PRESENTATION OUTLINE
When Charles Darwin was younger he collected plants and animals while sailing around the world on the "Beagle." His discoveries would lead to his theory of evolution. He also wrote many books one being "Origin of Species."
Charles Darwin was a naturalist and a scientist.
Charles Darwin is given credit for discovering that natural selection was the agent for the transmutation of organisms during evolution, and the theory of evolution.
Darwin went on a 5 year voyage where he made many new discoveries on plants, animal and their habitats. He discovered that only certain animals live in certain environments.
observations darwin made aboard the beagle
- species vary around the world
- species vary locally
- species vary over time
Fossils: preserved remains of ancient organisms.
Darwin noticed that some extinct animals had many common traits like their ancestors did.
Darwin determined that the DNA structure for each animal is determined by what specie the animal is.
Vestigial structures: structure that's reduced and has little or no function.
Homologous structures: structures that are similar in different species of common ancestry.
Analogous structures: structures that're similar in function but not structure; they don't suggest common ancestry.
The species traits or genetic material have to fit into the environment.
Disruptive Selection: natural selection in which individuals at the upper and lower ends of the curve have higher fitness that individuals near the middle of the curves.
Stabilizing Selection: form of natural selection in when individuals hear the center of a distribution on the curve have higher fitness than individuals at either end of the curve.
Directional Structure: have higher fitness that an individual in the middle or at the other end of the curve.
According to Darwin, differences in adaptations affect an individual's fitness. Individuals with adaptations that are well suited to their environment can survive and reproduce and are said to have high fitness, individuals with characteristics that aren't suited to their environment either die or have few offspring and have low fitness. This difference in rates of survival and reproduction is called survival of the fittest.
-Patterns in the distribution of living and fossil species tell us how modern organisms evolved from their ancestors.
-Many recently discovered fossils form series that trace the evolution of modern species from extinct ancestors.
-Similar patterns of embryological development provide further evidence that organisms have descended from a common ancestor.
-Similar patterns of embryological development provide further evidence that organisms have descended from a common ancestor.
-Evolutionary theory explains the existence of homologous structures adapted to different purposes as the result of descent with modification from a common ancestor.
Hutton: proposes that slow-acting geological forces shape the planet. He estimates Earth to be millions of years old.
Lyell: explains that over long periods, the same processes affecting Earth today have shaped Earth's ancient geological features.
Malthus: Predicts that human population will grow beyond the space and food needed to sustain it.
Lamarck: inheritance of acquired traits.
