Evolution

mutation

any change in the DNA sequence of a cell. Can be harmful, beneficial, or have no effect.

evolution

change in species over time

Jean Baptiste Lamark 1809

was one of the first scientists to propose that species evolve by natural selection. States that trats an organism develops during its own lifetime can be passed on to offspring

natural selection (1859)

an organism's relative ability to survive and produce fertile offspring

James Hutton (1785)

was one of the first to say that Earth must be far older than most people believed

Charles Lyell (1833)

argued that gradual geological processes have gradually shaped Earth's surface

Thomas Malthus (1798)

argued that human populations grow faster than the resources they depend on

Galapagos Islands

small volcanic islands where Darwin made many important observations

Alfred Russel Wallace (1858)

developed a theory of evolution at the same time as Darwin

HMS Beagle

ship on which Darwin served as naturalist

vestigial structures

reduced structures that are no longer used

Charles Darwin (1859)

developed the theory of evolution by natural selection

5 years

the voyage of the Beagle circled the globe. This voyage lasted...

Natural selection states that...

- a change in a species occurs over time
- fitness is an organism's ability to survive and produce fertile offspring
- nature selects the variations within a species that are most useful for survival

artificial selection states that...

- a rapid process
- produces organisms with selected traits
- the breeder chooses what traits to be inherited
- does not facilitate evolution

analogous structures

same function, different structure

homologous structures

different function, same structure
structures that are similar in related organisms because they were inherited from a common ancestor

example of analogous structure

the wings of bats and birds, since they're genetically related and have different ancestors

example of homologous structure

the limbs of humans and apes

example of vestigial structure

human tail bone