Who Discovered Natural Selection? by Anna Claybourne

Author:Anna Claybourne
Language: eng
Format: epub
ISBN: 9781625133137
Publisher: Britannica Digital Learning
Published: 2015-02-19T00:00:00+00:00

Flowers attract bees, which collect nectar from them, using their long tongues. They also collect pollen on their legs. The bees carry pollen from flower to flower, pollinating the plants, so they can produce seeds. Darwin wondered how it could be that two living things could develop to depend on each other in this way.

• Very different creatures all had similar bodies. For example, humans, birds, bats, and lizards all had a backbone, ribs, four limbs, two eyes, and so on. Had they all developed from one original type of animal?

Nature selects

Darwin was especially interested in selective breeding and how breeders selected the qualities they wanted in their animals. Was something like this happening in nature?

Darwin exchanged letters with many selective breeders. One was William Bernhard Tegetmeier, a leading authority on poultry. In an 1856 letter, Darwin asked for samples of different breeds: “I should be glad of anything . . , which you consider a distinct breed. I should be willing to go to 5s [5 shillings—half a dollar, or 25 p today] per bird.”

Human struggles

Darwin was also influenced by the work of a British philosopher, Thomas Robert Malthus. His most famous work was An Essay on the Principle of Population, which he published first in 1798. In it, he said that when the human population increased, people had to struggle for food and work. The weakest and poorest often died young or were swept away by famines and disease.

Darwin saw that this could apply to all living things. Animals often had too many young and most plants made too many seeds for them all to survive. What was special about the survivors? They must be selected—by nature.

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