Week 1 Lectures Flashcards
What is Evolution?
what is the principle that drives evolution?
The pattern of evolution is change over time due to descent with modification from common ancestors. The principle that drives this is natural selection
Why do we study evolution?
- to learn about biological diversity and historical relationships between organisms
- To understand the processes that drove this diversity and adaptation
- To make informed decisions about medicine, agriculture, and the environment
Define Theory
Statement of what is held to be general laws/principles of something that is known or observed
What are the components of a scientific theory?
- statement of fact: a claim about a pattern that exists in nature
- statement of process: identifies the mechanism responsible for producing pattern
What 2 fundamental observations did Charles Darwin help to explain?
- there was an extraordinary diversity of life
2. many organisms seemed to be well adapted to their environment
Define Adaptation
biologists use this term to refer to a trait/characteristic that increases fitness relative to the organism without the trait
The three early theories of evolution
- Essentialism: each form has a perfect essence, and variation is due to imperfections
- special creation: species are changing, the role of science is to understand god’s plan. (e.g. Carolus Linnaeus, father of taxonomy)
- Uniformitarianism: came from geology, processes operate in past and present, observations of past are due to present mechanisms
Jean-Baptiste Lamarck
came up with the idea of “transformism”-that lineages change from one form to another. Individuals, rather than species as a whole, evolve from one generation to the next (e.g., giraffes)
Thomas R. Malthus
Essay on populations; nation’s food productions led to population well being. this was temporary b/c of population growth, which led back to problems with food
Charles Lyell
Principles of Geology: popularized uniformitarism: the processes that shaped old Earth are still at work today
Charles Darwin and the HMS Beagle
Set off because the capt. wanted his esteemed company. was given Lyell’s manuscript which made him think about evolution
natural selection
A difference on average of survival or reproduction in individuals with certain traits compared to others with different traits
Evolution by natural selection
- Individuals within a populations vary
- variations within a population are passed on from parent to offspring
- in every generation, some individuals are better at reproducing than others
- survival and reproduction of individuals are not random, but are tied to variation
Alfred Russell Wallace
had an independent conception of natural selection.in 1858, both Darwin and Wallace presented their ideas to the Linnean London Society.
On the origin of species by Charles Darwin (1859=published)
- talked about descent with modification
2. natural selection
