Early ideas about evolution What is evolution? What is evolution? It is the process of biological change by which descendants come to differ from their.

Early ideas about evolutionEarly ideas about evolution What is What is evolutionevolution?? It is the It is the process of biological changeprocess of biological change

by which descendants come to differ by which descendants come to differ from their ancestors.from their ancestors.

Evolution is an attempt Evolution is an attempt to explain the origins of to explain the origins of living things, including humans.living things, including humans.

Early yearsEarly years Much of today’s understanding of Much of today’s understanding of

evolution is based on evolution is based on Charles Charles DarwinDarwin..

What do you think about when What do you think about when you hear his name?you hear his name?

The father of modern evolutionThe father of modern evolution Images of monkeys turned to Images of monkeys turned to

menmen A universe unguided by any A universe unguided by any

divine handdivine hand A view of life that is always A view of life that is always

changingchanging

Early years- 1700’sEarly years- 1700’s

LinnaeusLinnaeus developed developed both a both a binomial binomial system for naming system for naming organismsorganisms and a and a hierarchy of hierarchy of classificationclassification groupings. groupings.

Taxonomy Taxonomy originated in the originated in the work of Linnaeus.work of Linnaeus.

Cuvier, Fossils, and Cuvier, Fossils, and CatastrophismCatastrophism

Fossils are remnants or impressions of organism Fossils are remnants or impressions of organism laid down in sedimentary rockslaid down in sedimentary rocks

FossilsFossils from strata of different ages reveal that a from strata of different ages reveal that a succession of organisms has existedsuccession of organisms has existed on earth. on earth.

CuvierCuvier is considered the father of paleontology. is considered the father of paleontology. Advocating Advocating catastrophismcatastrophism, he maintained that , he maintained that

the differences he observed in the fossils found the differences he observed in the fossils found in in different strata were the result of local different strata were the result of local catastrophic eventscatastrophic events such as floods or drought such as floods or drought and were and were notnot indicative of evolutionindicative of evolution..

Geologic gradualismGeologic gradualism

GradualismGradualism, result of a , result of a slow continuous slow continuous processprocess, was proposed by , was proposed by James James HuttonHutton in 1795 to explain the geologic in 1795 to explain the geologic state of the earth. state of the earth.

DarwinDarwin took the ideas from the took the ideas from the observations of Hutton: The Earth must observations of Hutton: The Earth must be very old if geologic change is slow be very old if geologic change is slow and gradual, and and gradual, and very slow processes very slow processes can produce substantial change.can produce substantial change.

Thomas Thomas MalthusMalthus

1798 published 1798 published Essay on the Principle Essay on the Principle of Populationof Population

gave Darwin idea that populations gave Darwin idea that populations produce more offspring than can produce more offspring than can survive because populations increase survive because populations increase faster than earth can support faster than earth can support

LamarckLamarck LamarckLamarck published a published a

theory of evolutiontheory of evolution in in 1809 (same year Darwin 1809 (same year Darwin was born). He explained was born). He explained the mechanism of the mechanism of evolution with two evolution with two principles.principles.

the the use or disuse of body use or disuse of body parts leads to their parts leads to their development or development or deteriorationdeterioration, , acquired acquired characteristics can be characteristics can be inheritedinherited..

Charles Lyell Charles Lyell

Proposed geological theory of Proposed geological theory of uniformitarianismuniformitarianism which is different from which is different from catastrophism.catastrophism.

Uniformitarianism- the events in the past Uniformitarianism- the events in the past that formed the Earth are still at play that formed the Earth are still at play today and are a gradual processtoday and are a gradual process

Principles of Geology Principles of Geology was published, was published, Darwin read and agreed with the Darwin read and agreed with the findings.findings.

Charles Lyell ContinuedCharles Lyell Continued

He studied sedimentary rock and how the He studied sedimentary rock and how the layers (strata) of the Earth form.layers (strata) of the Earth form.

He said that these processes take thousands He said that these processes take thousands of years to occur.of years to occur.

Darwin used this information to conclude that Darwin used this information to conclude that if the different layers of the Earth take if the different layers of the Earth take thousands of years to form, then the different thousands of years to form, then the different fossils found in each layer must’ve taken fossils found in each layer must’ve taken thousands of years to change or evolve. thousands of years to change or evolve.

Charles Lyell Cont.Charles Lyell Cont.

Voyage of the BeagleVoyage of the Beagle

Darwin was 22 years old when he sailed from Darwin was 22 years old when he sailed from Great Britain on the Great Britain on the H.M.S. Beagle H.M.S. Beagle in 1831.in 1831.

He spent the voyage collecting thousands of He spent the voyage collecting thousands of specimens of the fauna and flora, observing specimens of the fauna and flora, observing various adaptations of organisms. He was various adaptations of organisms. He was particularly struck by the uniqueness of the particularly struck by the uniqueness of the fauna of the fauna of the Galapagos IslandsGalapagos Islands

Darwin and WallaceDarwin and Wallace

In the 1830’s Darwin starts compiling his In the 1830’s Darwin starts compiling his work and another scientist, Alfred work and another scientist, Alfred Wallace, was also working on a theory of Wallace, was also working on a theory of natural selection.natural selection.

Before publishing his findings, Wallace Before publishing his findings, Wallace sends a copy of his work to Darwin in sends a copy of his work to Darwin in 1858.1858.

To Darwin’s surprise, Wallace has To Darwin’s surprise, Wallace has formulated a very similar theory!formulated a very similar theory!

Both findings were presented to the Linnaean Both findings were presented to the Linnaean Society in 1858.Society in 1858.

Darwin’s Darwin’s Origin of Species Origin of Species was published in was published in 1859 (yes! 20 years after he wrote it!), 1859 (yes! 20 years after he wrote it!), Wallace will continue his travels and research Wallace will continue his travels and research

Wallace’s theory and name will forever stand Wallace’s theory and name will forever stand in the shadow of Darwin and the theory of in the shadow of Darwin and the theory of evolutionevolution

Best Seller!Best Seller!

Darwin’s book was a success, however, Darwin’s book was a success, however, natural selection was still questioned even natural selection was still questioned even by Darwinistby Darwinist

In 1865 Mendel’s findings on heredity In 1865 Mendel’s findings on heredity were publishedwere published

However, it would take until the 1900’s However, it would take until the 1900’s before the findings were revisitedbefore the findings were revisited

Charles Darwin dies in 1882 and is buried Charles Darwin dies in 1882 and is buried in Westminster Abbeyin Westminster Abbey