Natural selection I guess. In fact, I could think of some humans who should give birth at the top of a tall tree.
I think generally the mortality rate of ducklings is pretty high, but they’re fascinating creatures to watch imho. Lots of them nesting around a cabin we frequently visit on the Thames, and it’s all a bit of a duck soap opera. We also have a pair who basically live in our garden at home (we’re about quarter of a mile from a huge lake). In fact they’ll even waddle into the house if the garden doors are open. We frequently get other drakes fly in to try & shag the poor girly duck, much to the annoyance of her mate, who tries to peck the imposter (usually unsuccessfully) as he gets on with business. Best bit is watching them come into land in the garden, which is most entertaining. Ducks are definitely not designed to land on anything other than water.