Hard to come by in normal language acquisition, though. So it probably doesn't quite work like that.

Actual position (rot13):

V'z n irtrgnevna (ab zrng be svfu; V qb rng rttf naq qnvel) naq unir orra sbe nobhg 8 lrnef, fvapr zl zvq/yngr grraf. Zl trareny cbfvgvba ba qvrgnel pubvprf vf gung vg'f n fhssvpvragyl crefbany vffhr gung vg'f orfg abg gb vagresrer jvgu bgure crbcyr'f vqrnf ba gur znggre. V qb oryvrir vg'f rguvpnyyl onq gb rng zrng sbe n inevrgl bs ernfbaf, ohg znal rguvpnyyl onq guvatf ner bhgjrvturq ol bgure pbafvqrengvbaf, naq guvf znl nccyl sbe znal bzaviberf. Fvapr V arire qrevirq gung zhpu cyrnfher sebz zrng va gur svefg cynpr naq V'z va gur unccl cbfvgvba gung V'z noyr gb rng n gnfgl naq urnygul irtrgnevna qvrg, nal tbbq guvatf nobhg zrng pbafhzcgvba qba'g bhgjrvtu gur rguvpny ceboyrzf sbe zr. V fhfcrpg vg jbhyq or rguvpnyyl tbbq sbe zr gb tvir hc qnvel naq cbffvoyl rttf, gbb (be ng yrnfg or zber pbafpvragvbhf nobhg jurer V trg gurz sebz), ohg V cebonoyl jba'g qb gung nal gvzr fbba.

Omnivores:

1. I don't live in America so I don't have direct experience here but my vague impression is that many Americans eat a lot more meat than they need in their diet and I'm pretty sure high levels of meat consumption are correlated with the usual-suspect nasties like heart disease, stroke, etc. I don't know enough about the research to be sure whether this is causative, or has more to do with the fact that a high-meat diet is correlated with other factors that do make for an unhealthy diet, eg lack of vegetables. As for the planet, I think if everyone ate as much meat as the average westerner, we might have a problem, so the current methods probably aren't sustainable. However, it's likely that with advancing technologies and social changes we will be able to keep supplying meat by some means in order to meet demand. If that included a reduction in demand that wouldn't be a bad thing.

2. Factory farming does seem morally problematic and I believe it would be morally preferable to farm less efficiently. I am not averse to spending more money where I can afford it to avoid the worst of factory farming (I only buy free-range eggs, for example). However, I appreciate that for some people this is the only way they can afford meat and animal products.

3. I wouldn't want to absolutely ban the hunting/farming/eating of any animals, but for cultural reasons there are several animals I couldn't stomach the idea of hunting/farming/eating myself, eg dogs.

4. If all my friends were vegetarians I would probably end up eating significantly less meat as I would avoid it when cooking for or with them. However, I'd likely still eat my usual diet when left to my own devices or when in a restaurant with meat options. If vegetarianism became culturally pervasive enough that I would, eg, have to go to a special shop in order to buy meat, that might become a different matter.

Vegetarians:

1. I'm a bit conflicted on this one, torn between curious to try lab-meat and a bit intuitively grossed out. It's been so long since I've eaten meat of any kind that I'm just not sure it would appeal at all. Beyond being willing to try it as a one-off, I would need to learn more before being ok with incorporating it into my general diet. I wouldn't have an ethical problem with it in terms of animal welfare, but I'd want to know about the environmental costs compared to food I currently eat. I would be most likely to have an interest in fish-meat produced like this, because I suspect that occasional fish would be the single healthiest addition to my diet as it is currently.

2. I don't disagree strongly. It's fairly obvious that humans are biologically omnivores and meat in reasonable quantities (whatever that means) doesn't harm us. I also find it to be fairly obvious that a meat-free diet doesn't necessarily harm us either. There are plenty of completely healthy vegetarians, including high-performing athletes.

3. For the most part I don't think other people's diets have much to do with me. I have never tried to get someone else to become a vegetarian or vegan. I accept that many other people get a lot more pleasure from meat than I ever did, or have different health needs, financial situations, cultural contexts, cooking abilities, etc etc that make the trade-offs quite different to how they line up for me. The furthest I go in the direction of interfering with other people's diets is not cooking meat for guests even if they are omnivores (I generally find that omnivores are quite happy and excited to try interesting veggie dishes, anyway). If asked, I'll also happily share how much I like being a vegetarian, tasty recipes, and surprising information about how I don't actually find it difficult to get enough protein.

4. The primary health risk of eating meat in moderate amounts is probably food poisoning, at a guess! As a vegetarian I'm probably a lot less likely to eat something bad or undercooked and get ill (never have, in fact). Eating meat in excessive amounts is probably correlated with all the usual-suspect nasties like heart disease, stroke, etc, but I don't know enough about the research to know whether that's causative or has more to do with a correlation (at least in developed countries) between lots of meat and poor diet in other ways (eg not enough vegetables).

For free stuff, we just have a place in the staircase where people drop things that are still good but not needed by their previous owner (mostly books). This works with zero explicit coordination.

