Rare Letters by Indira Gandhi
The First Living Things
We saw in our last letter that for a long time the earth must have been too hot for any living things to exist on it. When did life begin on the earth and what were the first living things? That is a very interesting question but it is also a very difficult question to answer. Let us first consider what life is. You will probably say that men are living beings and so are all animals. What about trees and shrubs and flowers and vegetables? Surely they are living also. They grow and drink up the water and breathe the air and die. The chief difference between a tree and an animal is that the tree does not move about. If you remember, I showed you some plants in Kew Gardens in London. These plants--orchids and pitcher plants--actually eat flies. Then there are some animals, like sponges, which live at the bottom of the sea and do not move about. Sometimes it is very difficult to say whether a thing is an animal or a plant. When you study botany, the science which deals with plants, or zoology, the science of animals, you will see these strange things which are neither wholly animal nor plant.
Some people tell us that even stones and rocks have some kind of life and that they feel a kind of pain. But it is difficult to see this. Perhaps you remember a gentleman who came to see us in Geneva. His name is Sir Jagadish Bose. He has shown by experiments that plants have a great deal of life, and he thinks that even stones have some life.
So you see it is not easy to say what thing is living and what is not. But let us leave out stones for the present and consider only plants and animals.
We have today a vast number of living things. They are of all kinds. There are men and women, and some of them are very clever and some are fools. Then there are animals and among them too you find clever animals like the elephant or monkey or ant; you find also animals who are very stupid. Fishes and many other things in the seas are lower down still in the order of life. And right at the bottom of this order you find sponges and jelly-like fishes and those things which are half animal and half plants.
We have to try to find if all these different kinds of animals suddenly came into existence at one and the same time or gradually one by one. How are we to find this ? We have no regular books of those ancient times. But can our book of nature help us? It does help. We find in the old rocks bones of animals. These are called fossils, and when we find them we can say that when that rock was formed long, long ago, the animals whose bones we have found must have lived. You saw many fossils of this kind, big and small, at the South Kensington Museum in London.
When an animal dies, his soft and fleshy parts go bad very quickly but his bones remain for a very long time, and it is these bones that we find and which tell us something of those animals of far-off days. But suppose an animal has no bones like the jellyfish. It will leave nothing behind when it dies. When we examine the rocks carefully and collect all the old fossil bones that we find, we can see that different kinds of animals lived at different periods. They did not all come together from nowhere. At first, there are very simple animals with shells- shellfish for instance. The beautiful shells you pick up at the seaside are all the bony coverings of animals who have died. Later, we find more complicated animals: snakes, enormous beasts bigger than our elephant, and birds and animals resembling those we have today. Last of all, we find remains of man. So it appears as if there was a certain order in the appearance of animals-at first the simplest animals, then a higher type of animal getting more and more complicated till we reach what is called now the highest type of animal- man. How the simple sponge and shellfish developed and changed and improved themselves so much is a most interesting study, and perhaps some day I shall tell you about it. But at present we are concerned with the first living things.
Probably the first living things when the earth cooled down were soft jelly-like substances without any shell or bones, living in the sea. We have no fossil remains of these because they had no bones and so we have to guess more or less. There are many jelly-like things like these in the sea even today. They are round but their shape is continually changing as there is no bone or shell. They are something like this:
You will notice the spot in the centre. It is called the nucleus and it is a kind of heart. These animals, or whatever they are, have a curious way of dividing and becoming two. They start getting thinner at one place and go on doing so till they break off into two jelly-like things and both of these are just like' the original one. This division takes place after this fashion:
You will see that the nucleus or heart also divides and each part gets a bit of it. In this way these animals go on dividing and increasing.
Something of this kind must have been the first living thing on this earth of ours. What a simple and humble representative of life it was! There was nothing better or higher in the whole earth then. The real animals had not come and man was not to come for millions of years.
These jelly-like thinks were followed by seaweeds and shellfish and crabs and worms. Then came fishes. We know a lot about these as they had hard bony parts or shells and they left these for us to find, so long after them, and to study them. The shells were left in the mud on the sea-floor. They were covered up by fresh mud and sand and so were preserved carefully. The mud became hard because of the weight and pressure of the sand and mud on top of it. It became so hard that it became a rock. In this way rocks were formed at the bottom of the sea.
An earthquake or something else brought out the rock from under the sea and it became dry land. Then the dry rock was washed away by the rivers and by rain, and the shells which had been hidden in it for ages and ages came out. This is how we come across these shells or fossils, and after studying them find out what our earth was like in the old days before man came.
We shall consider in the next letter how these simple animals developed and became what they are today.
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