Influences on Darwin

Common Beliefs During the 1800’s The Earth was very young – 4,000 years or less. All things on the Earth had been present since creation and remained unchanged.

Four Important Theories Each of these ideas challenged a young, static Earth James Hutton’s Geological Change Charles Lyell’s Principles of Geology Jean-Baptiste Lamarck’s Evolution Hypotheses Thomas Malthus’ Population Growth

Hutton and Lyell’s Work Hutton proposed that layers of rock form very slowly and are moved and changed by natural phenomena Lyell challenged scientists to explain changes in terms of visible natural phenomena.

Hutton & Lyell’s Influence on Darwin Both geologists showed that the Earth was much older than 4,000 years. Darwin wondered how life on Earth changed during the longer period of time

Lamarck’s Theory of Evolution The first proposed theory of evolution. Animals try to survive in their environment As they use certain parts of their body, the part becomes more suited to the environment This new, better trait is passed on.

Problems with Lamarck Behaviors do not affect inherited traits. Examples: Baseball player- Motorcyclist-

Malthus’ Population Growth Humans were having babies faster than people were dying. This would cause uncontrolled population growth. The only forces that would stop the growth were war, famine and disease.

Malthus’ Influence on Darwin Darwin noticed that most organisms reproduce much faster than humans, but don’t over run the world. Most die or fail to reproduce What causes some organisms to survive when others die?