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To ANYONE who has been in space and experienced its changelessness, the real excitement of space flight comes when it is time to land on a new planet. The ground speeds backward under you as you catch glimpses of land and water, of geometrical areas and lines that might represent fields and roads. You become aware of…
Pelorat said, "Tortoises are cold-blooded. Terminus doesn't have any, but some worlds do. They are shelled creatures, very slow-moving but long-living.” "Well, then, isn't it better to be a human being than a tortoise; to move quickly whatever the temperature, rather than slowly? Isn't it better to support high-energy…
What, then, is the difference between human and other animals? Are their bodies made differently? As a matter of fact they are remarkably similar. Cat and dog bodies are used in premedical anatomy studies due to the similarity of structures with identical name and function. Is it that they just can't experience pain?…
Now we come to a facet of human relaxation that is inescapable. The relationship of mind to body, or the psychosomatic nature of humans. The mind and body are interacting, one helping or hindering the other. It is probably impossible to relax the body completely if the mind is under tension. Vice versa, it is…
Animals in second-stage labor, then, act, look, and breathe as though they are having a bowel movement. So what should your wife do after her cervix is completely open and the baby begins to slip through? She should do the same thing. Now, here again, we run into the minor structural differences between humans and…
What a piece of work is the mammalian skeleton. I don't mean it is beautiful in itself, although I think it is. I mean the fact that we can talk about 'the' mammalian skeleton at all: the fact that such a complicatedly interlocking thing is so gloriously different across the mammals, in all its parts, while…
In 1917 the great Scottish zoologist D'Arcy Thompson wrote a book called On Growth and Form, in the last chapter of which he introduced his famous 'method of transformations'. * He would draw an animal on graph paper, and then he would distort the graph paper in a mathematically specifiable way and show that the form…
But people often ask, what is the use of learning all this? If you do not feel by this time how delightful it is to fill your mind with beautiful pictures of nature, perhaps it would be useless to say more. But in this age of ours, when restlessness and love of excitement pervade so many lives, is it nothing to be…
Look at a single tall tree standing proud in the middle of an open area. Why is it so tall? Not to be closer to the sun! That long trunk could be shortened until the crown of the tree was splayed out over the ground, with no loss in photons and huge savings in cost. So why go to all that expense of pushing the crown…
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…
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…
If you go back far enough, everything lived in the sea - watery, salty alma mater of all life. At various points in evolutionary history, enterprising individuals from many different animal groups moved out on to the land, sometimes eventually to the most parched deserts, taking their own private sea water with them…
The first Australopithecine to be discovered, and the type specimen of the genus, was the so-called Taung Child. At the age of three and a half the Taung Child was eaten by an eagle. The evidence is that damage marks to the eye sockets of the fossil are identical to marks made by modern eagles on modern monkeys as…
Textbooks of biology repeat time and again that DNA is a 'blueprint' for building a body. It isn't. A true blueprint of, say, a car or a house embodies a one-toone mapping from paper to finished product. It follows from this that a blueprint is reversible. It is as easy to go from house to blueprint as the other way…
What is remarkable about the starlings' behaviour is that, despite all appearances, there is no choreographer and, as far as we know, no leader. Each individual bird is just following local rules. The numbers of individual birds in these flocks can run into thousands, yet they almost literally never collide. That is…
Zoologists have traditionally divided the vertebrates into classes: major divisions with names like mammals, birds, reptiles and amphibians. Some zoologists, called 'cladists',* insist that a proper class must consist of animals all of whom share a common ancestor which belonged to that class and which has no…
1 Humans deliberately choose attractive roses, sunflowers etc. for breeding, thereby preserving the genes that produce the attractive features. This is called artificial selection, it's something humans have known about since long before Darwin, and everybody understands that it is powerful enough to turn wolves into…
Mankind is a self-domesticated animal; a mammal; an ape; a social ape; an ape in which the male takes the initiative in courtship and females usually leave the society of their birth; an ape in which men are predators, women herbivorous foragers; an ape in which males are relatively hierarchical, females relatively…
If sex had no cost, hummingbirds would not exist. Hummingbirds eat nectar, which is produced by flowers to lure pollinating insects and birds. Nectar is a pure gift by the plant of its hard-won sugar to the hummingbird, a gift given only because the hummingbird will then carry pollen to another plant. To have sex with…
It is my contention that man is just like an ibis or a swallow or a sparrow in several key respects. He lives in large colonies. Males compete with one another for places in a pecking order. Most males are monogamous. Polygamy is prevented by wives who resent sharing their husbands lest they also share his…