So there have been found in the rock records more or less complete serial stories of thousands of plants and animals. In the case of man, not only do we find that there were once human beings on earth like the caveman with low forehead and huge jaw, but nothing has ever been found to indicate that there were any higher types of human beings in existence in his day. And both the caveman and the handsomest human beings of to-day—the captain of our football team, for example—have essentially the same bodily framework as the monkey tribe. This does not mean that man—even so low a creature as the caveman—descended from monkeys, any more than the fact that he has a backbone means he descended from humming-birds. But the backbones in humming-birds, monkeys, and men show that all are descended from older types of backboned creatures. As monkeys and men are much more alike than men and birds they are evidently more closely related.
We might suppose, to be sure, that men and all other forms of life which they resemble in any way were so made from the beginning; that is, if we hadn't learned from the records of the rocks that they weren't so made from the beginning. Yet, even after that, we might go on supposing that each species was created separately, but that the form was changed from age to age. But in that case what are you going to say to this:
In man's body are several organs that are useless and often harmful. Other animals, also, contain among useful organs some that are "out-of-date," as we would say if we were speaking of some old machines in a machine-shop. Why, in making a brand-new species, shouldn't Nature have all the latest improvements from the start, just as man does in building a brand-new home? If each species was separately created it is hard to understand why these useless or harmful organs should be kept; but if one species grew out of another, by gradual improvement, just as cities grow out of villages, this is exactly what we might expect.
One of these useless organs in man is called the "vermiform appendix." It is always getting its name in the papers by giving trouble to some prominent man. Now this appendix, while a perfect nuisance to human beings, is just the thing for cows and other grass-eating animals. In them it is very large and of great use in digestion, while in the case of man and the monkey family it has shrunk into a little affair that puts in all its time either doing nothing or getting out of fix.
III. Upward; Always Upward
These are some of the reasons why the various varieties of animals are supposed to have descended from common ancestors and to have undergone endless changes of form; changes as strange as anything that was ever written into a fairy story or acted out in a Christmas pantomime. There are other things quite as convincing and even more thrilling to read about, such as the little theatre in the chicken's egg where strange, changing shadows re-enact the drama of ancient life; but these I am here passing by because my pages are running out and I want the rest of them to speak of what seems to me to be the greatest lesson of this whole book; the greatest and most useful and happiest lesson Science or any kind of book can teach; namely, that not only is the universe governed by Laws and Mind, but that all these laws act together as one Great Law and are working out one general result, the constant advance of all things toward a higher life.
HOW MAN HAS RISEN AS HE DESCENDED
As there was a period in human history when there were no human beings on earth higher than the cave-dweller, so there was a time when the highest forms of animal and vegetable life were minute creatures and plants consisting only of a single cell. It is such low forms of vegetable life that make the scum on the still waters of a pond. Step by step, in both the animal and vegetable world, rose the higher forms. The descent of man from lower forms of life used to be considered by many people as a thought that degraded humanity, but it is the most promising fact in all nature. The striking thing is, not that we are related in some way to the apes and the cavemen but that such a creature as an ape or a caveman should have helped develop such a beautiful thing as a little child.
This progress has not been steadily upward. The world of life, like the surface of the globe itself, has had its ups and downs. Wonderful nations like Greece and Rome have risen and flourished and passed away, but they left the best of themselves, the part that time cannot destroy. The Greeks taught us literature and art and the grace of life. The Romans gave us a science of government and a solid way of doing practical things, such as the building of good roads and bridges. The great lesson of history is that civilization and human liberty and all the things that make life worth living have not only survived the fall of empires but stand to-day on higher and firmer ground than they ever did before.
THE WORLD THAT MOTHER MADE