Transcript Learning Target: I can describe Charles Darwin’s observations and explain the theory of evolution  I can identify whether adaptations are behavioral or structural and.

Learning Target:
I can describe Charles Darwin’s
observations and explain the theory of
evolution
 I can identify whether adaptations are
behavioral or structural and explain how
they help an organism survive in its
environment

EVOLUTION
NOTES Part 1
Evolution = Change in species over time
 All life has a common (shared) ancestor and
ALL species change

Species = Distinct group of organisms
that can interbreed (have babies) –
physical, behavioral, & molecular
similarities
*Theory = Best explanation based on much
evidence
*Continuous (organisms keep changing,
depending on needs in environment

I. History of Evolution
A. Charles Darwin (1809-1882)
1. Sailed around the world on the
HMS Beagle, 1831-1836
2. Naturalist – carefully observed living things

3. Most important visit: Galapagos Islands:
Group of small islands west of South
America with unique environments
B. Darwin’s Observations
1. Organisms on each island were unique and adapted to
their environments
a. Adaptation = Trait that helps an organism to survive
in its environment
Types of Adaptations:
i) Behavioral: Things organisms DO
Ex: Migrating; Being nocturnal; hibernating

ii) Structural: Physical characteristics
Ex: Defensive structures (thorns, teeth)
Color/camouflage
2. Darwin’s Finches – small birds on each island
a. Had a common ancestor – finches from the
mainland
b. Beak shape changed according to food type
3. The Origin of Species
a. Darwin’s book published in
1856
b. Described his theory that all
organisms are constantly
changing in response to their
environment
Video Assignment
 Use
your notes and details from the videos
to write a 1-2 paragraph essay on this
topic:
 How did Charles Darwin’s study of birds
help him develop his theory of evolution?
What is evolution, and why does it happen?
How do we know it happens? What does it
tell us about all life on earth?
 Due 4/10 (Weds)
Video 1:
http://www.youtube.com/watch?v=GhHOjC
4oxh8
 Video 2:
 http://www.youtube.com/watch?v=l25MBq
8T77w

LEARNING TARGET

I can explain how the fossil record,
anatomy, and other evidence support the
theory of evolution
Notes continued…

Halfway down page 2
II. Evidence for Evolution
A. Comparative Anatomy (Body structure)
1. Homologous Structures – body parts that
have different functions but developed from
similar body parts
Ex) Human arm bone / Bat wing / whale
flipper
2. Vestigial organs – parts that
have lost their function
Ex) Human appendix – other
animals need it for digestion
Leg bones in snake
Pelvis in whales
B. Similarities in Development
1. Embryo – organism in very early stages
of development
2. Early embryos of most species are almost
identical (tail, gill slits, etc.)
C. Fossils – Evidence of dead
organisms (ex. bones, shells) that
are hardened and preserved
1. Intermediate/ “in-between” fossils show
that different species are related
Ex) Archaeopteryx – small dinosaur
with feathers
Ex) Tiktaalik – “fish with legs”
2. Fossils of current animals show change
over time
Ex: Horses used to be smaller with
separated toes
Ex: Humans had ancestors
that were similar to apes
D. Similarities in chemical compounds
1. All organisms share same basic chemicals:
*DNA, carbon, hydrogen, oxygen, amino acids
2. Comparison shows relationships of organisms
Ex: Dog & wolf DNA is 98.8% similar!
And now…

Close & Critical Reading about a real
discovery about Evolution from a few years
ago!

Please answer the survey questions at the
beginning and end

*Due tomorrow 4/11!