Being a man has always been dangerous. There are about 105 males born for every 100 females, but this ratiodrops to near balance at the age of maturity, and among 70-year-olds there are twice as many women as men. But thegreat universal of male mortality is being changed. Now, boy babies survive almost as well as girls do. This meansthat, for the first time, there will be an excess of boys in those crucial years when they are searching for a mate. Moreimportant, another chance for natural selection has been removed. Fifty years ago, the chance of a baby （particularly aboy baby） surviving depended on its weight. A kilogram too light or too heavy meant almost certain death. Today it makesalmost no difference. Since much of the variation is due to genes, one more agent of evolution has gone.
There is another way to commit evolutionary suicide: stay alive, but have fewer children. Few people are asfertile as in the past. Except in some religious communities, very few women have 15 children. Nowadays the num-ber of births, like the age of death, has become average. Most of us have roughly the same number ofoffspring. Again, differences between people and the opportunity for natural selection to take advantage of it havediminished. India shows what is happening. The country offers wealth for a few in the great cities and poverty for theremaining tribal peoples. The grand mediocrity of today——everyone being the same in survival and number of off-spring——means that natural selection has lost 80% of its power in upper-middle-class India compared to the tribes.
For us, this means that evolution is over; the biological Utopia has arrived. Strangely, it has involved littlephysical change. No other species fills so many places in nature. But in the past 100, 000 years——even the past 100years——our lives have been transformed but our bodies have not. We did not evolve, because machines and societydid it for us. Darwin had a phrase to describe those ignorant of evolution : they "look at an organic being as a sav-age looks at a ship, as at something wholly beyond his comprehension. " No doubt we will remember a 20th centuryway of life beyond comprehension for its ugliness. But however amazed our descendants may be at how far from Uto-pia we were, they will look just like us.
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