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One hundred million years ago, an ammonoid lived in the sea that then separated India from Asia. It died and fell into limy sediments on the seafloor. These sediments grew deeper and hardened into rock. The shell calcified, becoming part of the rock, though maintaining every detail of its structure. India was on the…
Man has been here 32,000 years. That it took a hundred million years to prepare the world for him is proof that that is what it was done for. I suppose it is. I dunno. If the Eiffel tower were now representing the world's age, the skin of paint on the pinnacle-knob at its summit would represent man's share of that…
Among the scenes which are deeply impressed on my mind, none exceed in sublimity the primeval forests undefaced by the hand of man; whether those of Brazil, where the powers of Life are predominant, or those of Tierra del Fuego, where Death and Decay prevail. Both are temples filled with the varied productions of the…
A famous experiment in high school physics involves putting an electric buzzer in a bell jar, a glass container from which the air can be removed by a pump. When the air is removed, the sound of the buzzer disappears. As early as the seventeenth century, it was recognized that sound needed some medium to travel in. In…
Almost 1000 years ago, Chinese astronomers observed a new star visible in the daytime sky, which they called a “guest star.” This supernova created what we now observe telescopically as the Crab Nebula. It is interesting that nowhere in Western Europe was this transient object recorded. Church dogma at the time…
Recently, President Bush declared the vast ocean and archipelago known as the Northwestern Hawaiian Islands as a national monument. At 1,400 miles long and 100 miles wide, the site is loo times larger than Yosemite National Park, larger than forty-six of the fifty states, and home to more than 7,000 marine species…
But why, it has been asked, did you go there [the Antarctic]? Of what use to civilization can this lifeless continent be? ... [Earlier] expeditions contributed something to the accumulating knowledge of the Antarctic ... that helps us thrust back further the physical and spiritual shadows enfolding our terrestrial…
The fascination of any search after truth lies not in the attainment, which at best is found to be very relative, but in the pursuit, where all the powers of the mind and character are brought into play and are absorbed by the task. One feels oneself in contact with something that is infinite and one finds joy that is…
Here's a riddle for the kids. A man leaves his house for a walk. He walks a mile due south, a mile due east, and a mile due north, and finds he is back where he started. What is the man's name? Yes, Virginia, his name is Santa Claus. And his house is at the North Pole. But don't go looking for him there, Virginia…
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…
Some individuals find the absence of a dialogue distressing – as if meaningful dialogues were commonplace on this planet. Philip Morrison, of the Massachusetts Institute of Technology, has pointed out that such cultural monologues are entirely common in the history of mankind; that, for example, the entire cultural…
The Solar System is much vaster than the Earth, but the speeds of our spacecraft are, of course, much greater than the speeds of the sailing ships of the fifteenth and sixteenth centuries. The spacecraft trip from the Earth to the Moon is faster than was the galleon trip from Spain to the Canary Islands. The voyage…
Just as some species are more similar than others and are placed in the same family, so there are also families of languages. Spanish, Italian, Portuguese, French and many European languages and dialects such as Romansch, Galician, Occitan and Catalan are all pretty similar to each other; together they're called…
美(beautiful) plus 国(kingdom) = 美国
M-theory is not a theory in the usual sense. It is a whole family of different theories, each of which is a good description of observations only in some range of physical situations. It is a bit like a map. As is weU known, one cannot show the whole of the earth's surface on a single map. The usual Mercator…
True, breeders haven’t turned a cat into a dog, and laboratory studies haven’t turned a bacterium into an amoeba (although, as we’ve seen, new bacterial species have arisen in the lab). But it is foolish to think that these are serious objections to natural selection. Big transformations take time—huge spans of it. To…
Modern horses, which descend from smaller, five-toed ancestors, show similar atavisms. The fossil record documents the gradual loss of toes over time, so that in modern horses only the middle one—the hoof—remains. It turns out that horse embryos begin development with three toes, which grow at equal rates. Later…
This is where the prediction comes in. If there were lobe-finned fishes but no terrestrial vertebrates 390 million years ago, and clearly terrestrial vertebrates 360 million years ago, where would you expect to find the transitional forms? Somewhere in between. Following this logic, Shubin predicted that if…
Professor Ayrton said that we were gradually coming within thinkable distance of the realization of a prophecy he had ventured to make four years before, of a time when, if a person wanted to call to a friend he knew not where, he would call in a very loud electromagnetic voice, heard by him who had the…
If any person thinks the examination of the rest of the animal kingdom an unworthy task, he must hold in like disesteem the study of man. For no one can look at the elements of the human frame—blood, flesh, bones, vessels, and the like—without much repugnance. Moreover, when anyone of the parts or structures, be it…