[alancalverd (OP)]

Birds lay between one and a dozen eggs, once or twice a year, and incubate them until they hatch.

Except domestic chickens, which lay one egg every day and mostly walk away from it. Clearly not a great survival strategy for a ground-nesting forest dweller. How and when did they get from there to here?

[vhfpmr]

Selective breeding?
What happens to domestic chickens if they're set free in the wild, can they still survive?

[Bored chemist]

domestic chickens

Are not

a ground-nesting forest dweller.

It turns out that "being helpful to humans" is a remarkably good survival trait.
Ask potatoes and cattle.
It's also why dogs can be found in just about every bit of the world.

[alancalverd (OP)]

Selective breeding tends to enhance or remove an anatomical characteristic, and in the case of dogs, to slightly displace the collaborative family behavior so that humans become the alphas - though given the opportunity, feral dogs soon organise themselves into packs. Canine behavior clearly has a strong element of nurture and intellect overlaying nature. Cattle are just fatter versions of their wild ancestors: lactation still stops a few months after parturition and the cow becomes fertile again. But the fundamental reproductive cycle of the chicken is very different from any wild bird and runs on a continuous quasi-24 hour rather than an annual cycle.That's pretty amazing.       

[alancalverd (OP)]

Selective breeding?
What happens to domestic chickens if they're set free in the wild, can they still survive?

In a flock, and particularly with a few males around, they can ward off small predators and breed successfully, but the daily egg seems a bit extravagant - most hens only get broody and incubate their eggs once or twice in their lifetime.

[Bored chemist]

It's not unusual for a bird to lay  several eggs over the course of several days.
https://en.wikipedia.org/wiki/Clutch_(eggs)#/media/File:Starling_eggs.jpeg

And it's not rare for then to do it again if the eggs are taken by a predator.
https://en.wikipedia.org/wiki/Clutch_(eggs)

So, while the domestic hen (and human intervention) take this to an extreme, it's not as if the behaviour isn't present already.

[evan_au]

What happens to domestic chickens if they're set free in the wild, can they still survive?

On a visit to Kauai (one of the Hawaiian Islands), we saw many wild chickens.
- The guide said that a hurricane had gone through a chicken farm, and the birds just went native, and flourished...
- But maybe the story goes back further than that...

See: https://www.nytimes.com/2015/04/07/science/in-hawaii-chickens-gone-wild.html

[vhfpmr]

Selective breeding?
What happens to domestic chickens if they're set free in the wild, can they still survive?

In a flock, and particularly with a few males around, they can ward off small predators and breed successfully, but the daily egg seems a bit extravagant - most hens only get broody and incubate their eggs once or twice in their lifetime.

That seems to suggest an element of "choice" in how often they lay.

[vhfpmr]

a hurricane had gone through a chicken farm, and the birds just went native

Now I come to think of it, I've driven past here:
https://en.wikipedia.org/wiki/Chicken_roundabout

[Bored chemist]

Selective breeding?
What happens to domestic chickens if they're set free in the wild, can they still survive?

In a flock, and particularly with a few males around, they can ward off small predators and breed successfully, but the daily egg seems a bit extravagant - most hens only get broody and incubate their eggs once or twice in their lifetime.

That seems to suggest an element of "choice" in how often they lay.

I strongly suspect that the mode of that distribution is zero; most don't live long enough to breed.

[Just thinking]

Birds lay between one and a dozen eggs, once or twice a year, and incubate them until they hatch.

Except domestic chickens, which lay one egg every day and mostly walk away from it. Clearly not a great survival strategy for a ground-nesting forest dweller. How and when did they get from there to here?

I think that domestic chickens have learned to lay more eggs in exchange for feed and protection If they don't supply eggs they will supply their lives. This is learnt by the chicken and enhanced by selective breeding. All bade layers go in the pot.

[Petrochemicals]

I don't think they just walk off from their chicks, from everything I remember about primary school I'm pretty sure that the mommy chicken in the farmyard had a string of baby chickens with her, I also remember birds have to sit on eggs to get them to hatch or something.

On the subject of selective breeding what sort of sheep would survive if it's fleece never fell out and continually grew, or what sort of cow would have mammaries so gargantuan that walking was near impossible.