HISTORY OF EVOLUTIONARY THOUGHT From Paganism to Darwin and Beyond

WHAT IS EVOLUTION? ► The change of species over a period of time

WHAT IS YOUR OPINION? Please write down the answers to the following questions in your notes. ► Cheetahs can run faster than 60 miles/hour when chasing prey. How would a biologist explain how this ability evolved in cheetahs assuming their ancestors on average ran 20 miles/hr? ► Cave salamanders are blind (their eyes are non- functional). How could a biologist explain how this inability evolved from sighted ancestors?

PRE-DARWIN IDEAS ► Earth is young ► Earth is not changing

HISTORY: In the beginning… Plato and Aristotle (mid 300 B.C.) ► Scale of Nature

EVIDENCE FROM GEOLOGY James Hutton ► He proposed the theory of uniformitarianism ► Earth was formed entirely by slow-moving processes, such as erosion and sedimentation, and that these slow forces continue to shape the landscape. Charles Lyell ► 1830 wrote Principles of Geology that Darwin read on his journey supporting Hutton’s work

JUDEO CHRISTIAN CULTURE Exploring God’s work ► Carlos Linnaeus (1700s): Taxonomy ► George Cuvier (late 1700s): - Paleontology: Found that fossils were dissimilar to modern life - Paleontology: Found that fossils were dissimilar to modern life - Species can become extinct - Species can become extinct - Species can change over time - Species can change over time

► Giant sloth did not resemble modern day sloth

Erasmus Darwin ► Grandpa! ► Termed evolution ► Life developed from a single sources ► Humans close to primates (how dare he!)

O.K. SPECIES EVOLVE BUT WHAT MAKES THEM EVOLVE? MECHANISMS BEHIND EVOLUTION Jean Baptiste Pierre Antoine de Monet, Chevealier de Lamarck…a.k.a. Lamarck! ►P►P►P►Published in 1809 when baby Darwin was born ►L►L►L►Looked at fossil record and role of environment ►I►I►I►Idea #1: use and disuse ►I►I►I►Idea #2: inheritance of acquired characteristics

LAMARCK’S IDEA

Charles Darwin ( ) ► Beagle voyage around the world ► Looked at living organisms and fossil record

VOYAGE ON THE BEAGLE

PATTERNS IN DIVERSITY 1. Species vary Globally Rheas in South America Emu in AustraliaOstrich in Africa

Darwin questioned why are marsupials only found in Australia even though Europe had a similar environment.

Unique South American Character ► A South American tropical lizard more similar to a S.A. desert lizard than another lizard elsewhere

2. Species Vary Locally ► What does the difference in structure between the two tortoises tell you about the island they occupy? Galapagos Tortoises

3. Species vary over time ► Ancestor of armadillo was much bigger

► Darwin also observed on his journey the geological process Hutton and Lyell also observed ► He witnessed earthquakes, changing landscapes ► He found marine fossils high up in the mountains of the Andes in Chile

Working towards a theory of Natural Selection ► Malthus’ work: population size can increases exponentially but it remains stable over time…why?

3 Points To Darwin’s Theory ► 1. There is a struggle for existence

2. Role of the Environment: Natural Selection ► There is variation in a population

The environment plays a role in ► keeping populations in check ► Natural selection is the process of selecting for a variation that is best suited to its environment ► “Survival of The Fittest”: those that can survive and reproduce the most viable offspring are the most fit

3. Descent with Modification

Alfred Wallace ( ) ► I have this theory about natural selection charlsey boy, what do you think? Darwin’s Origin of Species ► Decent with modification (evolution) ► Natural Selection ► Decent of Man was also then published

Lamarck vs. Darwin

► Did your ideas reflect Darwin or Lamarck’s ► What does modern day genetics support? Evolution of Hummingbirds ► _s_4.html _s_4.html _s_4.html