Alfred Russell Wallace
Independently reached the same conclusion as Darwin about evolution (natural selection). Like Darwin, he looked at groups of animals and found them to be closely related yet different.
A mechanism for descent with modification - a natural process that results in the evolution of those organisms best adapted to the environment. Darwin based this idea on four things: (1) overproduction (more offspring are produced than survive); genetic variation (individuals within a population have different traits); (3) struggle to survive (also called adaptation); and (4) differential reproduction (those with the best adaptations are more likely to survive and reproduce).
The development of new types of organisms from pre-existing types of organisms over time.
Rock layers formed as new layers of rock are deposited over time.
A trait that makes an individual or population well-adapted to survive in its environment (e.g., thick fur keeps an animal warm).
The ability of an individual to survive and reproduce in its environment; and the measure of hereditary contributions to the next generation.
Survival of the Fittest
A natural process resulting in the evolution of organisms best adapted to the environment.
Ideas of Evolution
Charles Darwin noticed that the animals on Galapagos Island were similar but varied from one island to another. He was concerned that they changed over time but did not know why.
English natural scientist (1809-1882) who formulated the theory of evolution by natural selection. He wrote in his book ON THE ORIGIN OF SPECIES, in 1859, that evolution could be explained by "natural selection."
A biologist who studies botany and zoology.
A well-supported explanation for some aspect of the natural world.
A person with advanced knowledge of one of more sciences.
A science that deals with the history of the earth as recorded in rocks.
A paleontologist who studied fossils in strata and found evidence that organisms in the past were different from current species and are now extinct. He came up with the theory of "catastrophism" to explain his finding.
A sudden geologic catastrophe (e.g., an earthquake) caused the extinction of large groups.
Charles Lyell's idea that geologic processes have not changed throughout Earth's history, which means the geologic processes that operate today also operated in the past.
The "Father of Modern Biology" believed in "Uniformitarianism" (all geologic processes occur now at the same rate that they always have occurred).
Jean Baptiste de Lamarck
French naturalist who came up with the idea of "Inheritance of Acquired Characteristics" (i.e., simple organisms can arise from non-living matter and develop into more complex forms). Other scientists did not buy this theory.
Inheritance of Acquired Characteristics
Lamarck's theory that physical changes in an organism would be passed on (e.g., if a giraffe stretches its neck to reach food then its offspring will have longer necks).
ON THE ORIGIN OF SPECIES
The name of Darwin's, book published in 1859, which presented evidence and proposed a mechanism for evolution (i.e., "natural selecion").
Descent with Modification
Darwin's idea that all species living on earth today descended from earlier species.
Adaptation in a single organism in response to changes in environmental conditions, like a new climate, altitude or environment.
The remains (or an impression) of a plant or animal that existed in a past geological age and that has been excavated from the soil.
The placement of one thing on top of another.
The age of something compared with other things. For example, the age of a rock compared with other rock layers.
The calculated age of an artifact from a specific dating method that is used to determine when the artifact was made.
The geographical distribution of animals and plants.
Having the same evolutionary origin but serving different functions (e.g., the wing of a bat and the arm of Andrew).
How something is constructed and the arrangement of its parts.
Structures with similar functions but different evolutionary origins.
When two or more species NOT descended from a common ancestor develop similar traits
In biology, the sequence of events involved in the evolutionary development of a species.
Age of Fossils
The oldest fossils are in the oldest rock layers which are at the bottom. Younger fossils are found in later upper rock layers.
The scientist who noticed that rocks tend to lie in horizontal layers, with the youngest layers at the top.
Geologic Time Scale
A time line that allows scientists to identify the relative age of a fossil.
Using a radioactive process to determine the age of an item.
Distribution of Fossils
Different organisms lived at different times. Today's organisms different from those in the past. Fossils adjacent to each other are more like each other than those that are far apart. We can infer when and where different organisms existed by comparing fossils and rocks from around the planet. Species have differed in a gardual sequence of forms over time.
The scientific study of the structure of animals that is also called morphology.
The branch of biology that studies the formation and early development of living organisms.
The process by which two species evolve in response to changes in each other.
Structures that evolved independently.
Structures once necessary in ancestral forms, but no longer needed today.
The chemical compounds that provide physical structure and that bring about movement, energy use, and other cellular functions.
A comprehensive theory of evolution that incorporates genetics and includes most of Darwin's ideas, focusing on populations as the fundamental units of evolution.
When two or more species sharing a common ancestor become more different over time.
An evolutionary pattern in which many species evolve from a single ancestral species.
The selective breeding of domesticated plants and animals to encourage the occurrence of desirable traits.