"For millennia, evolution has been shaping human genes for a single purpose - reproduction. Those who didn't measure up didn't reproduce. Evolution is a harsh mistress. Genes that helped animals make more of themselves survived.
"At the moment of conception each of us is given that legacy - helices full of genes as old as life itself. Genes that brought fish from the dark into the light, genes that made lizards strong, genes that allowed apes to stand up, genes that crushed others and forged a living from their remains, genes that will write poetry and explore constellations, genes that will stare and the stars and wonder, and genes to make us care about all of it, A genomeful of genes."
Lousy Sex is the title of a book by immunologist Gerald N. Callahan, subtitled Creating Self in an Infectious World, which explores the role of genetics in our lives and our mortality. His collection of essays blending personal history with scientific discoveries and philosophical musings challenges our conventional definitions of self, evolution, and mortality.
In the concluding section of the book, titled "This Is Not The End," Callahan confronts the existential question facing a fast-growing segment of the human population -- seniors past the age of reproduction no longer contributing to the gene pool: what's our purpose? He suggests that language, the ability to share knowledge from beyond the grave, was a evolutionary game-changer. "Once we spoke, we took a first step toward immortality and a non-Darwinian way of evolving," he writes, "There had never been anything quite like language, and those who spoke it spread. Along with that spread there was abruptly a selective advantage to longer-lived humans."
And then there's the question of our mortality, which preachers and teachers have convinced us is our lot in life.
"In truth, we've been lied to," Callahan says. "Death is not an essential element of life. Very long-lived and even large immortal beings do just fine on this Earth. That means that what stands between us and immortality isn't some unbreakable law of nature. We grow old and die because of nothing more than our profligate past and our genetic heritage. At the beginning of the twent-first century. we can change our genes almost as easily as we change our jeans. If we wish to reach for the golden ring of old age, perhaps even immortality, all we need to do is figure out which of our genes are killing us."