ralfy wrote:Ibon wrote:
Read about it here Ralphy
https://en.wikipedia.org/wiki/Secondary ... acteristic
They are believed to be the product of sexual selection for traits which display fitness, giving an individual an advantage over its rivals in courtship and aggressive interactions. They are distinguished from the primary sex characteristics, the sex organs, which are directly necessary for sexual reproduction to occur.
Secondary sex characteristics include manes of male lions and long feathers of male peacock, the tusks of male narwhals, enlarged proboscises in male elephant seals and proboscis monkeys, the bright facial and rump coloration of male mandrills, and horns in many goats and antelopes, and these are believed to be produced by a positive feedback loop known as the Fisherian runaway produced by the secondary characteristic in one sex and the desire for that characteristic in the other sex. Male birds and fish of many species have brighter coloration or other external ornaments. Differences in size between sexes are also considered secondary sexual characteristics.
I don't think males from these species buy or put on feathers, tusks, etc., in a way that male humans would wear expensive sunglasses. I'm not even sure how phenotypes can now be equated with virtual value of marketed products.
Try reading up on Bower Birds (I think that's right.). There is a wonderful description of them and how their behavior directly answers your question in "That Thing with Feathers."
But also that book I can't recall that goes into the way conspicious consumption displays work in humans.
My internet is extremely poor so I can't find and post links.