Download Earth Science 11 Unit 1 – Geologic Time and Fossils Day 3 notes

Earth Science 11
Unit 1 – Geologic Time and Fossils
Day 3 notes
INTRO TO EVOLUTION:
A look at the History:
 “Uniformitarianism is the assumption that the same natural laws and processes that
operate in the universe now have always operated in the universe in the past and apply
everywhere in the universe”

Formulated by British naturalists in the late 18th century, starting with Scottish geologist
James Hutton and popularized by Charles Lyell’s Principles of Geology in 1830.

Charles Darwin was born on February 12, 1809 in Shrewsbury, England.
 From 1831 to 1836 Darwin served as naturalist aboard the H.M.S. Beagle on a
British science expedition around the world. They came to the Galapagos Islands
and he observed some variation in related or similar species of plants and
animals.
 He formulated that species were different in shapes and sizes due to a process
called Natural Selection.
 Darwin came up with his theory of natural selection from what he observed with
a population of Finches.
 The HIV virus is another current example of natural selection.
Natural Selection key points:
1. Variation exists among individuals in a species.
2. Individuals will compete for resources (food, mates, and space)
3. Competition would lead to the death of some individuals while others would survive
4. Individuals that had advantageous variations are more likely to survive and
reproduce.
Favorable variations are also known as adaptations. An example is the Blob population.
Notes on the Blob story:
Matty 2014
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Earth Science 11
Unit 1 – Geologic Time and Fossils
Day 3 notes
Evidence that supports the Evolution theory:
 Fossil Evidence
• Shows numbers of extinct animals
• Shows similarities between extinct animals and animals that are alive today
• The earth’s layers show a time scale of species and when they appeared on earth
(and when they died out)
 Homologous structures
• these are parts of the body that are similar, but have different functions
 Vestigial Organs
• these are organs or parts that seem to have no function
 Biochemistry and DNA
• When comparing the DNA of one species to another, more similarities are
found in species that are more closely related.
 Embryological Development
• Embryos of different species develop similarly

Direct Observations involving species adaptations:
• Examples:
• Bacteria becoming resistant to drugs
• Dog breeding producing a large variety of dog kinds
• Sexual selection in which mates are selected by beauty, song, strength,
health, etc.
HW: Research Assignment 1.3
Matty 2014
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