Isn't he pretty? Why is it that in the wild, the male is the more brightly colored of the animals to attract the female? Why is it the opposite among humans?
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Beautiful bird!
mlcwikla · 2007-09-24: 22:25
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Excellant
amiyamaiti · 2007-09-24: 23:55
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You ask a pretty big question... I'm going to have a shot at an answer, but well, here it goes! I think one way to think about it is in terms of resource allocation. Sperm is cheap to produce. We (males) produce it in bulk and the little guys don't cost us much to make. There are some costs in getting it out there (and in the right place) but maybe I'll get back to that later. Eggs on the other hand are _very_ expensive. First, they're massive compared to sperm, containing loads of protiens and structural material very crucial to an embryo's development. But even more pressing then the physical egg itself is the costs of developing that egg into a viable offspring. For creatures that live in the sea, this isn't as big of a deal. Many fish and marine invertebrates reproduce in the open water and then the development takes place outside of the parents' body, so this effect doesn't apply to them as much. Back to the land-female though, since it's so costly to raise the young, the chances a female has to do so are very limited. You might think about this in terms of how female humans can be on "monthly" cycles of fertility but on a more basic level, most animals don't live terribly long, so there may be only a few chances to reproduce. SO the long story short, females have the ability (perhaps obligation or duty) to be highly selective in who they mate with and when they mate. Males on the other hand are faced with three big issues. First, attracting a female, then inseminating the female, and finally ensuring that his offspring are carried to term by that female!! Just on the first issue there... this is where the vast majority of male/female dimorphism is thought to come from.
jameswaters · 2007-09-25: 17:47
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(part II) As my dad always put it, "Women know they got it. Men need to prove it." So if you have a population of male birds, and one of them can stand out from the others in a way that is suiting to the female, perhaps he is more red-colored for example, then if he successfully reproduces and the others don't... the next generation of male birds in the population will have a higher probability of being bright-red colored. The same thing works for things like beetle horns and elephant tusks and the feathers on your phantastic pheasant! Now, I think i've gone on for way too long, but let me just say, I've hardly begun to cover the topic. Think about the two other main problems males face (i mentioned earlier). One of them leads to some real interesting complexity in the zoological diversity of sexual reproduction... and the other ... well that gets into the evolution of cooperation and social behavior! I'll just mention something about that last one real quick. It seems... that even though women "can" be super-selective about who they choose to mate with... a lot more then we thought, it turns out females do the opposite in nature -- that is, mate with lots and lots of males! Why? If they can do this successfully, then that means there are lots of little spermies inside her competing to fertilize an egg. The "best" one will win... faster, stronger, etc. So its actually to her advantage to do this! But, it's _not_ to the average male's advantage! So what do men do? Wellll... some have evolved incredibly bizarre methods of "cleaning out" the female of the species before mating with her, others dedicate their lives to staying with and protecting the female.... me, i'm going to try and see if I can just take good pictures and win her heart that way. : - )
jameswaters · 2007-09-25: 17:47
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I love the picture and the title!
jwideman · 2007-09-25: 20:44
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