Download Chapter 7-3 Cornell Notes

7th Chapter 7-3 Cornell Notes
“Evolution of
Species”
7th Chapter 7-3 Cornell Notes
1. How do new
species form?
Key Questions
2. What causes the
extinction of species?
Chapter 7-3 Cornell Notes: Terms
habitat
extinct
Chapter 7-3 Cornell Notes Paragraph 1
different environments + genetic variation +
natural selection = variety of organisms;
natural selection created
organisms adapted to
their habitats;
habitat: specific environment
gives what organisms need to
live/grow/reproduce.
Chapter 7-3 Cornell Notes
Paragraph 2
traits vary between organisms in a species;
causes: DNA mutation, genes
shifting during meiosis;
total gene pool:
sum of genetic
variations in a
species;
the more variation in a species = the
better chance of surviving
environmental change.
Chapter 7-3 Cornell Notes
Paragraph 3
new species can form through geographic
isolation (i.e. Kaibab squirrel);
new species then cannot mate with
the old species successfully.
Chapter 7-3 Cornell Notes
evolutionary relationships:
1.
DNA evidence (nitrogen base sequences)
2.
protein structure
3.
fossils
4.
early development (embryos gill slits)
5.
body structure (homologous bones) ;
Paragraph 4
Chapter 7-3 Cornell Notes
Paragraph 5
extinct: no members of the
species still alive;
cause: change in
environment;
needs adaptation to
survive changes ( to
survive and reproduce);
climate change may destroy habitats but
adaptations can help survival.