Darwin Flashcards
Origin of Species by Means of Natural Selection
Darwin’s book published in 1859 that shook the worldview of Western culture
Darwin’s 2 major points in his book
- Descent with modification explains life’s unity and diversity
- Natural selection is a cause of adaptive evolution
Descent with modification
The idea that organisms presently inhabiting the Earth are descendants of ancestral species.
Aristotle
Viewed species as fixed and unchanging`
Bible’s Old Testament
Stated that species were individually designed by God and therefor perfect
Carolus Linnaeus
Said organismal adaptations are evidence that a Creator designed each species for a specific purpose.
Founded taxonomy
Cuvier
Studied fossils and laid groundwork for Darwin. Believed fossils usually found in sedimentary rock are remains of past organisms, developed paleontology, and introduced the idea of catastrophism
Catastrophism
Each separation between strata (the different layers in sedimentary rocks) were formed by a unique catastrophe (e.g., the great flood, earthquake, etc.)
Gradualism
Profound change can take place through the cumulative effect of slow but continuous processes
Hutton and Lyell
Strongly influenced Darwin. Perceived that changes to Earth’s surface are a result of slow continuous actions still happening today. Presented the concept of gradualism
Lamarck
Hypothesized that species evolve through use and disuse of traits and the inheritance of these traits. (If you exercise a lot and get strong, your child will inherit the strong gene and be strong too).
Charles Darwin
Evolutionary scientist who founded the idea of natural selection
HMS Beagle
A boat that took voyage around the world and allowed Darwin to study adaptations and collect species
Galapagos finches
Darwin observed these finches on his voyage and observed that the diversity of these birds were due to adaptation
Alfred Russell Wallace
Developed a theory of natural selection similar to Darwin’s. He sent Darwin his manuscript of his research and Darwin panicked and hurried and finished his book to become the first founder of natural selection.
Ernst Mayr
Dissected Darwin’s theory and made 3 inferences and 5 observations
Observation 1
For any species, population sizes would increase exponentially if all individuals that are born successfully reproduced
Observation 2
Populations tend to be stable in size
Observation 3
Resources are limited
Observation 4
Members of a population vary in their characteristics (no two individuals are identical)
Observation 5
Much of the variation is heritable
Inference 1
Production of more individuals than the environment can support will lead to many organisms dying
Inference 2
Survival depends in part on inherited traits. Individual with good inherited traits will have a better likelihood of survival and reproduction than someone with bad traits
Inference 3
The unequal ability of individuals to survive and reproduce leads to gradual change in a population. Overtime favorable characteristics with become more common.
This results in adaptation
Artificial Selection
Humans have modified other species over many generations by selecting and breeding individuals that possess desired traits
Natural Selection
Different organisms will have different rates of success in survival and reproduction. This results from heritable traits and the environment.
If an environment changes…
Natural selection will result in adaptation to the new conditions
