Comments by "EebstertheGreat" (@EebstertheGreat) on "Talks at Google" channel.

  1. It's approximately correct that for the most part, dosage scales across species not with body mass but body surface area (or the 2/3 power of the mass). The truth though is even more complicated, as typical power laws used to fit effective doses for many species have exponents between 0.5 and 1, typically around 0.75. Among humans, the dose for many drugs depends on body fat content, so dosage is often quoted in mg/kg, but that's still not strictly accurate. Linear scaling with mass certainly can't be used to extrapolate doses from a 70 kg human to a 5500 kg elephant.
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  2.  @musikSkool  I don't think it's similar. Consideration of caliber and gunpowder mass and such for hunting will depend on the ballistic details of the gun and the target. The stopping or killing potential will certainly depend on the animal, but it will depend on things like the density of the skin (zeroth power of mass), distance from skin to vital organs (<1/3 power of mass), blood volume (1st power), glucose stores (3/4 power), etc. So any details are going to be empirical and will vary from animal to animal even with similar size, especially if you compare between classes (e.g. rodents to songbirds). The answer isn't going to be easily found from first principles of biology, but better by trial and error. In the case of giving elephants cocaine for the first time, there is no empirical knowledge at all, and you can't just start giving them random doses. You start with an extremely low dose (in elephant terms) and gradually increase it. Unfortunately, it's not super easy to tell what a low dose "in elephant terms" is, and if you pick the wrong exponent, you can think you're starting with a safe, low dose, when you actually are giving quite a sizable amount. If true, that's what happened in the story from the video. But unlike with bullets, in this case, we have theoretical reasons to expect a particular scaling law, for the 2/3 power of mass, not the 1st power (though as I said, in practice it tends to be more like 3/4, for reasons that are mathematical and too long to get into). So a bit more knowledge might have saved the researchers a lot of pain.
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  3. nick p Legally speaking, evolution is required curriculum in every state as far as I know. However, in practice, it is not taught very well (and sometimes not at all) and not very important in standardized tests (so teachers can get away with not teaching it). There are many districts where teaching evolution might be considered more trouble than it's worth. Even when the teacher does understand it well (and does believe it), they are relying on textbooks with poor coverage at best, facing complaints from parents, facing students interrupting their class, and facing losing credibility with the kids in general.
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  4. TheRealArchAngel "Actually your required to go to school by law until you graduate in order to support the teacher unions while the Schools usually leave what the individual teachers actually teach up to the teachers so the quality of the classes and what the child learn does vary" Mandatory schooling is much older than teachers' unions, and every state has a required curriculum. Exactly how teachers present the material and what else they include in addition to the core does vary, but in theory, they are all supposed to teach certain minimum requirements in each subject at each grade level.
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  5. Siri I'm sure there's no state without any high schools that teach evolution well. The point is that these are states where many schools don't.
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  6.  @musikSkool  True, bore definitely doesn't scale linearly with the size of the target. Shooting a mouse with a BB gun, most of the energy is lost just getting through the tough skin, which is not as tough as a wildebeest's or whatever, but is not too far off the average for mammals. But if you're hunting an elephant, you don't really want to knock it down dead just like that anyway, because to do that, you really would need a pretty big boom. Not a cannon, granted, but still something bigger than the 2 bore elephant guns people used to break their wrists firing. You want the elephant to bleed to death slowly. You do not, however, want your partridge to bleed slowly as it flies away. I mean, to be clear, I don't want elephants to bleed to death slowly. That's horrible. But I'm assuming a poacher would want that to happen.
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