Judy Rosenkrantz, age 11, of Springfield, Mass. .her question;
Do other animals besides birds lay eggs?
Animals have bean on earth for at least 500 million years and each generation has handed on life to its children. In all this time, the type of animal life has changed many times„ New forms developed. Some forms, like the birds and fishes, succeeded. Some, like the dinosaurs, finally failed. But the style in child bearing did not change until recent times, In the past all mother animals laid eggs and, even in our modern world, most of the animals still lay eggs.
The feathery birds took to the air more than 60 million years ago, Their ancestors were reptiles. Feathers and flight were new ideas, but the birds started to lay eggs as their ancestors had done way back to the dawn of time. Reptiles still use the same method of handing on life to their children. Our lizards and most of our snakes lay eggs. The boa snake keens her eggs inside her body until the young are ready to hatch, the and certain other snakes are said to give birth to live babies.
The amphibians deserted the seas some 250 million years ago. But each generation returned to the water to lay its eggs. The frog, who is a modern amphibian, lives on laud but the mother still lays her eggs in the water. Turtles and crocodiles, toads and salamanders also hatch from eggs.
The insects first braved life on land some 270 million years ago. Some of them took to the air arid became giants with wings four feet wide. They developed many different forms to cope with many different problems But all of them continued to lay eggs as their ancestors had done. The scorpions left the seas some 360 million years ago, but like their sea going cousins the lobsters, they still lay eggs,
The snails and all the world’s assortment of wormy creatures also lay eggs. So do the clams and oysters the squids and all the fishes.
True, many of these eggs are unlike birds, eggs. They have soft shells and many of them are too small for our eyes to see. In most cases, the mother animal leaves her eggs to hatch for themselves and take their chances. Birds, as a rule, are renowned as devoted parents. But these differences do not alter the fact that most of Mother Nature's children lay eggs.
As the dinosaurs declined some 60 million years ago, the new breed of mammals arose. These were the first animals to bear live babies and feed them on mother’s milk. They may have been Somewhat like the strange platypus which lays eggs, curls her furry body around them until they catch and then feeds them on her milk. But the mammals are late comers in the story of life and they are still far outnumbered by the animals that lay eggs.