达尔文及其理论 英文

Other disciplines ask how?
Evolutionary biology asks why?
Evolution’s Core Principles
Natural selection.
Evolution’s Core Principles
Common descent wit百度文库 modification.
Haeckel: ontogeny recapitulates phylogeny
• Thomas Hunt Morgan: Darwin’s bulldog
Darwin’s Observations and Inferences Organized by Ernst Mayr
Observation 1: Left unchecked, the number of organisms of each species will increase exponentially, generation to generation.
1766-1834
Jean Baptiste de Lamarck – evolution by acquired characteristics. First evolution Theory, Giraffes get taller due to stretching In parents
1744-1829
Working definition: Evolution is the progressive change in populations over time. NOT SPECIES, NOT INDIVIDUALS
Evolution Holds a Unique Place in Biology
Contributor’s to Darwin’s thinking included: Charles Lyell –(geologist) uniformatarianism. The Earth is older than 6,000 years
1797-1875
Georges Cuvier – species extinction. Fossils
1769-1832
Darwin’s Ideas Did Not Develop in a Vacuum
Contributor’s to Darwin’s thinking included:
Thomas Malthus – struggle for existence. Carrying capacity: J curve/S curve
Evolutionary Time Scales
Macroevolution: Long time scale events that create and eliminate species.
Evolutionary Time Scales
Microevolution: Short time scale events (generation-to-generation) that change the genotypes and phenotypes of populations. We’ll begin our more intensive look at evolution with microevolution.
Evolution
Nothing in biology makes sense except in the light of evolution. – Theodosius Dobzhansky Charles Darwin in later years
What is Evolution?
The kind we’re talking about is sometimes called organic evolution to distinguish it from non-biological changes over time.
Observation 5: Much of this variation between individuals is heritable.
Observation 2: In nature, populations tend to remain stable in size.
Observation 3: Environmental resources are limited. Inference 1: Production of more individuals than can be supported by the environment leads to a struggle for existence among individuals, with only a fraction of offspring surviving in each generation.
Darwin’s Observations and Inferences
Observation 4: Individuals of a population vary extensively in their characteristics with no two individuals being exactly alike.
Alfred Russel Wallace Independently Drew the Same Conclusions as Darwin
Papers from Wallace and Darwin were jointly presented (with little impact) to the Linnaean Society in 1858.
Darwin’s Voyage of Discovery
A reconstruction of the HMS Beagle sailing off Patagonia.
The Voyage of the Beagle
Darwin’s Ideas Did Not Develop in a Vacuum