Hill and Kaplan state that these two constraints have two major task; growth/maturation and reproduction. According to the book time and energy may not be used simultaneously for reproduction. I took this to mean that it takes energy to conceive and time as the birth process takes place.
The authors describe time as how much time we have left on this earth. Therefore, for most people time is impossible to measure out. I found it interesting that if an organism knew that their time on earth was low that the recommended way to manage the time left correctly is to reproduce. This view as opposed to the view of enjoy life while you can, is very unfamiliar to me. If my time on earth was limited and I knew it the last thing on my mind would be reproduction, especially if whatever is limiting my time on earth can be passed on to my off-springs.
Probability of being alive for child’s 20th birthday
|Age at Birth||Whites||Blacks||Harlem||Detroit||Chicago||Watts|
As far as race goes I am not sure what to make of that. Maybe you guys can better help me understand why it seems blacks have a lower percentage in this chart.