Unit 7: Evolution

A change in the genes over time
Inherited characteristic of a species that develops over time in response to an environmental factor, enabling the species to survive.
Punctuated Equilibrium
Populations stay stable for long periods of time, interrupted by brief periods of rapid change. Caused by environmental change or increased mutation rate. Supported by fossil record.
Charles Darwin
Father of evolution. Developed the theory of natural selection.
Survival of the Fittest
The mechanism of natural selection. Individuals that are better equipped for their environment are more likely to survive and pass on their traits to offspring.
Plate Tectonics
The theory that Earth's outer shell is divided into several plates that glide over the mantle, the rocky inner layer above the core.
The Beagle
The ship that Charles Darwin traveled to the Galapagos Islands on.
Artificial Selection
The process by which humans breed other animals and plants for particular traits.
Small genetic changes occur slowly within a population.
Darwin's original description of evolution.
Fossil Record
Fossils and the order in which they appear in layers of sedimentary rock.
Natural Selection
The process whereby organisms better adapted to their environment tend to survive and produce more offspring.
A group of organisms living in the same habitat that belong to the same species.
A group of living organisms consisting of similar individuals capable of breeding.
A permanent change of the nucleotide sequence of DNA
Divergent Evolution
Accumulation of differences between different populations which can lead to the formation of new species.
Vestigial Structure
genetically determined structures or attributes that have apparently lost most or all of their ancestral function in a given species, but have been retained through evolution.
Analogous Structure
Structures with similar function but not common structure or common ancestor.
Different or distinct form or versions within a species.
The evolution of two species that are totally dependent on each other.
a contest between organisms for territory, a niche, or a location of resources, for resources and goods, mates, for prestige, recognition, awards, or group or social status, for leadership needed for survival.
Gene Pool
The total collection of genes in a population at any one time.
Main Points of Natural Selection
1. There is variation within a population
2. Some variations are favorable
3. Not all young produced in each generation can survive
4. Individuals that survive and reproduce are those with favorable variations
The place where a population lives.
Homologous structures
Structures that are similar because of common ancestry but not necessarily common function.
a tree diagram used to illustrate evolutionary relationships between species.
is the evolutionary process by which new biological species arise.
The study of the form and structure of organisms.
Convergent evolution
independent evolution of similar features in species of different ancestors.

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