Had Poseidon more carefully measured out whatever it was he gave to Caenis, the matter would not have come to Zeus’ attention. Had Poseidon’s own testosterone titer been lower, or had there been enforceable penalties against gods raping humans, Caenis might have lived a happy and blameless life. As it was, Caeneus was afflicted by hubris, surely; but only because of the rape and its aftermath. He was guilty of disrespect for the gods, but the gods had shown disrespect for her. There is not a hint that the piety of Thessaly would have been troubled had Poseidon left Caenis alone. She had been minding her own business, walking along the beach.
* One of the expert reviewers of this book complains, “I would struggle to help noticing. . You don’t need to be right at armpit level to smell Consider any gym” But gyms are permeated with the accrued perspiration of many athletes over many years. Another expert reviewer notes that molecules like 5-alpha-androstenol are now marketed as alleged aphrodisiacs† Thus, Aristotle’s contention9—echoed millennia later by Sigmund Freud—that “the female is, as it were, a mutilated male” is wrong (Neither is a male a testosterone-altered female, although that’s a little closer to the truth) Women’s bodies do synthesize estradiol, the most potent of the estrogens, from testosterone.* In order, it is conventionally thought, to keep their temperature a few degrees lower than if they were situated inside the body. If the testicles were located within the warm abdomen, sperm cells, it is said, would be sparsely produced and men would be largely sterile. The benefits of external testicles outweigh the risks. But sparrows and scrappy songbirds carry their testes within; and yet, even at the elevated temperatures, their sperm cells seem to be spunky enough Our understanding of why males of some species wear their testes outside, and others inside, seems incomplete.* Exceptions are, in a way, common Male pigeons and doves routinely feed the young a regurgitated “crop milk,” low in sugar, high in fat—just the opposite of the milk of mammals The cock emperor penguin, after incubating the egg for forty days, generates a rich milk in his esophagus When the chick hatches, this is its only food It doubles its weight on Father’s milk and is doing very well by the time the emperor penguin hen returns engorged with tiny shrimp Both sexes of greater flamingos generate a kind of milk which is mixed with their blood and fed to the chicks in the first month of life; each parent provides about a tenth of a liter of this formula each day12 Many animals—wolves, for example—feed their young with regurgitated food, but this is very different from milk* Well, against all sparrow comers. The dominance relationships in the same bit of forest within the communities of, say, owls, bears, raccoons, and humans are generally beneath the notice of sparrows* The question is similar to that posed by the artichoke: Are more calories burned in trying to get to its succulent heart than are afforded by eating the thing?* Just as chicks seem to retain and refine this concern when they get to be adults, so do humans. The fear of non-human predators is another one of our readily available “buttons” that are easy to press in order to manipulate passionate behavior Horror films are one, but hardly the most egregious, example* The sexes differ in other kinds of cries as well For example, when a male comes upon some food he knows the female likes, he often generates a food call. But when the hen finds food, she does not call to the cock; indeed, she does not call at all, unless she has chicks. Hens without families prefer to dine alone.
Chapter 13
THE OCEAN OF BECOMING
Every valley shall be exalted, and every
mountain and hill shall be made low.
Isaiah 40:4
They will manage to cross the ocean of
becoming.
The Maitreyavyakarana (India, about 500 B.C.)1
Let’s for a moment imagine your species is wildly successful. Through the slow evolutionary process it’s become adapted with high precision to its environmental niche. You and all your fellows are now, perhaps even literally, fat and sassy. But, again, especially when you’re so well adapted, any significant genetic change tends not to be in your best interest—just as a random change in some of the microscopic magnetic domains on an audio tape is unlikely to improve the music recorded there. You can’t stop deleterious mutations from happening, just as you can’t prevent a slow degradation of the recorded music, but those mutations are restrained from spreading through the species. Natural selection sifts through the population and quickly disposes of whatever doesn’t work, or doesn’t work as well. It is not considered an extenuating or mitigating circumstance that, by some remote accident, the mutation might be useful in the future. Darwinian selection is for the here and now. Summary judgment is rendered. With careful discrimination, the scythe of selection swings.
But now, let’s imagine that something changes. A small world hurtling through space finds a blue planet smack in its path, and the resulting explosion sprays enough fine particles into the upper atmosphere to darken and cool the Earth; your lake then freezes over, or the savanna vegetation that sustains you shrivels and dies. Or the tectonic engine in the Earth’s interior creates a new island arc and a flurry of volcanic explosions changes the composition of the air, so now more greenhouse gases are released into the atmosphere, the climate warms, and the tidepools and shallow lakes in which you have been luxuriously wallowing begin to dry up—or a dam of glacial ice is breached, creating an inland sea where your congenial desert habitat used to be.
Perhaps the change comes from a biological direction: The animals you eat are now better camouflaged, or defend themselves with greater obstinacy; or animals that eat you have become more adept at the hunt; or your resistance to a new strain of microorganism turns out to be poor; or some plant you habitually eat has evolved a toxin that makes you ill. There can be a cascade of changes—a relatively small physical alteration leading to adaptations and extinctions in a few directly affected species, and further biological changes propagating up and down the food chain.
Now that your world has changed, your once wildly successful species may be reduced to much more marginal circumstances. Now some rare mutation or an improbable combination of existing genes might be much more adaptive. The once-spurned hereditary information may now be given a hero’s welcome, and we are reminded once more of the value of mutation and sex. Or, it may be, no new and more useful genetic information is generated fortuitously in the nick of time, and your species continues its downward drift.
Omnicompetent organisms do not exist. Breathing oxygen lets you be far more efficient in extracting energy from food; but oxygen is a poison for organic molecules, so arrangements for routine handling of oxygen by organic molecules are going to be expensive. The ptarmigan’s white feathers provide superb camouflage in the Arctic snows; but in consequence it absorbs less sunlight and greater demands are placed on its thermoregulatory system. The peacock’s gorgeous tail makes him nearly irresistible to the opposite sex, but also provides a conspicuous luncheon advertisement for foxes. The sickle-cell trait confers immunity to malaria, but condemns many to debilitating anemia. Every adaptation is a trade-off.
Imagine designing a vehicle that drives off roads, flies through the air, and swims underwater. Such a machine, if it could be built at all, would perform none of its functions well. When we need to travel on “unimproved” land we build all-terrain vehicles, when beneath the water, submarines, and when through the air, airplanes. It’s for good reason that these three kinds of vehicles, while roughly of similar shape, in fact tend not to look very much alike. Even so-called “flying boats” are not very seaworthy, nor are they very easy to fly.