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That the universe is expanding was news to Einstein. But the possibility that the galaxies are moving away from each other had been proposed a few years before Hubble's papers on theoretical grounds arising from Einstein's own equations. In 1922, Russian physicist and mathematician Alexander Friedmann investigated…
After sleeping through a hundred million centuries we have finally opened our eyes on a sumptuous planet, sparkling with color, bountiful with life. Within decades we must close our eyes again. Isn’t it a noble, an enlightened way of spending our brief time in the sun, to work at understanding the universe and how we…
One case involves our ability to digest lactose, a sugar found in milk. An enzyme called lactase breaks down this sugar into the more easily absorbed sugars glucose and galactose. We are born with the ability to digest milk, of course, for that’s always been the main food of infants. But after we’re weaned, we…
Still other species have adapted via selection to human-caused changes in their environment. Insects have become resistant to DDT and other pesticides, plants have adapted to herbicides, and fungi, worms, and algae have evolved resistance to heavy metals that have polluted their environment. There almost always seem…
The dog can stand for the success of other breeding programs. As Darwin noted in The Origin, “Breeders habitually speak of an animal’s organization as something quite plastic, which they can model almost as they please.” Cows, sheep, pigs, flowers, vegetables, and so on—all came from humans choosing variants present…
One of the marvels of evolution is the Asian giant hornet, a predatory wasp especially common in Japan. It’s hard to imagine a more frightening insect. The world’s largest hornet, it is as long as your thumb, with a two-inch body bedecked with menacing orange and black stripes. It’s armed with fearsome jaws to clasp…
How have all those exquisite adaptations of one part of the organization to another part, and to the conditions of life, and of one distinct organic being, been perfected? We see these beautiful coadaptations most plainly in the woodpecker and missletoe; and only a little less plainly in the humblest parasite which…
... the cooperative forces are biologically the more important and vital. The balance between the cooperative and altruistic tendencies and those which are disoperative and egoistic is relatively close. Under many conditions the cooperative forces lose, In the long run, however, the group centered, more altruistic…
Is the climate crisis real? Yes, of course it is. Pause for a moment to consider these events of just the past 12 months: • Heat. According to NASA, 2010 was tied with 2005 as the hottest year measured since instruments were first used systematically in the 1880s. Nineteen countries set all-time high temperature…
A third-grade boy comes home and hands his father his report card. His father looks at it and says, “How do you explain these D’s and F’s? The boy looks up at him and says, “You tell me: Is it nature or nurture?” I was once at a lively, noisy science fair with my own third-grade son, and we were touring some of his…
One day I buried myself, prone, in the muck of a muskrat house. While my clothes absorbed local color, my eyes absorbed the lore of the marsh. A hen redhead cruised by with her convoy of ducklings, pink-billed fluffs of greenish-golden down. A Virginia rail nearly brushed my nose. The shadow of a pelican sailed over a…
Many plants new to North America first sprouted up alongside wharves and shipyards. From there they made their way inland along new roads hacked out of the wilderness, and later along canals and railroad embankments, taking up residence in any sort of disturbed soil. Native plants adapted to quiet precolonial forests…
Of course, no one person has the time, knowledge, or skill to learn everything about a landscape, so in my walks 1 have relied upon the labors of generations of botanists, ornithologists, zoologists, geologists, ecologists, meteorologists, astronomers. cultural historians, and a host of other specialists who have…
Caenorhabditis elegans was chosen in the 1960s as an ideal experimental animal by the formidably brilliant South African biologist Sydney Brenner. He had recently completed his work, with Francis Crick and others at Cambridge, on cracking the genetic code, and was looking around for a new big problem to solve. His…
Another familiar example is the sculpting of the wolf, Canis lupus, into the two hundred or so breeds of dog, Canis familiaris, that are recognized as separate by the UK Kennel Club, and the larger number of breeds that are genetically isolated from one another by the apartheid-like rules of pedigree breeding…
New antibiotics have been coming out at frequent intervals since then, and bacteria have evolved resistance to just about every one of them. Nowadays, the most ominous example is MRSA (methycillin-resistant Staphylococcus aureus), which has succeeded in making many hospitals positively dangerous places to visit…
Whales were long an enigma, but recently our knowledge of whale evolution has become rather rich. Molecular genetic evidence (see Chapter 10 for the nature of this kind of evidence) shows that the closest living cousins of whales are hippos, then pigs, then ruminants. Even more surprisingly, the molecular evidence…
It is clear, however, that the cause of homosexuality lies in some unusual balance of hormonal influence in the womb but not later on, a fact that further supports the idea that the mentality of sexual preference is affected by prenatal sex hormones. This is not incompatible with the growing evidence that…
I’ve been thinking of civilization (the technium) as a life form, as a self-replicating structure. I began to wonder what is the smallest seed into which you could reduce the "genes" of civilization, and have it unfold again, sufficient that it could also make another seed again. That is, what is the smallest seed of…
1 In the beginning God created the heavens and the earth. 2 Now the earth was formless and empty, darkness was over the surface of the deep, and the Spirit of God was hovering over the waters. 3 And God said, “Let there be light,” and there was light. 4 God saw that the light was good, and he separated the light from…