregard for the truth, that there was malice of intent, and that actual harm resulted. For some statements you don’t have to prove harm, they are “libel per se,” such as accusing someone of pedophilia. The harm is taken for granted. If the target of the alleged defamation is a public figure, then the burden of proof is even higher.

At issue here are whether Carlson’s statements were presented as facts or opinion. Opinion is completely protected free speech, and cannot be defamatory legally. The first part of Carlson’s statement above is stated as simple fact. The second part (“that sounds like”) seems to be his analysis or opinion. Forgetting the other aspects of the defamation standard for now, this question seems to be the crux of the case. Was Carlson making a factual claim he knew to be untrue, or without concern for whether or not it was true? The defamation standard requires more than just being wrong.

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A new study takes another look at partisan motivated reasoning, with surprising (sort of) results. The study shows that as interested critical thinkers, we need to keep up with the psychological research about critical thinking.

First some background – motivated reasoning refers to the tendency to rationalize a defense of a position that we hold with some emotional investment, and reject counter-evidence. If a certain belief is part of our tribal identity, or has emotional significance, we react differently to relevant facts than when a belief is emotionally neutral. For neutral beliefs, we happily update what we believe when new credible information is presented to us. I don’t really care if Thomas Edison invented the light bulb or stole part of the design from Joseph Swan (he did, but he made important improvements also) – whatever the historical data says, I will happily believe. But if someone claimed that George Washington really wanted to be made king of America but was forced to accept a lesser role (he didn’t, I just made that up), I might be motivated to push back just out of patriotism.

Psychologists have been studying this phenomenon for years, and are discovering that it is a real thing, but it’s complicated (that should be no surprise). There is a general challenge with psychological studies that human behavior is complex and opaque, and they resort to using constructs and markers to reveal specific phenomena. How do you test motivated reasoning? First you have to separate people into groups based on some feature that should impact their motivation, such as ideology, religion, or political affiliation. Then challenge their beliefs and see how they respond.

Many studies have shown that when you do this, ideology matters. There is even a possible backlash effect, where motivated believers dig in their heels, but this effect is controversial and may be very small.

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It has rapidly become conventional wisdom that the widespread use of social media has resulting in an increase in the “echochamber effect.” This results from people only consuming media that already is in line with their existing beliefs and ideology. This is nothing new, psychologists have long documented that people are much more likely to access information that reinforces their existing beliefs and biases, and much less likely to engage with information that directly challenges their beliefs.

One of the hopes of the internet is that it would help people break out of their self-imposed echochambers of thought, by making a greater diversity of information, opinions, and perspective a mouse click away. That dream was thwarted, however, by the real world. Social media giants, like YouTube and Facebook, trying to maximize their own traffic, developed algorithms that placed information in front of people that they were most likely to click – meaning the kind of information they are already consuming. Watch one video about dog shows, and you will find a helpful list of popular dog show videos on the right on your browser. The next thing you know your mild interest in dog shows becomes a fanatical obsession. OK, maybe not, but that is the concern – self-reinforcing algorithms will tend to have a radicalizing effect.

There are also clearly virtual networks on the web developed to function like echochambers. There are blogs and channels dedicated to one specific world view, or opinion on a specific topic. The site is curated to be friendly to those with the same view, who are welcomed as compatriots. If you disagree with the approved view of the site, you are a troll. Your comments are likely to be blocked and you may even be banned. Of course, people have the right to protect their sites from truly disruptive and counterproductive behavior, but what makes a troll is in the eye of the beholder.

There are also metasites that curate multiple other sites, as well as news items, that cater to one world view, whether it be a political faction, specific activism, or ideology.

Supporting this echochamber narrative is the fact that people are becoming more polarized, tribal, and emotional over time. People hold more negative views of their political opponents, and are less likely to think that, while they disagree, they have a valid perspective.

The hope of the internet seems to have backfired. Rather than bringing people together, the internet has facilitated people separating themselves into multi-layered factions. The web is tribalism on steroids.

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Newsweek, who has been following the story of Italian Neurosurgeon, Sergio Canavero, now reports: “Human Head Transplants Are About to Happen in China: But Where Are the Bodies Coming From?”

I have already discussed the scientific aspects of this claim. They are highly implausible and I doubt that such a transplant is about to happen at all. If it does I predict it will be a dismal failure, and ethically dubious. First, I have to reiterate, that it is far more accurate to call such a procedure a body transplant. The head donor will wake up with a new body. The body donor is, I suspect, dead.

There are three basic hurdles that need to be overcome in order to have a successful body transplant – the surgical attachment, suppression of rejection, and regeneration of the attached neurological tissue. Given that Canavero is a surgeon, I suspect he is excited about the first issue. He may think he has made some advances because he improved his technique for making the attachment. This was never, however, the primary hurdle.

We are already making great advances with organ transplantation and controlling rejection. However, this is still a huge issue. Donor and recipient have to be closely matched, and lifelong drugs are required. Still, the amount of tissue being transplanted here will be a challenge. It opens up, for the first time, the possible effects of tissue rejection on an entire brain. While this is a significant hurdle, our current treatments mean it is not necessarily a deal breaker (it might be, but research would be needed to see).

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Last year Facebook announced that it was partnering with several outside news agencies, the Associated Press, Snopes, ABC News, PolitiFact and FactCheck.org, to fact-check popular news articles and then provide a warning label for those articles on Facebook. How is that effort working out?

According to a recent survey, not so well. Yale researchers Rand and Pennycook found only tiny effects overall, and it’s possible there is a net negative effect from the warning labels. Some people just ignore the labels. Perhaps more significant, however, is the fact that fake news articles that were missed by the fact-checkers were more likely to be believed as real because they lacked the warning label. The fact-checkers could not possibly keep up with all the fake news, so they were overwhelmed and most of the dubious content not only made it through the filters, but benefited from a false implication of legitimacy.

Further, the Guardian reports that this arrangement between Facebook and these news outlets compromise the ability of those news outlets from being a proper watchdog on Facebook itself. If their journalists are being paid by Facebook to fact-check, then they have a conflict of interest when reporting on how Facebook is doing. This conflict is exacerbated by the fact that news organizations are hard-up for income, and could really use the extra income from Facebook.

So it seems that the fact-checking efforts of Facebook were insufficient to have any really benefit, and may have even backfired. Warning labels on dubious news articles may be the wrong approach. It’s simply too easy to foil this protection by overwhelming the system. You could even deliberately flood Facebook with outrageously fake news stories to serve as flack and provide cover for the propaganda you really want to get through. In the end the propaganda will be even more effective.

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In North America house sparrows are a menace. They are an invasive species introduced in the 19th century, and have established themselves as a large population. Unfortunately they do so by displacing many local species, such as blue birds. They are cavity nesters and will use up many of the prime nesting spots before migratory native birds get a chance. Their presence reduces the population of many native species.

Birders have a special disdain for house sparrows and European starlings (another invasive species). They are both a threat to bird biodiversity. They are also not protected by the Migratory Bird Treaty Act, which means it is legal to remove their nests and even to capture and euthanize them (you can then donate them to raptor refugees for food). Many birding enthusiasts recommend active measures to control house sparrows and minimize their impact on native species.

Partly for these reasons house sparrows are an ideal target for scientific research. They can be legally captured, and the research will then serve the extra added small benefit of removing house sparrows from the wild.

All of this makes it all the more ironic that PETA has chosen to target a young researcher (a post-doc) for harassment due to her research on house sparrows. Really, PETA, you have chosen the wrong subject to defend, the pests of the birding world.

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