Theory of Evolution by
Natural Selection
1. Put the following pictures in the correct
sequence (order) from oldest to most recent.
A
E
C
B
D
SWBAT identify the four parts of natural
selection. (8.3.8)
1. How are the following 4 organisms
equipped to survive in their environments?
2. How might a long tongue help a
butterfly survive in its environment?
Evolution – the theory in which populations
gradually change over time
Natural Selection Trailer
Darwin observed that all of the birds he
collected in the Galapagos Island were all
finches!
They were different from each other because
they had different shaped beaks.
Natural Selection - the process by which
organisms that inherit advantageous traits
tend to reproduce more successfully than
other organisms do.
Overproduction - an animal has more
offspring than will survive
Example: Not all Jaguar cubs will survive to
reproduce.
Genetic Variation- differences exist within
a species that might give that organism an
advantage to survive
Example: Jaw size of the Jaguar
Selection – the organisms that are able to
get the resources they need are more likely
to survive
Example: The variation in jaw size allowed
the Jaguar to eat different prey when their
normal prey became hard to find.
Adaptation – an inherited characteristic
that helps an organism survive and
reproduce in its environment
Example: Eventually the larger jaw
became more common in the Jaguar.
Examine the images on pages 406-407.
Complete the table for question #15 on
page 407.
Extinction – death of every member of a
species
Which type of natural selection do you
think best fits the picture below? Explain
why you think so.
6-1 Lesson Review, page 409