Unit 4: Evolution
Lesson #
10.3: Natural and Artificial Selection
Work on the Journal on the Board
Time for a Refresher
• How old is the Earth?
• How do you define “species”?
• What is the unifying concept in biology that
provides an explanation for the vast diversity
of life?
Agenda
• Journal
• Notes
• Video: Note-taker and Exit Quiz is due today
• Homework: Study everything so far for a quiz
• Quiz next class! No notes!
Objectives
• Describe the process of natural
selection
• Provide one example of artificial
selection
But first, let’s talk about flowers and bugs…
• What kind of
flower is this?
But first, let’s talk about flowers and bugs…
• Hi there! I am a cute
praying mantis!
• Why would looking
like this be helpful?
But first, let’s talk about flowers and bugs…
• Would you hold me?
• What is selecting for
these traits?
But first, let’s talk about flowers and bugs…
• How about
holding me?
But first, let’s talk about bugs…
• How about holding me?
• Why might organisms in the same
species look so different?
But first, let’s talk about bugs…
• Do I look scary?
• Why might this
appearance be helpful?
This class is going to the dogs…
• What forces selected for
these traits?
• Why might organisms in
the same species look so
different?
Natural & Artificial Selection
• When humans change a species by
breeding it for certain traits is called
artificial selection.
• This process has shaped our food and
our pets!
• In order to shape a species, the trait
we select for must be heritable.
• Heritability is the ability of a
trait to be passed down from one
generation to the next.
• What are some traits that are
heritable?
• Natural Selection: The survival and
reproduction of the organisms that
are genetically best adapted to an
environment.
• In natural selection, the selective
agent is the environment. (video)
• FITNESS: The combination of
physical traits and behaviors that
help organisms survive and
reproduce
• Describe how this insect’s camouflage
improves it fitness…
• Is a super buff insect more “fit” than
a really well camouflaged insect?
• Natural Selection is the Result of:
• Mutations in DNA that
produce variations within a
population
• These variations result in some
organisms being more “fit”
than others
• Natural Selection is the Result of:
• The organisms that are the most “fit”
are able to pass on their superior traits
to the next generation
• This can also be described as decent
with modification
VIDEO TIME!
Fill out your note-taker for the video. It will be
collected for points.
Video Link
Activities
• Vocabulary flipbook
• Create your flipbook
• Get a vocabulary sheet
• Use the book to write the definition
• You MUST draw a picture for each word
• This is due next class