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1 " a typical chromosomal DNA molecule in a human being is composed of about five billion pairs of nucleotides… But since there are four different kinds of nucleotides, the number of bits of information in DNA is four times the number of nucleotide pairs. Thus if a single chromosome has five billion (5 X 10^9) nucleotides, it contains twenty billion (2 X 10^10) bits of information… We also see that if more than some tens of billions (several times 10^10) of bits of information are necessary for human survival, extragenetic systems will have to provide them: the rate of development of genetic systems is so slow that no source of such additional biological information can be sought in the DNA. "
― Carl Sagan , Dragons of Eden: Speculations on the Evolution of Human Intelligence
2 " If you look at all the variables in nature that are saidto determine human “sex,” you can’t possibly find one that will unequivocally split the species into two. Each of the so-called criteria of sexedness is itself a continuum—including chromosomal variables, genital and gonadal variations,reproductive capacities, endocrinological proportions, and any other criterion you could think of. Any or all of these different variables may line up in any number of ways, and all of the variables may vary independently of one another. "
3 " Fifteen-year-old girls produce children with sixteen-year-old boys in the backseat of cars and in the stairwells of apartment buildings. Why can't two loving adults who have contemplated parenthood and are prepared to offer love, patience, and devotion come up with enough chromosomal matter to stick together and create a child? "
