Early ideas about the origin of species

Plato 428-348 BC

2 worlds 1 world Real and Perfect The other world Imaginary and Perceived

Aristotle 348- 282 BCE Student of Plato

Scala Natura an ordered ladderof things from the simple to the complex.The species were fixed. We’re near the top.

Diversity of life

Carlos Linaeus (Carl von Linné)1707-1778 Father of taxonomy His life goal was to name and classify all the organisms on earth.He did the ground work of binomial nomenclature

This theory has been disproved!

Lamark 1744-1849 Evolution is driven by “ the innate desire to improve” Use caused the growth of a desired trait. Disuse cause the Deterioration of a trait. These acquired traits could then be inherited.Eg. Duck’s webbed feet, Snakes hips, a giraffe's

neck A blacksmith’s muscles, A concert pianists skill.

Sir Charles Lyell 1797 -1875 Wrote Geologia Principia Or Principles of Geology He determined that the earth was very old.(This was radicle!!)It was billions of years old instead of the biblical thousands. Geology is constantly changing slowly Slow continuous process can bring about a

significant change

CHARLES DARWIN AND THE THEORY OF NATURAL

SELECTIONWho was Charles Darwin?

Darwin as a boy

Charles was born in 1809 on Feb 12 in Shrewsbury, England.He was the fifth of 6 children.

His father and Grandfather were both doctors, very importantAnd to Darwin rather intimidating.

Darwin’s Mother, Susannah died when he was 8 years and he was brought up by his sisters. In his free time he played with insects, identified plants, hiked and hunted and generally liked the outdoors.

His father wanted him to become a doctor but he didn’t study very hard. So he went to get a BA at Cambridge and where he partied and hiked and collected stuff and he almost failed.

As a last resort he was told he had to become a minister of the church. This was the custom in those days.

Charles Darwin at 21

Darwin was spending his last summer Hunting rocks and mountain climbing in Wales before becoming a minister and earning his livelihood.

His professor of theology and botany, Henslow,knew he liked Natural History and Geology

He recommended him to Fitzroy as an unpaid Naturalist for a three Year voyage to map The coast of South America .

Darwin Jumped at the chance against his Father’s will.(Guess who had to pay Darwin’s expenses?)

He was only 21.... He failed at most of his studies and didn’t know what he wanted from life

Captain Fitzroy at 23By 23 Robert Fitzroy was an experienced Sea CaptainWho had already sailed to South America and back on the Beagle.

He wanted company of his own station. There were mental Health issues in his family. He was afraid loneliness might bring on paranoid tendencies. He was very Christian as was Darwin.

His goals were to chart the coast of Patagonia, the worst seas in the world.

He hoped Darwin’s identifying the Flora and Fauna and Geology of the region would help support the “Genesis” version of Creation.

Darwin enthusiastically agreed.

Voyage of the Beagle1831 - 1836

Only 90 Feet in length

Darwin’s Books(and tools)

Lyell’s Principles of Geology, Hot off the press

Von Humbolt’s Personal Narrative (German Naturalist)

Milton’s Paradise Lost. BibleTools:Binoculars, geological hammer, magnifying

glass,Jars of spirits for preserving specimens.

Definitions

Observations: something sensed or measured generally considered a fact.

Inference: an observation + a logical guess

Hypothesis: An Educated guess that is testable.“If this is true , then this will happen.”If the hypothesis is tested and found wrong then it’s thrown out. If it is supported then it’s tested again and again.

Theory: An Hypothesis that has been supported so many times it is

now considered to be true. Often modified in the light of new evidence but rarely thrown out.

Theory of Natural Selection

A theory is a unifying idea that explains observations.

In over 150 years this is still the best explanation for all the evidences of evolution.

Evolution is a slow change over time.It is based on 4 facts and 3 inferences

Fact: Populations left alone will breed exponentially

Fact: Organism produce many more offspring than actually

survive. Most populations are stable except for seasonal flux

Fact:Resources are limited

Inference: Since not all offspring survive, there must be a competition for resources like food, water, sunlight, space. Producing more offspring than the environment can support causes struggle for existence.

Fact: No two individuals in a population are exactly alike.

Inference: Individuals that have a variation that

gives them an advantage in competing for resources will survive longer.

Survival is not random it depends inpart on inherited traits

Inference:

Individuals whose traits best “fit” their environment live longer are more likely to breed and produce more offspring.

More of the successful variations will be passed down to the next generation.

This unequal ability to reproduce will lead to gradual change. Favorable characteristics will accumulate.

In Northern England there is a peppered moths that has two phenotypes.

Dark (dominant) Light (recessive)

Which peppered moth is more likely to be eaten by Blue Jays?

1848’s: before industrial revolution

NO POLLUTION! Trees are covered in lichen

1895’s:after the industrial revolution1

Pollution kills lichen.Trees covered with soot from factories

98% of moths were white2% were black

5% of the moths were white95% were black

Evolution

Evolution is a slow change over time Evolution occurs in a population not in an

individual. We measure evolution by looking at the

change in allele frequencies over time. Just like in the peppered moth. Now with air pollution under control the

lichen is growing back on the tree and the peppered moths have a larger white population again.

Bibliography

Moorehead, Alan. Darwin and the Beagle. third. London: Hamish Hamilton, 1969. 279. Print.

McLaren, James E. et al. Heath Biology. Toronto, Ontario, Lexington , Mass.: DC Heath and Company, 1991. 230-247. Print.

"Charles Darwin." Charles Darwin. Wikipedia, 27 March 2011 at 07:56. Web. 27 Mar 2011. http://en.wikipedia.org/wiki/Charles_Darwin

Kettlewell, Bernard, et al. "Peppered moth evolution." Peppered moth evolution. Wikipedia, 12 March 2011 at 09:36.. Web. 27 Mar 2011. http://en.wikipedia.org/wiki/Peppered_moth_evolution