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>For what it's worth, the point where unique ancestors would outnumber the population is precisely 30 generations.

I don't think it's necessarily safe to use this as a lower bound for the posed question in terms of how far back we'll be going. Obviously the max number of unique ancestors alive at the same time must be lower than 2^30 (*Edit, maybe not technically, but probably in practice on Earth today - see my edit below), but it does not follow from that that the widest generation must be less that 30 generations ago. What happens instead is that very quickly as you go back generations, the number of additional ancestors in the next generation back starts to grow very slowly, and then in fits and starts as you have individual ancestors who migrated a significant distance.

The more determinative fact will be the distribution of the size the population over time - both the global ones, and the sizes of the populations to which you are likely to be genetically linked. Populations that have grown significantly in the somewhat recent past (but not too recently) will have the max number of ancestors being very recent, because you can hit a number of ancestors alive at the same time that outnumber the people that actually lived in early generations in that population.

But for sparsely interconnected populations that have had stable sizes for centuries/millennia, you could expect to very slowly attain small numbers of new ancestors each generation for well over 30 generations, if the growth rate is low enough.

Edit: Come to think of it, perhaps more important is that the number of unique ancestors in generation X back from yourself can actually outnumber the people who were alive at the same time as any given one of those ancestors. Go back far enough and you'll have ancestors from different parts of your family tree in the same ancestral generation who lived centuries apart. The further back you go, the more pronounced this effect becomes.

As far as I know: no, unfortunately not. There are a few things against the symptoms (medication and deep brain stimulation).

But the mechanism responsible for PD is still more or less unknown , so basic research is still being done. That's why (again: afaik) there is nothing revolutionary in sight at the moment.

(I wrote my MD loosly on the subject, so I have some insight)

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I used Dodelson's Modern Cosmology originally. However:

• There's a recent, very concise review article on the growth of structure.
• For the expansion history, the Wikipedia article on Friedmann equations has most of the relevant mathematics.
• The thermal history is more complicated. I hinted at some of its features when I mentioned 40% neutrinos and that photon domination only begins at a time of a few minutes (that's about when the electron-positron phase transition ends). I frequently refer to this article for details about the thermal history.

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People tend to focus way too much on neurotransmitters, rather than neural pathways. It’s like trying to understand a military conflict while only learning about the bullets being used.

If we consider the hive an organism, we could consider each ant a neuron, and thus the high intelligence of the hive.

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Complex emotion is impossible without a high level of intelligence because the "complex" part is dependent on self awareness or even more abstract thinking (object permanence, cause effect, etc)

So splitting hairs about complex emotion is redundant. Any emotional complexity is dependent to a high degree on intelligence, bringing the discussion back to neuroconnectivity

It's correlated, but it's not a function (intelligence vs size)

Obviously more connections is possible with more cells but as was said earlier in the thread, crows are much much more intelligent than a massive creature like OPs mom

Are the therapies in the works going to prevent PD, stop its advancement, or outright reverse it?

And any insight on how far away from FDA approval they are?

My father has had it for almost 20 years now so I’m trying to keep up with this stuff but it’s pretty far outside my usual field.

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It's very tricky to find a natural reservoir of a coronavirus like this. You might want to compare with SARS 1, where a very similar virus was found in palm civets being sold for food at the time of the outbreak. But that was a combination of luck and extensive testing. The civets are likely to have been an intermediate step, hosting the virus after it left bats and before it entered humans. But remember, viruses are constantly mutating, so the virus in the civets wouldn't necessarily be the same as the virus in the bats or the people.

Anyway, why can't we do this with SARS 2? Because when the outbreak happened, China locked down their wet markets and killed most of the animals, which means there was very little sampling done. This probably means we'll never know exactly what path the virus took to get from bats to people.

Several studies over the past two years have found deer to be a covid reservoir

https://scholar.google.com/scholar?q=covid+deer+reservoir

There are plain english explainers on the NPR website but not sure if non-study links are allowed in this sub

There may be, tentatively, such a correlation in mammals, but as you say, certain birds are already very much a counterexample.

Their ancestry would spread to Alaska present day Alaska on only a few hundred years. Paleo Eskimo, who lives from Russia through Alaska into Greenland. They acted as the bridge between the old and new worlds 4,500 and 1,500 years ago.

The world has been much more interconnected than what most would believe. It takes only one person after complete mixing to spread an entire continent of ancestry. Do not underestimate just how much mixing occurs in 1,000 years, that is enough time to completely mix all of Europe.

Brains of birds are also wired super differently. When it comes down to it's about the number of neurons and connections that make you smart. For very small animals, size can be a limiting factor for getting super smart, but the size of cells is also different between small and big animals. So, bigger brain doesn't necessarily mean more cells and computing power

Also, carbidopa works in this role because carbidopa itself cannot cross the blood-brain barrier. That's why it blocks peripheral absorption of levodopa but won't interfere with levodopa absorption in the brain.

The distance is really hard for me to really understand. Currently the fastest manned vehicle we have has been capable of about 17,000 mph. At that speed it would take right around a 855600 years to reach 667CC. I'm sure we'll wait for better technology before attempting that kind of trip.

Non-carbon based lifeforms - definitely hypothetically possible. Unfortunately we don't currently have evidence of lifeforms using anything but carbon biochemistry. My personal belief is it is absolutely possible. Silicon has quite a few similarities to carbon and that's just an example of life having an analogous biochemistry. Who knows what's possible with the diversity that could be experienced in different environments?

In the cosmological context the current contribution of photons to the energy density of free space is negligible.

However there are entirely theoretical phenomena that occur under extreme radiation-dominated energy densities. Most notable is the Kugelblitz: a black hole formed by concentrating light (or heat) sufficiently dense as to curve spacetime and create an event horizon. This entirely theoretical black hole is one of a class of phenomena proposed by Wheeler in 1955 called "Geons" in his paper of the same title.

A model of these (again theoretical) geons has been extended to a candidate for dark matter called Graviballs. Which is a neat idea, but has no supporting observational evidence that I'm aware of.

Maybe dolphins. There's a video I watched in a linguistics class that was investigating dolphin communication using dolphins that were trained to perform in dolphin shows with various hand signals from their trainers. They had a hand signal for "together" that typically was used to have the dolphins coordinate jumping out of the water or something similar at the same time. So the trainers would use hand signals to say "do a flip together" and the two dolphins would time it so they were flipping at the same time. Pretty cool but not anything crazy. They had another hand signal that basically told the dolphin to "make up a trick", when they used this hand signal typically the dolphin would do some kind of flip or jump or whatever they felt like doing. In this video they had 2 dolphins, and they combined hand signals to tell them "make up a trick together". You can see in the video the two dolphins swim down to the bottom of the pool, squeak at each other a bit, and then come up and do the exact same thing at the exact same time.

I think communication becomes language when you can use it to express new ideas, and this is the only example I've seen of that obviously displayed in animals. I'll see if I can find the video, it is really cool.