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No. A brain's processing power isn't connected to brain size. When you have big brains, it usually represents storage space for memories.

A crow is a good example. Highly intelligent with an IQ equal to a human 7 year old. Dogs and cats have bigger brains but the IQ of a human 3 year old.

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It's very rare but possible. The majority of peripheral dopamine comes from peripheral sympathetic nerves which in part use dopamine to communicate. Some of this dopamine is taken up in the blood stream. Interestingly, there's almost as much dopamine in your blood as adrenaline though what it's doing there is not really known.

https://academic.oup.com/endo/article/151/12/5570/2456083?login=true

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3373991/

I would definitely not use Economic Explained as an intro to economics, EE in reality is on the lower end of quality for pop-economics related content.

A better alternative is something like Marginal Revolution University which create videos on Economic theory, applications, etc. These videos are created by actual professional economists who are active in publishing. Plus, it delves in to the actual theory itself, which EE doesn't really do.
I especially recommend MRU's Mastering Econometrics series which feature Joshua Angrist (Nobel Prize Winning Economist) explaining Econometrics (a challenging field) in a fun and comprehensive way that most can just pick up and understand.

Alternatively, picking up an introductory Microeconomics or Macroeconomics textbook is reliable too, even if less engaging.

Some do secrete dopamine. Dopamine is a metabolic precursor to epi and norepi. There are small amounts that get secreted, and certain rare subtypes of pheo will secrete dopamine. However, like everyone else said, dopamine isn’t able to cross the BBB so it’s not useful for treating PD.

Some perspective you might need here:

1- It's not feasible to screen all the virus present in a bat population. If you tried you'd likely find many new virus no one ever described and still only know a small subset of the viral population within the bat population.

2- Vírus won't stay still and remain the same. The sars-cov-2 we have today is different from the one we first described and that would also apply to it's ancestors. Even if we find this ancestor it wouldn't be a 100% match. Parasites adapt to their hosts and sars-cov-2 jumped the species barrier at least once and maybe twice. The simple fact that a virus is in different hosts put new selective pressures on them.

3- We have find similar virus in the wild. The RaTG13 has around 96% identity to sars-cov-2 genome. This is not enough to say that one came from the other but shows that we can find some similar things if we look closely to betacoronavirus populations in bats.

Neurons are tiny. The capacity for intelligence seems to be linked much more with how they are connected than how large the resulting structure is.

We would only expect to see intelligence evolve in an organism to the degree that it improves their fitness. Intelligence is not a universally good trait; it is expensive to maintain.

Koalas are drop dead stupid because they’ve gotten themselves stuck in a valley on the fitness surface, not benefitting from intelligence. Ants don’t need to be individual geniuses, because the colony’s intelligence is an emergent property arising from many much less complicated little nodes.

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Makes more sense, thanks

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Bat origin is an unproven theory. One possibility is that the virus originated in bats and was passed to another animal where it evolved to become SARS-CoV-2.

Bats have really interesting immune systems which are really good at combating viruses. For this reason they may make a good candidate for viruses to evolve and jump to another species.

And since bats are so good at fighting off viruses the original virus would no longer exist.

Technical sidenote: keep in mind that COVID-19 is the disease associated with the virus which is called severe acute respiratory syndrome coronavirus-2 or SARS-Cov-2.

Edit: added "severe acute respiratory syndrome"

We add an extra medicine to block an enzyme that would convert the medication we want to be converted in the brain too early, out in the peripheries.

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Lol, I just commented the exact same. Black holes, james web telescope, how stuff behaves at close to lightspeed, no problem. But no idea what these people are talking about

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That is not how time dilation works. It is not a 1 to 1 rate or people who are twice as heavy would experience them moving at super speed. At the surface of the Sun, time dilation is at a rate of ~67 seconds per year. Or, for every year on Earth only 364 days, 23 hours, 58 minutes, and 53 seconds will have passed.

As for how the star runs out, the end result of fusion is that two hydrogen atoms turn into 1 helium atom. Eventually, all the hydrogen atoms in the star have been fused. Of course there will be some hydrogen left in the star, but it is too diffuse to continue fusing at a rate to sustain the star. Remember that stars are a delicate balance between the pressure exerted by all the heat and fusion, and the gravity trying to contract it.

Last, the sun is 1.3 million times the size of Earth by volume and 333,000 times the mass of Earth.

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The overall energy density of light today is about one ten thousandth (10^(-4)) that of matter or dark energy. Thus, its contribution to the overall spacetime curvature is negligible.

That was not always the case, though. Despite all of the light emitted in galaxies, the cosmic microwave background (CMB) still dominates the energy density in radiation (see for example the first figure in this article). This is not light that was "emitted" per se; rather it is left over from a time when the universe was much hotter and denser. Between a few minutes and roughly 50000 years, this light dominated the energy density of the universe. (In particular, the energy density was about 60% photons and 40% neutrinos.)

The gravitational influence of this radiation (that is, its influence on spacetime curvature) led to a different cosmic expansion history. When radiation dominates, cosmic expansion decelerates more efficiently than when matter dominates (the size scales as time^(1/2) rather than time^(2/3)).

Another major impact of radiation domination is that structure growth is suppressed. Matter can cluster, so for example, any small density excess tends to pull in surrounding matter, becoming even denser. That's what is meant by the growth of structure. However, radiation cannot cluster, so when radiation dominates, structures grow much less efficiently.

Thanks. I'll check that out

Good points! I really just mean the analogy to be about how people can do extraordinary things when they are trained over time to do them. Surgery very difficult to get into, training excruciating and those factors help weed out most. The few left in the subspecialty surgery groups really love it, really deserve to do what they do and are of a different breed. Even among doctors, who are all pretty good at working hard and focusing.

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