Lesson 2 Flashcards
Darwin hypothesized that species can change as a response to
their environment and habitat
Darwin proposed that evolution occurs due to the effects of
natural selection
James Hutton proposed a theory of
slow, uniform geological change
Charles Lyell: Uniformitarianism
The natural processes that take place are the same now as they always have been
Thomas Malthus: Essay on the Principle of Population
the size of human populations is limited only by the
quantity of resources
Biogeography
the study of geographical
distribution of organisms throughout the world
Evolution
The change in
inheritable traits
of a species over
many generations
Species
A group of organisms that can
reproduce and create offspring
that can also reproduce
Microevolution
small scale, effects a singular population
Macroevolution
Large scale, affects changes in species across populations
Natural selection
descent with modification
environmental factors directly impact:
the ability for organisms to survive, causes them to change phenotype over time
Biological Fitness
The ability to survive,
reproduce, and produce viable offspring
4 main principles of Darwin’s findings
- Organisms exhibit variations that can be passed
from one generation to the next. - Organisms compete for available resources.
- Individuals within a population differ in terms
of their reproductive success. - Organisms adapt to conditions as the
environment changes
Variation
Organisms exhibit variations that can be passed
from one generation to the next
How does variation happen in a
population?
DNA mutations
Differences in phenotype may influence
an organism’s ability to find, obtain, or utilize its
RESOURCES (food, water, shelter, oxygen, etc.)
* the organism’s ABILITY TO REPRODUCE
Organisms with phenotypes that don’t interact well with the
environment are more likely to die and less likely to reproduce
Natural Selection
The process by which
random evolutionary
changes are
selected for by nature in a
consistent, orderly, non-
random way.
Homologous structures
similar in structure / different in function
* evidence of a common ancestor
Analogous structures
have a SIMILAR FUNCTION
* evolved separately
* NOT evidence of common
ancestor
Vestigial structures
remnants of organs or structures that
had a function in an early ancestor.
Ex. Ostrich wings
Biochemistry provides evidence for evolution:
All living things contain DNA and proteins - common ancestry
sequence of amino acids
