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I just looked at a map and it doesn't always hold up. Why is Norway and Greenland so jagged, while the Kola Peninsula and the eastern cost of Russia is not?

Not to mention the erasure of some of the progress they did have between exposure to European disease, conquest, and religion.

wars, or rather threat of them, can also contribute to development, as they encourage technological progress. E.g. gunpowder lead to cannons, and that lead to better metallurgy, which had all sorts of useful peaceful uses.

Our planet saw a serious period of glaciation so many irregular features were revealed only recently. Ice isn't really very fluid so it creates irregularities, water and air are fluid and get rid of irregularities.

It is mostly a matter of time that the coast has been the coast and eroded only by interaction with nearby ocean which is the cause of irregular coastlines. the north was glaciated, and it created a new landscape (troughs, ridges, large sublinear scratch marks, and so one). It isn't just the coastlines that have obviously different features (lakes abound in recently glaciated terrains, for example). Only a few short thousands of years since the ice went away, so the rounding that happens when ocean meets land (eroding promontories like capes and points and filling in indents like coves and bays with sediment), and the work of long-shore drift, haven't had time to do the work well.

Basically, energy minimization is at work and energy is minimized by elimination of points and dents (just like a rock rolling in a stream gets rounded). The land/sea contact zone is always in the process of linearization and smoothing/rounding, equalization of forces of the ocean against the land. The presence of points acts to turn the waves toward the points and concentrate the energy of the ocean on those outstanding features, eroding them faster. The stuff broken off migrates to open spaces and fills them in.

Really, the same sort of process is happening everywhere that erosion by wind and water is occurring, leading to the smoothing of contact zones (elimination of zones of unequal exposure). Juvenile terrains and renewed terrains are marked by numerous irregular features. Those features do disappear with time. Basins fill in and high points wear away.

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When you say they euthanize your flock, who is it? A government agency?

You're right to be confused, because that passage is extremely ambiguous. It looks like the author omitted whatever Pääbo said before “Our job is to find out which of those 30,000 are most important, because they tell us what makes us uniquely human”, where he presumably clarified what "those 30,000 [things]" actually are, and I haven't found a reference to the 30,000 figure in Pääbo's major publications.

Therefore, I'll have to make my best guess about what the 30,000 and 3 million figures signify. The first refers to variations between groups (all humans and all Neanderthals), while the second refers to variation within groups (individual humans). The number of differences between two humans has a straightforward interpretation: it's simply the number of nucleotides in two people's genomes which are not the same at each location. This intra-group variation is important to keep in mind, because it complicates the matter of calculating inter-group variation: if all humans are somewhat different, and all Neanderthals are too, how can we compare them?

Generally, we calculate the genetic variation between populations (which are different species in this case) by comparing the DNA sequences that are conserved (i.e. the same) within each population. For example, we'd find all the nucleotides that are shared among most or all humans and those that are shared among most or all Neanderthals, and then we'd compare those sets to each other and see how many differences there are between them. Those differences probably contain important mutations that, so to speak, make humans humans and Neanderthals Neanderthals. To use more technical vocabulary, we would say that these differences are alleles which are fixed (i.e. shared by all members) in each population.

I assume you mean this effect: https://en.m.wikipedia.org/wiki/22%C2%B0_halo

It's due to the shape of the ice crystals. They reflect light to you at about a 22 degree angle relative to your point of view. So it's not the light reflecting back, rather it's being bent on its way to your eyes. At angles below 22 degrees, the light doesn't refract so the sky appears darker inside the ring.

Deepwater ports!? Civilisation began in the fertile crescent, where there were not a lot of glaciers, and spread largely by conquest. Ancient empires barely had seagoing vessels, let alone any use for deepwater ports, which is a very recent development.

More recently, these empires spread to the New World and Australia , while Africa remained the "Dark Continent". The reasons Arabs and Europeans failed to make headway into sub-Saharan Africa are documented in the history books. On the science side, one big breakthrough was anti-malarial drugs.

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I want an alternate history where pre-Columbian Americans domesticated bison and Moose, and there are Moose knights

It is probably comparing 2 different things, there maybe 3 million single basepair differences between you and me.

And 30.000 gene differences between us and neanderthalers, but a gene that is different, can be a single basepair that is different, or a hundrend different basepairs.

I bet if you look at single base pair differences between us and neanderthalers it will greatly outnumber the differences between you and me.

Take this next part with a grain of salt. But i do remember the genetic similarity between you and me is 99.99%, and with us and neanderthalers our dna is 99.8% similar.

I wholeheartedly disagree with this. As an anthropologist, it is undeniable determinism is a long outdated idea in anthropology and fundamentally stems from racist ideas of objective evolutionary stages of « civilisation ». Further, many large compex and imperial structures and polities existed in Africa, at all periods of its history.

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Thank you! I was coming here to ask the question that you answered about link to lack of deep water ports in Africa and Latin America.

This. It's "compare the average human genome against the average neanderthal genome".

Comparing a specific human against a specific neanderthal will probably yield 3,030,000 different genes.

Additionally, there are no animals that could easily be domesticated as draught animals in North America. This was the biggest limitation on the development of agriculture there.

I'm neither a biologist nor an anthropologist. But, it's fairly comprehensible if you consider the following three factors:

No. 1, there were way less homo running around the planet than there are today. So, in the modern human era, we had at least some time to diversify, now counting 8 billion individuals and more. Having said that, our DNA pool is still very small, which may not be a good thing if you want to calculate our chances of avoiding extinction. But it's also a testament of how specialized we are (which is also never a good thing in the long run).

The second is that we are easily tricked by the fact that only a few genes can vastly alter a creature's appearance. Think of skin color in humans or fur color in, I don't know, cats. This is evolutionary beneficial because it allows species to quickly adapt to their surroundings, even in an epi-genetic time-span. Foxes and hares are shown to completely change their fur color from brown to white when migrating to colder, icier regions within only a few generations. The same can be observed with the domestication syndrome, recently shown in foxes during a Russian study.

And thirdly, at least in Europeans, Neanderthal DNA makes up 2-3% of of their DNA already. So, part of it is "already included", if you will.

There isn't. If there's 3 million different genes between me and you, a Neanderthal can't possibly be 30 thousand away from both of us. Where did the 3 million go? So the comparison probably ignores the variance between different humans and makes a comparison off what we do have in common. And it probably also ignores the same portion in the Neanderthal genome. Which means, when comparing the portion of the genome humans share with each other with the portion Neanderthals share among themselves, there's a 30 thousand gene difference.

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A man chooses. A slave obeys.

Would you kindly?

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