The Evolution of Evolution

Consider… 10:30 pm on December 31: the

first human-like animals emerge Modern-looking humans have only

been around for 100,000 years

Evolution Pre-Darwin

Plato and Aristotle Carolus Linnaeus

(1717-1778)

Jean-Baptiste Lamarck (1744-1829)

Continual adjustment

Ideas were flawed

Lamarck vs. Darwin

Georges Cuvier (1769-1832)

Catastrophism i.e., Noah’s flood

Sir Charles Lyell (1797-1875)

Geological change was slow and continual , not due to catastrophes uniformitarianism

Corresponded with Darwin

Alfred Russel Wallace (1823-1913)

Reached similar conclusions as Darwin

Charles Darwin (1809-1882)

The Voyage of the HMS Beagle1831-1836

Galapagos Islands

The Principles of Natural Selection According to

Darwin1. Variation

The essential underlying feature of evolution

Random mutations create a variety of individuals, some of whom are better suited to the environment

The Principles of Natural Selection According to

Darwin2. Heritability

Offspring inherit characteristics from their parents

The Principles of Natural Selection According to

Darwin3. Differential Reproductive Success

“Natural Selection”

Those who inherit favorable characteristics will thrive

Those who do not will die out

British Moths and Kettlewell’s Experiment

Directional vs. Normalizing Selection

Directional: adaptation toward an adaptive change i.e., the peppered moth

Normalizing: adaptation against extremes i.e., birth weight

Evolution After Darwin

“Punctuated Equilibrium” Stephen Jay Gould

The mapping of the human genome has changed everything Genetic mutation is

not the only element of change

“Switch” Genes