David Almond, age 10, of New London, North Carolina, for his question:

How did the cat family originate?

A few columns ago, we traced back to the origin of the dog family. Now let's see how the cat family got its start. In the modern world, most cats and dogs are not on friendly terms, to say the least. This is strange, because in the dim distant past they were very close kinfolk. In fact, their earliest ancestors could not tell which would become cats and which would become dogs.

Through the long ages of time, the earth's climate and geography have kept changing. Sometimes animals needed warmer coats to cope with an ice age, stronger teeth to chew tougher grasses or longer legs to escape faster foes. Many of them died out. The ones that survived were those that changed themselves, though very, very slowly, to keep up with the changing times.

Scientists trace these changes back through fossil bones left in the ground. The fossil records of the cat family go back 55 million years to the dawn of the age of Mammals that began after the bulky dinosaurs departed. At that time, the original ancestor of the cat family was somewhat like a modern civet. The furry little tree climber had a pointed nose and a very long tail. Scientists named him Miacis and, of all things, this same Miacis also was the ancestor of the dog family and the bear family.

He must have been a remarkable animal, for his offspring had the great talent for survival. They were able to do this because they could change to keep up with the times. What's more, his various offspring changed in different ways and became different branches of the original family. One branch of the dog types led to the bears, though several others became extinct.

The cat family branched off about 35 million years ago. They were true cats, with catty features that endured through the ages. However,. at first there wire two groups in the cat family. All cats, of course, have large canine teeth which they use as knives and forks to tear up their meat. Originally one group of cats had an extra large pair of tusky canines.

As time went on, some of the cats chased larger game and grew bigger. A variety of large and small cats followed their favorite food to different parts of the world. A million years ago, several big cats were larger than modern lions and tigers. One was the huge sabre toothed tiger, with tusky teeth nine inches long. However, the changes after the ice age may have been too much for him. In any case, he became extinct just a few thousand years ago    and so ended the tusky toothed branch of the cat family.

Some scientists suspect that cats have warm fur coats because nature intended them to live in the cold north. But cats, as we know, love comfort. This may explain why most of them moved south to enjoy warmer weather. In any case, various small wild cats were happy to make themselves comfortable by the cozy fires of our ancestors, some 6,000 years ago.