Transcript Welcome to Science 3/1

Welcome to Science 3/1
• Answer the following question on your piece of
paper: There are nearly 2 million individual species
of organisms on Earth. Each species is extremely
unique. In your opinion, explain how these species
came to be here on Earth.
• Today’s Schedule
• 1. Pass Back and Review Test
• 2. Darwin’s Voyage
• 3. Assignment
High Test Scores!!!!!!!!!!!!!!!!!
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3rd- Luke, Emma, & Mark 27/28
5th- Lindsey 28/28
7th- Alex & Megan S. 28/28
8th- Jacob 28/28
9th- Brennan, Noah, & Dan 25/28
• Great Job
How did all living things that have ever
lived on Earth get here?
• The scientific answer would be evolution.
• Evolution is technically defined as: "a gradual
process in which something changes into a different
and usually more complex or better form."
• Some finches have wide beaks to break open and
eat seeds.
• Some finches have pointed, sharp beaks to eat
insects.
Charles Darwin
• At 22 years old. He traveled the world to learn as
much about living things as he could.
• He saw tremendous diversity (variety) in the living
things he saw.
• Today, scientists have identified 1.7 million
different species (similar organisms that can mate
& reproduce)
• Darwin’s Voyage
Similarities & Differences
Darwin noticed many
similarities & differences
between the animals he saw.
Iguanas- on the islands they had
large claws. On land short claws.
Cormorants- on the islands they
could not fly. On land they could
Darwin inferred that a small
number of plants and animals
had come to the islands from
the mainland.
Adaptations
• Darwin concluded
that over time, the
organisms that were
isolated on the islands
began to adapt to life
on the islands. (They
developed traits that
helped them survive
and reproduce.)
Evolution
• After his journey, Darwin spent the next 20 years
researching his findings.
• Darwin concluded that the organisms that arrived on the
islands faced conditions that were different than those on
the mainland.
• Darwin thought the species gradually changed
over time to adapt to the new conditions.
(Evolution)
What causes organisms to change?
• Natural Selection- Survival of the Fittest
• Individuals better suited to the environment are
more likely to survive and reproduce than other
members of the same species.
• Untamed and Uncut:Video : Animal Planet
How does Natural Selection Work?
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Video -- Baby Sea Turtles Attacked -- National Geographic
• Species must produce more offspring than can possibly
survive.
• Why?
• Life in the wild is hard. Your whole life revolves around
finding food and trying to avoid becoming food.
• If a species does not reproduce enough offspring it will
slowly become extinct.
How does Natural Selection Work?
• Offspring must compete with each other to
survive.
• Some turtles will find food better than others.
• Some turtles will escape predators better than
others.
• The turtles that can survive will get to reproduce.
How does Natural Selection Work?
• Some baby turtles will be able to swim or move
faster than others.
• Some baby turtles will have better camouflage than
others.
• These are variations, or differences between
individual members of a species.
Conclusion
• Organisms have variations that make them
different.
• Over time, nature will “select” the organisms with
beneficial variations to survive and reproduce.
• Over a long, long, time natural selection can lead to
evolution. Helpful variations, gradually accumulate
in a species, while unfavorable ones disappear.
Assignment
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Write down and define the following terms:
Species
Answer Questions
Adaptations
1-4 on page 150.
Evolution
Natural selection
Overproduction
Competition
variations
Animal Variation Bonus Assignment
• All organisms have variations that help them
survive.
• You are going to create a Super Animal by
combining the best variations from a variety of
characters.
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Blue Jay v. Moths
Natural Selection Simulation
Peppered Moth Simulation (Paper & Pencil)
Evolution Crossword (2)