A little historical background... The idea of evolution was not new in the 1800’s. The idea had been around for centuries. The Church was the authority at the time. It was the Church’s stance that all organisms and their individual structures resulted from the direct act of a creator who formed the entire universe.

Georges Cuvier ( )

Cuvier It was common belief that the world was no older than 5000 years old.

Cuvier’s Fossils Cuvier was a paleontologist and a leading expert on the anatomy of animals. He found that: 1)Each of the layer of rock is characterized by a unique group of fossils 2)The extinction of species is a common occurrence. He proposed the idea of catastrophism.

Catastrophism The theory that catastrophes have periodically destroyed species in a particular region allowing species from neighboring regions to repopulate the area.

John Baptiste Lamark

The Theory of Inheritance of Acquired Characteristics Published in 1809 Proposed: 1)Microscopic organisms arise continually and spontaneously from non-living sources. 2)Each species gradually becomes more complex until they achieve a sort of perfection.

Lamarck continued…. 3)Organisms become progressively better and better adapted to their environments. 4)The characteristics acquired during an organism’s life time could then be passed on to its offspring This theory has been disproved.

Charles Darwin ( )

10 Fun Facts about Darwin 1)Darwin once ate and owl. 2)Darwin wanted to be a doctor but could not stand the sight of blood. 3)Darwin’s nose almost cost him the voyage on the Beagle 4)Best Birthday Gift Ever – A Mountain 5)The full title of his book “Origin of the Species” is actually “The Origin of the Species by means of Natural Selection or Preservation of Favoured Races In the Struggle for Survival”

6) Darwin didn’t coin the phrase “survival of the fittest”. 7)Darwin married his first cousin. 8)Darwin lost his faith in God after his daughter Annie died at the age of 10. 9)Darwin was a backgammon fiend. 10)The Church of England just recently apologized to Darwin for their criticism of him and his theory.

Darwin’s Voyage of Discovery ( ) Darwin was appointed naturalist of the HMS Beagle. The primary mission of the expedition was to survey the coast of South America. Darwin spent hours observing and collecting thousands of specimens in the diverse environments that the ship visited.

The Route Taken by the Beagle

Summary of Darwin’s Evidence Plants and animals observed in the temperate regions of South America were more similar to plants and animals in the South American tropics than to plants and animals in other temperate regions of the world. This lead Darwin to wonder why, if all organisms originated form a single act of creation, there existed a distinctive clustering of similar organisms in different region of the world.

Darwin found fossils of extinct animals that looked very similar to the animals present living in the same region

Summary of Darwin’s Evidence con’t Plants and animals living in the Galapagos Islands closely resembled plants and animals living on the nearest continental coast. This made Darwin wonder why, if all of these organisms had been created independently and been placed in the Galapagos Islands, they so closely resembled organisms on the adjacent South American Coastline.

Summary of Darwin’s Evidence con’t Species of animals that at first looked identical actually varied slightly from island to island in the Galapagos. Finches collected in the Galapagos looked similar to finches from South America but were, in fact, different species. Finch species also varied from island to island. Caused Darwin to wonder why there was such a diversity in such a small area.

The Galapagos Islands

Charles Lyell ( )

Uniformitarianism Charles Lyell was a geologist. Developed the theory known as Uniformitarianism Stated that geological processes operated at the same rates in the past as they do today. Rejected the idea of catastrophism

What Darwin learned by Lyell’s work Darwin read Lyell’s work while aboard the HMS Beagle. After reading his work, Darwin understood that geological processes that are slow and subtle can result in substantial changes. As well, forces that affect change are the same now as in the past. Caused Darwin to wonder why, if the land is always changing/evolving, organisms cannot evolve as well.

EVOLUTION Any shift in a gene pool The relative change in characteristics of populations that occurs over successive generations

Darwin’s Theory of Evolution Darwin was not the first to propose that evolution occurs however he was the first person to gather an array of facts related to evolution and propose a feasible mechanism by which evolution might occur. On July 1, 1858 the idea of Evolution by means of Natural Selection was co-presented by Alfred Russell Wallace and Charles Darwin at a meeting of the Linnaen Society.

The Origin of the Species

On the Origin of the Species On the Origin of the Species was published in In this book, Darwin proposed these 2 main ideas: 1)All present forms of life have arisen by descent by modification from a single ancestral cell. 2)The mechanism for descent is Natural Selection.

Natural Selection The process that drives evolution States that the organisms with traits best suited to their environment are more likely to survive and reproduce.

Summary of Darwin’s Ideas 1)Organisms produce more offspring than can survive, and therefore organisms compete for limited resources. 2)Individuals of a population vary extensively and much of this variation is heritable. 3)Those individuals that are better suited to local conditions survive to produce offspring. 4)Processes for change are slow and gradual.