Transcript Evolution - RHSChemistry

Evolution = a change over time
Evolution of Dance
In order for evolution to occur variation (changes) in
genes such as mutations, must exist
Organism’s genes change because of mutations—which
can be helpful, harmful, or have no effect.
Charles Darwin
Scientist that is credited with proposing the
theory of evolution by the process of
natural selection
Darwin wrote a book on Evolution called On the Origin of Species
He traveled to the Galapagos Islands aboard
the Beagle where he formed many of his ideas
on Evolution
Natural Selection
Organisms better suited to their
environment survive, reproduce and pass on
their genes better than organisms not well
suited to their environment
Natural Selection results in a change in gene frequency
Examples—Jellyfish Lake and PepperedMoths
http://www.youtube.com/watch?v=DhpaqFya2pg
http://www.youtube.com/watch?v=LyRA807djLc
Kettlewell’s famous experiments with the peppered
moth illustrated how organisms adapt to their
environment by the process of natural selection.
He observed that there were more dark moths than
light moths in regions where soot covered the trunks
of trees.
there were Also more light moths than dark moths
in regions where the tree trunks were light in color
and not soot covered.
Adaptation
An inherited characteristic that improves an
organism’s ability to survive and reproduce in a
particular environment
• Examples
– Finch beaks
– Birds of Paradise mating rituals
http://www.youtube.com/watch?v=SB8UodV_DJg
Leaves
Fruit & Nuts
Seeds
Insects
Uses a twig to dig insects out of tree bark
Grubs
Adaptation Artistry
• Create a new and improved organism that is
better suited to its environment. Draw a
picture of your new organism and fit it with
3 NEW ADAPTATIONS. Describe how
each of these adaptations allow it to be
better suited to its environment
Evolution Notes....Part 2
Let’s Review
Peppered Moth Simulation http://www.techapps.net/interactives/pepperMoths.swf
Evolution = a change over time We focus on a change in GENES
Natural Selection Organisms better suited to their
environment survive, reproduce and pass on their genes better
than organisms not well suited to their environment
Adaptation An inherited characteristic that improves an
organism’s ability to survive and reproduce in a particular
environment
Microevolution
1. Changes occur within a species
2. Occur over a shorter amount of time
3. More easily observed
Examples
Weed resistance to herbicides
Insects resistance to pesticides
Bacteria becoming immune to antibiotics-superbugs!
Macroevolution
1. Describes the formation of an entirely new species
from an existing species
2. Difficult to observe since it happens over a long period
of time—millions of years
Example
theory
Ape to man
Evidence used for Evolution:
1. Fossils – oldest evidence
2. Homologous Structures
Structures that may show common ancestry because they look similar
Whale
Bat
Human
Cat
3. Vestigial Structures
Structures that organisms have, but do not need or
use
Example
Whales have a Pelvic Bone
Modern
4. DNA and Amino Acids
• Determine the number of differences for
each organism compared to humans