About Charles Darwin
Charles Darwin was born in England on February 12, 1809. He was a "naturalist," best known for his theories of evolution. Darwin collected evidence that all life on Earth "evolved" from a common ancestry. He studied the process of "natural selection."
Natural selection, or "survival of the fittest," means that organisms best adapted to a certain environment are the ones that survive. For example, thick fur is one thing that helps animals survive in cold environments. Baby animals in cold areas that happened to be born with thick fur were more likely to survive. They would then grow up and often (not always) have babies with thick fur. After millions of years of this process, the only animals left would be the ones with thick fur. This is how nature decides which animals are the fittest to survive.
Darwin was the first to show clear, scientific evidence that this process of natural selection was how organisms on Earth evolved.
Charles Darwin grew up in a family that was well educated and intelligent. Charles was also a curious and intellectual boy. He began his studies in medicine and religion. He was always intrigued by natural science, however, and decided to join an expedition that would allow him to study what he loved most.
In 1831, Charles Darwin joined the crew of a ship called the Beagle. Charles was 20 years old at the time. He couldn’t wait to go! He and his fellow travelers sailed around the world for five years, collecting information about what they saw at each stop.
At that time, most people in England believed that God created the earth in seven days. But, during his trip, Charles read a book about how old rocks were. This got him thinking in a new way. Could the world be as old? If so, it would have taken longer than seven days to create.
Everywhere the Beagle went, Charles began to notice how animals changed in little ways to fit the places in which they lived. The more an animal changed, the better chance they had to survive.
He called this kind of change "adaptation."
When the Beagle reached the Galapagos Islands, Charles decided it was the perfect place to test his ideas. There were many small islands, and each was like a living laboratory in the middle of the sea. He first started to observe finches. The finches that he saw from island to island were all slightly different from each other. They were all finches, yes, but each had changed and "adapted" to better survive on the island that they were living on. How could that be?
The Theory of Evolution
When the Beagle returned to England, Charles continued to figure out how animals "adapted" and "evolved." To evolve, Darwin saw that certain parts of animals and plants changed over many lifetimes. These changes, called "traits," were passed down from the parents to their babies.
So, how did it work? Here is one example: Suppose the only food around was high up in the trees. The animals with the longest necks got more leaves because they could reach higher than the same animals with shorter necks.
The long-necked animals ate better and lived longer than their short-necked friends, so they were able to have more babies. They passed their long-necked trait on to their babies in much the same way your parents may have passed their hair color, eye color, nose shape, etcetera, on to you. This process took millions of years and many families, and after a time, the short-necked animals died off and only the long-necked animals remained. This was Darwin's basic idea behind natural selection and how he formed his theory of evolution.
A scientific "theory" is another word for "guess." Well, it’s more than just a guess. A guess can be a quick answer you'd give to a riddle. A "theory" is an "educated guess" to a scientific question. You first have to ask a scientific question, collect and study facts, often called "data," and come up with an educated guess or theory based on your understanding of the data.
Darwin Publishes His Theories
Darwin spent 20 years studying and writing about adaptation, survival, evolution, and natural selection before he put it all together to form his theory of evolution. Finally, he wrote a book about it called On the Origin of Species. People were excited by Darwin's new idea about how life began. His book became a best seller!
Some people who still felt the world was created in seven days, were scared by Darwin's theory. They were afraid to believe that humans evolved the same way other animals had, because it went against everything they had been told. Years later, Darwin wrote another book called The Descent of Man. In this book,he said people evolved from apes. Talk about being a monkey's uncle! But, over time, people could see he made a strong case for his theories. Today, his theories are generally accepted as fact.