Transcript Warm Up: Feb 27th • What do you know about evolution? Give any specific examples of anything you know about it.

Warm Up: Feb 27th
• What do you know about evolution? Give
any specific examples of anything you
know about it.
Warm Up: Feb. 28th
• Who was Charles Darwin? What is he
known for?
Warm Up: Feb. 29th
• Why is the size of a beak important?
Warm Up: March 1st
• What is significant about the Galapagos
Islands?
Today in Science ! ! !
 Begin Evolution
 Standards please
S7L5 Students will examine the evolution of living
organisms through inherited characteristics that
promote survival of organisms and the survival of
successive generations of their offspring.
S7L5.a Explain how physical characteristics of organisms
have changed over successive generations (e.g.
Darwin’s finches and the peppered moths of
Manchester).
S7L5.b Describe ways in which species on earth have
evolved due to natural selection.
S7L5.c Explain how the fossil record found in sedimentary
rock provides evidence for the long history of changing
life forms.
Meet Darwin
Evidence for Evolution
1. In 1831 Charles Darwin traveled around
the world. In the Galapagos Islands he
observed a great variety of organisms like
finches p.175, tortoises and iguanas.
Who was Charles Darwin?
• Darwin had begun to think that species could evolve over time. It
became clear to Darwin that Earth was much older than anyone had
imagined.
• What Is a Species? A species is a group of organisms that can
mate with one another to produce fertile offspring. A characteristic
that helps an organism survive and reproduce in its environment is
called an adaptation.
2. The evidence Darwin collected led him to
theorize that living things change over time
or evolve.
3. Current evidence for evolution: (6) and (5)
A. Fossil record. Oldest fossils buried deeper.
Horses evolved from a dog sized animal 60 mya
B. Phylogeny – the evolutionary history
tells which species evolved from
other species or had common
ancestors.
4. How do we know the phylogeny –
the history of how different organisms
evolved?
Phylogeny is determined . . .
a.
b.
c.
d.
Similar body structures p. 172 G 168`
Similar embryonic development Glencoe 169
Similar DNA codes
Vestigial structures
a. Similar Body Structures
b. Embryonic Development
Because so many species
are so similar in their
development, it may
suggest a common
ancestor.
c. Similar DNA
d. Vestigial structures
Some species have structures that they do
not need. For example,
humans ~ appendix
whales ~ tiny hip bones that whales do
not need may have been inherited
from their walking ancestors.
5. What is Natural Selection? Evolution
occurs because of Natural Selection –
organism that is better adapted lives longer
and produces more offspring.
Natural Selection is the mechanism
behind evolution.
Another way to say it . . .
• Natural Selection ~ the critters that are
better equipped for survival have a better
chance of…(you tell me)?
• That’s pretty straight forward isn’t it?
I mean, imagine you’re in a soup
eating contest (just do it ok!). You
have a fork and your buddy has a
spoon…you ain’t gonna win that
contest.
• Natural selection works in the
same way, only the winner lives,
and the loser…well…I don’t
wanna talk about it.
Natural Selection
•
Big Five Facts ~
1. Overproduction: This refers to the way
many species produce waaaay more
offspring than can possibly survive.
Video clip 12:45
What type of reproduction?
What is that called when the baby looks so different from
the mom? Process of change?
2. Variation (differences) exist
among individuals in a species
3. Competition ~ individuals of a
species compete for resources.
4. Selection : Individuals with
advantageous variations are more
likely to survive.
And those individuals that survive
reproduce and pass on those
advantages through their genes.
When that organism dies the less
advantageous genes die with it
The variations can be a result of
heredity or mutations
Darwin…did he act alone?
• Well…he did but there was another
dude acting alone at the same
time…Alfred Russel (don’t call me
Russell) Wallace.
• Wallace was an admirer of Darwin and
texted him to say that he figured out
the whole natural selection thing.
• And then Darwin was all like…oh no
you didn’t 
• Yes…he did!
This slide from Hightower
Venn Diagram
• Video clip 15 min natural selection
• Compare natural selection to selective
breeding (aka artificial selection)
Evidence
of Species that have evolved
• Bacteria
• Moths
• Finches
Ecology Review
• ..\CRCT\Ecology Review.ppt
Holt Review Games
• Genetics..\..\..\McDougal and review
game\Review Game\rg_L_4 genetics.html
•
..\..\..\McDougal and review game\Review Game\rg_L_5 genetics.html
•
Evolution ..\..\..\McDougal and review game\Review Game\rg_L_6 evolutio.html
Brain Pop
• http://www.brainpop.com/