Cash Cows

Think in scale. If you don't breed your cows, the neighbor's bull will come over the fence and do it for you, so you're incentivized to keep your cows bred. One bull will handle a large number of cows, so picking desirable bulls and a variety of interesting cows gives (roughly) $nCows potential picks for the next generation per herd (and Bakewell had many). Cows gestate for 8 months and results are frequently apparent in very young calves. Sexual maturity hits at 12-15 months (though, traditionally, first calf heifers were bred closer to 2 years), so 4 generations per decade in direct lineage isn't impossible.

It's not particularly difficult to select for specific traits when you consider inbreeding (which Bakewell did) and linebreeding (same idea, but avoiding excessive coefficient of inbreeding). Arguably, changing the muscle distribution on a domestic cow given a plethora of similar domestic breeds with different muscle distribution is easier than shrinking the adrenal gland in a wild fox given only wild stock.

Not to diminish in any way Bakewell's accomplishments. He revolutionized the field of animal husbandry.

Late edit to add an example: our (big, light brown, horned) Jersey milk cow came into heat and the (smaller, oreo-colored: almost black, white band around the belly, almost black; no horns) Belted Galloway bull jumped the fence, siring a heifer with small horns, a redder black, a splotchy band, and significantly greater size. Her offspring (against a bull from the same herd, possibly her sire) are medium-dark brown with a red tinge and a splotch of white, have no horns, and are still larger. Their offspring are very dark, solid brown with obvious red in sunlight, are still larger than the non-Jersey lines, and have, in every example, excellent conformation. All this in the last 7 years. The most recent generation will calf next year. Imagine what we could do with a targeted selection program!

> Bakewell ended up doing similar for his sheep, “so plump that we have measured several of them and found them broader than they are tall … having on each side a great lump of fat which the farmer called cloven flank”.

Downside: they can get stuck on their backs and die https://www.youtube.com/watch?v=guEyxTpevFo

A thing can be bad for two reasons; to recognize that it's bad because of one of them is not to deny that it's bad for the other.

I am surprised more people are not doing this and its variants. It only takes someone, or ideally a family, willing to start a project that spans multiple decades - something people do all the time with careers and other hobbies.

To me it seems strange how concentrated these efforts are in some communities while seemingly silent in others. Cannabis farmers and pepper farmers nerd out about it a lot. I think dog breeders do although I suspect the existence of “institutions” like AKC and dog shows channels their efforts into ossification of existing breeds. I’m sure plenty of regular livestock breeders are trying but you don’t hear about it and they don’t seem to have done anything truly crazy in a while (that I’m aware of) to the extent Pepper/Cannabis breeders have.

Just to demonstrate what’s possible: Belyayev was able to make huge progress domesticating foxes in just 26 years [0]. Dachshunds [1] didn’t look anything like their current forms until the late 19th century (I think a lot of dog breeds saw huge changes around this time but not certain). Cannabis breeding didn’t even really start until the 1960s and we have an absolutely massive assortment of strains, not just differing in subjective “flavor” and “effects” but with quantifiable massive differences in concentration, overall volume of flower produced, and flowering behavior. Because people didn’t understand what it was, some say that the domestication of yeast [2] didn’t even start until the 16th century.

All that said it baffles me why more people aren’t trying to domesticate bears, otters, lemurs, raccoons, etc. Maybe not bears, but the rest could probably be domesticated in a human lifespan and (not bears) without many expenses year-on-year. I’ve always said I’d try this if I came into the means to do so at a young enough age. Even for medium-scale farmers of your regular-old cow, having some kind of special breed or phenotype seems like a great way to move up-market with a differentiated, unique product.

[0] https://en.m.wikipedia.org/wiki/Dmitry_Belyayev_(zoologist)

[1] https://en.m.wikipedia.org/wiki/Dachshund

[2] https://www.sciencedaily.com/releases/2016/09/160908130552.h...

I would think of it as annealing/gradient descent instead of some kind of Markov process where maybe you get lucky every 2-5 years. You are not breeding for the purpose of getting one animal with the trait (well you can, but not necessarily) so much as you are trying to influence a population of animals to display the traits you want over time. Maybe first generation you have an average yield of X across 100animals. And you don’t let the lowest yielding 50% breed (or just have them breed less so you can’t counteract inbreeding), now generation 2 has an average yield of 1.05X across 100animals. If you know the trait is heritable it seems pretty straightforward.

What’s challenging is I guess you can’t know a priori much about the actual genetics at play so at a certain point it becomes hard to know what’s simply phenotypic variance independent of genetics and what’s actually genes - it could take quite a while to be certain you’ve “converged”. Or for something more subjective/without an obvious strong genetic link, it could take a while to rule out the possibility of breeding for the trait at all.

Like for humans, I’m highly confident you could do some basic process over 10 generations to breed some ridiculously tall people. But it helps we know it has huge variance, is highly heritable, is easy to measure, and is polygenic. Probably a lot harder to try to breed “nice” people or people with thick skin. The fact dog breeders can do things like that is much more impressive IMO.