I'm kind of amazed/impressed that this works, based on my experience of communal spaces. Don't people ever leave junk that they can't be bothered to get rid of? Does anyone adopt responsibility for getting rid of items that have been there a long time and clearly no one wants?

Since most women managed to reproduce, we can assume a winner strategy is having a large number of daughters

But if everyone adopts this strategy, in a few generations women will by far outnumber men, and suddenly having sons is a brilliant strategy instead. You have to think about what strategies are stable in the population of strategies - as you begin to point towards with the comments about game theory. Yes, game theory has of course been used to look at this type of stuff. (I'm certainly not an expert so I won't get into details on how.)

If you haven't read The Selfish Gene by Richard Dawkins, it's a fun read and great for getting into this subject matter. How The Mind Works by Steven Pinker is also a nice readable/popular intro to evolutionary psychology and covers some of the topics you're thinking about here.

Sure, there are conversations where it doesn't matter and can actually make for a good exchange.

I like writing as a communication medium too. I'm a slow thinker, and I'm even slower when a person is looking at me and waiting for me to finish the thought (or the conversation is simply moving on without my thought), so the non-real-time nature of written communication helps.

Granted, we would not edit things like hair or eye color because it would feel like an unwelcome intrusion into other person's individuality even when the person does not exist yet. But we would edit out the potential problems.

One problem with this perspective is that not everyone is agreed on what is a "potential problem" and what falls into "[an]other person's individuality". Deafness springs to mind as an example, and in the other direction, what if ginger hair would increase the odds that your child got bullied?

Interesting. I get grapefruit (which I like better than strawberries) to be quite sour, but not bitter at all.

I definitely understand this perspective, although I think I have it the other way round to you in terms of what the default is (as well as to a lesser extent). That is, I pretty much like the taste of most foods, but a texture that I can't tolerate can easily put me off a food anyway. And if I find something actually disgusting, as opposed to just not what I prefer, it's nearly always a texture issue.

Sure, here's my preferences:

spicy foods I enjoy moderate spice. Really really spicy is a bit much for me, and I do tend to drink a lot of water when eating spicy foods, but I like them.

sweet things Definitely have a bit of a sweet tooth: I enjoy these and would generally prefer to have a dessert over a starter in a 2-course meal, for example. I like chocolate but I'm not sure that's a particularly great example for this category, as I also enjoy it in its less sweet forms: very dark chocolate, unsweetened drinking chocolate. It is also definitely possible for things to be too sweet for me to want them in large quantities.

alcohol Don't like, don't consume to any significant extent.

drinks I drink a lot of water and no-added-sugar orange squash (I think this is quite a British thing: it's similar to a cordial but somehow different. Comes in concentrated form and you add water to make the drink up). Juice (usually orange) sometimes; milk occasionally. I like lemonade but tend to reserve it for pubs or eating out, neither of which I do all that frequently. Don't like ice in my lemonade!

hot drinks Until a few months ago, I drank a fair bit of tea but decided the caffeine was bothering me, so now I drink tea (with milk but no sugar) a couple of times a week and most days have either rooibos or some herbal tea like peppermint or chamomile. Hot chocolate or chocolate Ovaltine quite often. Coffee extremely occasionally (like once or twice a year maybe).

bitter foods Mostly like. I really enjoy olives and vegetables that some people describe as bitter like broccoli or sprouts.

excluded vegetables Can't think of any really... I used to be not that fond of parsnips but seem to have got over that. Fruit and vegetable preferences for me are a lot more about texture than taste, so sometimes a vegetable that I really like when I cook it can be a bit off-putting to me when cooked in a form I'm not keen on. I'll probably still eat it though. Oh, water chestnuts, I don't like those. (Are they a vegetable?)

animal based products Haven't eaten meat for years so can't comment on preferences. I like and consume quite a lot of dairy and eggs in various forms, including goats' and sheep's cheese which no one else in my family can stand on account of the baffling complaint that "it smells like a goat/sheep".

tofu or other replacement-animal-products I probably eat less of these than many vegetarians, although I have no objection to any of them that I've tried. I just prefer vegetables and legumes and so on, I guess. Tofu is the most often used in my cooking (maybe once a week or slightly less).

sour I quite like citrus flavours, but in relatively small doses I suppose. Sour fruits are fine modulo texture. I like grapefruit, for example. It takes me quite a long time to consume this type of thing if it's in concentrated form, as I find it to be a very strong taste (a small glass of orange or grapefruit juice can last me ages, for instance).

vinegar No objection, don't use it that much.

starchy foods I like bread a lot, fresh from the bakery (or our own oven) being the best kind pretty much regardless of what sort of bread it is. Also eat pasta, rice and potato very regularly. Not much preference between these really, although I find I eat less if I'm eating potato: it seems more intense and filling.

salty foods I think I have quite a low tolerance for salt. I don't add it to many things when cooking and often find processed (or even just not-made-by-me) soups etc to be overwhelmingly salty. I seldom add it at the table, steamed cabbage being an exception that I feel benefits from a bit of salt.