EvolutionNatural Selection - PowerPoint PPT Presentation

Title: EvolutionNatural Selection


1
Evolution/Natural Selection

• Individual organisms differ and some variation
  can be inherited (fitness).
• Fitness is the ability of an organism to survive
  and reproduce.
• Organisms produce more offspring than can
  survive.
• Compete for limited resources.
• Survival of the Fittest
• Organisms that survive pass their traits on to
  the next generation.

2
Evolution

• Over time natural selection results in changes in
  the inherited characteristics of a population.

3
Click on the link below to play the video.
Natural_Selection__Adaptations__and_Environmental_
Changes.asf
4
http//www.explorelearning.com/Gizmo lab Natural
Selection
You may use another version of a Peppered Moth
Lab.
5
SPECIATION

• Natural selection and chance events can change
  the relative frequencies of alleles in a
  population and result in the formation of a new
  species.

6
DIVERSITY

• Natural Selection leads to a wide variety of
  species.
• Darwin observed that the characteristics of many
  animals and plants varied noticeably among the
  different islands of the Galapágos.
• Galapágos island Finches are a good example of
  diversity.

7
PHYLOGENY

• The study of evolutionary relationships among
  organisms.
• Biologists now group organisms into categories
  that represent lines of evolutionary descent.

8
ADAPTATION

• Inherited characteristic that increases an
  organisms chance of survival.
• Survival of the fittest.

9
Behavior

• The way an organism reacts to changes in its
  internal condition or external environment.

10
EXTINCTION

• The disappearance of a species from all parts of
  its geographical range.
• Example Dinosaurs

11
Questions on Natural Selection/Evolution
1.The competition between members of a species
for basic needs such as food and living space is
called A.     Survival of the fittest B.    
Fitness C.     Adaptation D.     Variation
12
2. An inherited characteristic that increases an
organism's chance of survival is known as a
(an) F.      Adaptation G.     Dominant
trait H.     Vestigial organ J.       Evolution
13
3. The ability of an organism to survive and
reproduce in its environment is called A.    
Artificial Selection B.     Natural
Selection C.    Selective Use D.     Fitness
14
4. Which of the following is NOT part of Darwins
theory of evolution? F. Struggle for existence G.
Inheritance of acquired characteristics H.
Descent with modification J. Survival of the
fittest
15

• 5. Fitness is a result of
• Adaptations
• Homologies
• Common descent
• Variation