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Find a picture of yourself. Now take a picture of your father and place it on top. Then find a picture of his father, your grandfather. Then place on top of that a picture of your grandfather's father, your great-grandfather. You may not have ever met any of your great-grandfathers. I never met any of mine, but I know…
It's easy to see that predators (animals that kill and then eat other animals) are working for the downfall of their prey. But it's also true that prey are working for the downfall of their .fedators. They work hard to escape bei and it they all succeeded the predators would starve to death. The same thing holds…
The Epic of Gilgamesh is one of the oldest stories ever written. Older than the legends of the Greeks or the Jews, it is the ancient heroic myth of the Sumerian civilization, which flourished in Mesopotamia (now Iraq) between 5,000 and 6,000 years ago. Gilgamesh was the great hero king of Sumerian myth - a bit like…
It is at this point that the ultimate significance of dolphins in the search for extraterrestrial intelligence emerges. It is not a question of whether we are emotionally prepared in the long run to confront a message from the stars. It is whether we can develop a sense that beings with quite different evolutionary…
Flo, inevitably, began to show her age. She wasn't strong enough to wean Flint when the time came, nor to care for her new infant Flame, born when Flint was only four and a half years old (the normal birth interval is five years or more). Flame disappeared during a time when Flo was too ill even to climb into a nest…
The instinct to command others, in its primitive essence, is a carnivorous, altogether bestial and savage instinct. Under the influence of the mental development of man, it takes on a somewhat more ideal form and becomes somewhat ennobled, presenting itself as the instrument of reason and the devoted servant of that…
Let us only imagine that birds had studied their own development and that it was they in turn who investigated the structure of the adult mammal and of man. Wouldn't their physiological textbooks teach the following? 'Those four and two-legged animals bear many resemblances to embryos, for their cranial bones are…
6 Go to the ant, you sluggard; consider its ways and be wise! 7 It has no commander, no overseer or ruler, 8 yet it stores its provisions in summer and gathers its food at harvest.
Evolution is neither moral nor immoral. It just is, and we make of it what we will. I have tried to show that two things we can make of it are that it’s simple and it’s marvelous. And far from constricting our actions, the study of evolution can liberate our minds. Human beings may be only one small twig on the vast…
What keeps members of two related species from mating with each other? There are many different reproductive barriers. Species might not interbreed simply because their mating or flowering seasons don’t overlap. Some corals, for example, reproduce only one night a year, spewing out masses of eggs and sperm into the…
Native Missing Plants Land mammals Birds Reptiles Insects and other Amphibians arthropods (e.g., spiders) Freshwater fish [...] Further, when you look at the type of insects and plants native to oceanic islands, they are from groups that are the best colonizers. Most of the insects are small, precisely those that…
Mayr lived exactly 100 years, producing a stream of books and papers up to the day of his death. Among these was his 1963 classic, Animal Species and Evolution, the very book that made me want to study evolution. In it Mayr recounted a striking fact. When he totaled up the names that the natives of New Guinea’s Arfak…
Take the domestic dog (Canis lupus familiaris), a single species that comes in all shapes, sizes, colors, and temperaments. Every single one, purebred or mutt, descends from a single ancestral species—most likely the Eurasian gray wolf—that humans began to select about 10,000 years ago. The American Kennel Club…
The most famous example of different species filling similar roles involves the marsupial mammals, now found mainly in Australia (the Virginia opossum is a familiar exception), and placental mammals, which predominate elsewhere in the world. The two groups show important anatomical differences, most notably in their…
Vestigial genes can go hand in hand with vestigial structures. We mammals evolved from reptilian ancestors that laid eggs. With the exceptions of the “monotremes” (the order of mammals that includes the Australian spiny anteater and duck-billed platypus), mammals have dispensed with egg-laying, and mothers nourish…
...evolutionary change, even of a major sort, nearly always involves remodeling the old into the new. The legs of land animals are variations on the stout limbs of ancestral fish. The tiny middle ear bones of mammals are remodeled jawbones of their reptilian ancestors. The wings of birds were fashioned from the legs…
Now, we’re not absolutely sure why some species retain much of their evolutionary history during development. The “adding new stuff onto old” principle is just a hypothesis—an explanation for the facts of embryology. It’s hard to prove that it was easier for a developmental program to evolve one way rather than…
Another curious tale of dead genes involves our sense of smell, or rather our poor sense of smell, for humans are truly bad sniffers among land mammals. Nevertheless, we can still recognize over 10,000 different odors. How can we accomplish such a feat? Until recently, this was a completely mystery. The answer lies in…
And the evolutionary prediction that we’ll find pseudogenes has been fulfilled—amply. Virtually every species harbors dead genes, many of them still active in its relatives. This implies that those genes were also active in a common ancestor, and were killed off in some descendants but not in others. Out of about…
Some atavisms can be produced in the laboratory. The most amazing of these is that paragon of rarity, hen’s teeth. In 1980, E. J. Kollar and C. Fisher at the University of Connecticut combined the tissues of two species, grafting the tissue lining the mouth of a chicken embryo on top of tissue from the jaw of a…