Early Ideas about Evolution

James Ussher Archbishop of Ireland in the 17th century Used generations in the bible to fix the date of creation to 4004 B.C. Life was about 6000 years old Creationist God created an infinite & continuous series of life forms All have remained unchanged since creation

Beliefs in the 18th century… Before Darwin, two ideas about life on Earth prevailed… Species are fixed, or permanent. In other words, they do not change. Earth itself is less than 10,000 years old and also relatively unchanging. These ideas were challenged as people became aware of the incredible diversity of organisms, past and present, and the nature of Earth's geologic processes.

Karl Linneaus Precise descriptions of nature Swedish botanist in the 18th century Precise descriptions of nature Purpose – to reveal the unchanging order of life created by God Problem: Noticed that hybrids could be created Designed a logical classification system

George Leclerc Living things change through time French zoologist in the late 18th century Living things change through time Earth must be at least 75,000 years old Species could NOT evolve into other species

Erasmus Darwin Evolution has occurred in living things Humans evolved English physician / amateur scientist in the late 18th century Evolution has occurred in living things Humans evolved

Jean Lamarck New idea on how evolution occurs. French biologist in the 19th century New idea on how evolution occurs. Simple organisms spontaneously arise and inevitably develop into more complex forms Evolution due to the inheritance of acquired characteristics… individuals acquire traits in their lifetimes as a result of experience or behavior, then pass on these traits.

Jean Lamarck Create your own example of Lamarkian evolution.

George Cuvier French anatomist in the early 19th century Reconstructed the appearance of unique organisms from fossil bones. Some organisms from the past different greatly from any living species Fossils in deeper layers of rock were increasing different from living species Some organisms had become extinct

George Cuvier French anatomist in the early 19th century Idea of CATASTROPHISM >> sudden geologic catastrophes caused the extinction of large groups of organisms at certain points in the past. Contributed to scientific acceptance that geologic change and extinction had occurred.

Charles Lyell Uniformintarianism = slower, progressive changes English geologist in the 19th century Uniformintarianism = slower, progressive changes Geologic processes that have changed the shape of Earth’s surface in the past continue to work in the same ways Evidence from geology would contribute to Darwin’s conclusions

Charles Darwin Voyage to collect plants and animals Naturalist in the 19th century Voyage to collect plants and animals Came up with evolution through natural selection based on his observations