Download Evolution * Natural Selection

Evolution:
Natural Selection
Evolution
• Change in inherited characteristics over time.
(Descent with modification)
Before the 1800’s few thought much about
evolution
1. Most people thought the earth was only 6,000 years old (not 4.6
billion years old)
2. Few traveled to see similarities in species
3. Many people (of European descent) understood only
the biblical story of creation.
http://mythicjourneys.org/bigmyth/
In the 1800’s scientists started to change people’s
minds….
Lamarck
• A French scientist who proposed that traits developed during a
parent’s life would be passed onto their kids.
Example: giraffes
stretch their neck to
reach tall leaves, this
results in a long neck.
This trait is then
inherited by the kids.
Lamarck didn’t realize not all things are passed
onto the offspring
=
Plastic Surgery does NOT get passed onto your
offspring!
Before surgery
After surgery
Genetics wasn’t described until the 1860’s by
Mendel
Charles Darwin
• A British scientist who studied nature and noticed similarities among
animals.
• He concluded that
living things must be
related and somehow
they changed, or
evolved, over time
due to natural
selection.
Natural Selection
• An organism with the best traits for their environment is more likely
to survive and reproduce
Which mouse is
better suited for
this
environment?
Survival of the Fittest
• Which moth has the
best traits for this
environment?
• What will happen to
the “unfit” moth?