Continuing the discussion from A Concordist Rossian View:
How exactly did mandarin ducks evolve to be this way? When did they arise? Was it artificial selection? Sexual selection? Or what?
https://www.nytimes.com/2018/12/03/nyregion/hot-duck-mandarin-central-park.html
Iâm wondering what the âselective pressuresâ were on all the evolutionary precursors that produced such a wonderful creature. (Or is âcreatureâ not politically correct within biologistsâ circles since its etymology involves âcreationâ? 
)
I donât think the question has been studied for this species, but itâs most likely sexual selection. Wood ducks, their congeners, are almost as showy, and lots of species in the family Anatidae have fancy feathers and colors, as well as courting behaviors in which they prominently display their ornaments. To suppose that itâs all for your benefit is anthropocentrism at its worst, a pernicious feature of some brands of Christianity.
No. These are wild animals. Only two species of ducks have ever been domesticated.
Interestingly (or perhaps not), the next closest relative of the mandarin, the Muscovy duck, is one of the two domesticated ducks, and there sexual selection has gone a different route. Itâs the duck with the greatest sexual size dimorphism of all anatid species, with males weighing around twice the weight of females. The males also have fancy red, knobby facial skin.
I love wood ducks â we have them around here and swimming in the creek that borders our place. Apparently the moms share babysitting duties, because when I regularly rode the beautful bike trail that borders the canal in our town, I have observed the numbers in the broods.
I havenât seen it up close, but itâs humorous to picture webbed feet wrapping around tree branches.
What does that sentence mean?
Several things, but I presume what youâre having difficulty with the babysitting part?
It means, for instance (itâs been several years, so I donât remember the exact numbers), that on repeated occasions I will have observed two broods of six with their moms swimming in the same area, but on another occasion in the same area I will have seen one mom with a dozen chicks and the second adult female not to be seen.
No, I have difficulty mostly with âI have observed the numbers in the broodsâ and how it connects to anything. But now you have explained what you meant. May I suggest you devote more effort to saying what you mean the first time?
Many duck species do whatâs variously called âcrechingâ or âbrood amalgamationâ. Since ducks donât feed their ducklings, thereâs no cost to the mother, and there may be some benefit from increasing the number of targets for a predator, thus diluting the risk to individual ducklings.
Since you already knew all that, Iâm surprised at your inability to infer.
The problem is that I donât know what you know.
Yes, you do have a problem. 
