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About sixty-five million years ago, at the end of the Mesozoic era and the beginning of the Cenozoic, the niche once dominated by the dinosaurs was available for other creatures. The opportunistic could move into that niche now empty of large reptiles, and prosper in their place. Among these creatures that flourished…
Crying evolved to serve the infant's purposes: to assure protection, adequate feeding, and nurturing for an organism that cannot care for itself. By definition, crying is designed to elicit a response, to activate emotions, to play on the empathy of another. The "other" is usually the mother or father or a related…
Crying is the earliest and most compelling of infant signals," writes Ronald Barr, and surely there is no sound on earth more piercing than the cry of an infant. The ability to cry was hard-wired into human babies long ago as a potent signal to get adult attention. Like other primates, human infants needed to be able…
Not all babies are the same. Human babies are rather helpless, interested mostly in food, sleeping, eating, defecating, and comfort. Compare human babies with newborn deer. When fawns are born, they immediately stand up and soon are able to run away from danger. Scientists call these two types of babies in the animal…
Staring at that skull, I was struck by the fact that this ancient child was somebody's baby long ago. Perhaps she was sick, or maybe he e was accident-prone, or perhaps this baby was some predator's dinner. Standing there, I could picture him or her long ago, I, smiling, laughing, and reaching out to grab a mother's…
One, two, three ragged files of Canada geese skim the treetops, preceded and followed by their honking chorus. I freeze in my tracks to watch them pass, heading south, feathers ruffled by the last warm breezes of the season. When their honks have faded into silence, I notice a chill in the air. The spinning planet has…
Spring provides a kind of annual recapitulation of the evolution of life on Earth, an opportunity to celebrate anew the greening of the planet three and a half billion years ago by the first photosynthesizing bacteria. All life—the whole glorious parade along the path—depends upon the photosynthesizers. As spring…
When the first single-celled organisms appeared on Earth, more than 3 billion years ago, they fed upon carbohydrates—sugars—dissolved in the sea. The sugars had their origin in chance chemical reactions. Life, however, multiplied exponentially; one cell made two, two made four, four made eight, and so on. Self…
When I undertook to answer My own 1927 self-questioning: "Why have humans been included In the design of Universe?" My hypothetical answer of 1927 Was, and as yet is: What impresses me most Is the experientially demonstrable fact That all living organisms Other than humans Have some organically integral equipment That…
In the very largest way of looking at planet Earth's socioeconomic-evolution events, we must observe that humans are designed with legs and not roots. Yesterday, humanity developed temporary roots as it cultivated its life-support food root-grown on the land. The metals made possible metal canning of food and…
What's the difference between evolution and engineering? Engineering is the designing of a whole out of parts suited to their individual purposes. Evolution is the process of tiny incremental changes, each making some small or large improvement in the ability of the thing to survive and reproduce. A good engineer…
Different cultures today have evolved different sets of sexual mores, resulting in differences in male and female behavior. In Sweden, a social democracy where women have great economic independence, we see a high degree of sexual freedom among women. Without needing to depend on men for their security, Swedish women…
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…
The sheets of tissue that fold, invaginate and turn inside out in a developing embryo do indeed grow, and it is that very growth that provides part of the motive force which, in origami, is supplied by the human hand. If you wanted to make an origami model with a sheet of living tissue instead of dead paper, there is…
Each individual's genome, in any one generation, will be a sample from the species database. Different species will have different databases because of their different ancestral worlds. The database in the gene pool of camels will encode information about deserts and how to survive in them. The DNA in mole gene pools…
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…
Hermann von Helmholtz, the great nineteenthcentury German scientist (you could call him a physicist, but his contributions to biology and psychology were greater), said, of the eye: 'If an optician wanted to sell me an instrument which had all these defects, I should think myself quite justified in blaming his…
A favourite example, ever since it was pointed out to me by Professor J. D. Currey when he tutored me as an undergraduate, is the recurrent laryngeal nerve.* It is a branch of one of the cranial nerves, those nerves that lead directly from the brain rather than from the spinal cord. One of the cranial nerves, the…
Thus, from the war of nature, from famine and death,* the most exalted object which we are capable of conceiving, namely, the production of the higher animals, directly follows. There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that…