Chapters 16 & 17
Evolution of Populations and
The History of Life
Evolution of Populations
• EQ: How can populations evolve to form
new species?
– How do genes make evolution possible?
– W...
Background and Review:
How are evolution and
genetics related?
Jean-Baptiste Lamarck
He was the first to propose how organisms
could change over time.
Theory of Acquired Characteristics
• Theory that organisms’ selective use and disuse
of organs led to acquiring or losing ...
Darwin
Proposed the mechanism of NATURAL
SELECTION to explain the observable
patterns of evolution
Darwin
On what concept was this work based?
Observations
• Members of a population often vary greatly in
their triats
• Tr...
Darwin
On what concept was this work based?
Inferences
• Individuals whose inherited traits give
them a higher probability...
Genetics & Evolution
• Scientists discovered that heritable traits
are determined by DNA (genes on
chromosomes).
• Later t...
Evolution acts on ______________________ not on individuals.
Example: Black lizards are able to absorb more heat on cold d...
How do genes make
evolution possible
Two main sources of
genetic variation
1. Mutations—change in genes (DNA
sequence) or chromosomes
2. Gene recombination—mix...
What causes a population’s
gene pool to change?
Gene Pool
The combined genetic information of all the
members of a particular population
Selection processes
Stabilizing-natural selection in which
intermediate phenotypes survive more
successfully than do extre...
Selection processes
Directional- natural selection in which
individuals at one end of the phenotypic
range survive more su...
Selection processes
Disruptive-natural selection in which
individuals on both extremes of a
phenotypic range survive more
...
Selection Curves
How do new species
form?
Species
• A group of similar organisms that can
breed and produce fertile offspring
Genetic Drift
Random change in allele frequencies that
occur in small populations
Speciation
Formation of a new species through
reproductive isolation
Example: Galapagos Island finches and
tortoises
Darwin’s Galapagos Island
finches
Three types of reproductive
isolation
1. Behavioral isolation (sounds or display rituals)
2. Temporal isolation (nocturnal...
Geographical Isolation
Allopatric Speciation
Gr. other + fatherland
The formation of new
species in populations
that are geographically
isolated....
Sympatric Speciation
Gr. together + fatherland
Formation of a
new species in
populations that
live in the same
geographic ...
Behavior
A way an organism reacts to changes in
its internal condition or external
environment
Migration
Periodic movement and return of animals
from one place to another. Organisms that
migrate have an advantage over...
Migration
• Example:
• 1. Monarch Butterfly
• http://video.pbs.org/video/1063682334 (2min)
• 2. Salmon
• To the left:
• Pi...
Courtship
Type of behavior in which an animal sends
out stimuli in order to attract a member of
the opposite sex.
30 Minut...
Social Behavior
The interaction of members with their own
species in a way to increase the fitness of
all members.
Ex: pac...
Chapter 17
The History of Life
EQ: How do fossils help biologists
understand the history of life on Earth:
– How do scientists use fossils to study Earth...
Earth’s Early Atmosphere
• Over time photosynthetic bacteria became
common in the sea which started adding
oxygen to the a...
• The ozone layer started to form to provide
protection from ultraviolet rays
• Some organisms evolved ways of using
oxyge...
Miller and Urey Experiment
Carl Sagan Explains Miller-Urey Experiment:
http://www.youtube.com/watch?v=79o6xzMfzKg

Miller-...
Fossil
• Preserved remains of ancient organisms
• http://www.neok12.com/php/watch.php?
v=zX076e0e6d5a7b775b0d7a41&t=Fossil...
Fossil Record
Information about past life that has been
obtained from fossils
1. Most organisms that have
ever lived are now extinct
2. fossils occur in a particular
order in the rock layer
3. groups ...
Extinct
A species that has completely died out

Extant
Species that still survive
Where do most fossils
form?
Most fossils form in sedimentary
rock as weight compresses layers
of sediment in bodies of wat...
• Not all parts of animals become fossilized.
• Fossilization activity
http://www.ucmp.berkeley.edu/education/e
xplorations/tours/fossil/5to8/Intro.html
What are some patterns
in which evolution has
occurred?
Mass Extinction
Many types of living things become extinct
in a short period of time
Ex: Dinosaurs
Asteroid hitting Earth ...
How fast does
evolution take place?
Gradualism
A model of evolution which theorizes that
most speciation is slow, uniform and
gradual.
Punctuated Equilibrium
Long period in which a species undergoes
little to no change, interrupted by relatively
brief perio...
Catastrophism
The principle that events in the past
occurred suddenly and were caused by
different mechanisms than those
o...
Chapter 16 & 17 Evolution of Populations and The History of Life
Chapter 16 & 17 Evolution of Populations and The History of Life
Chapter 16 & 17 Evolution of Populations and The History of Life
Chapter 16 & 17 Evolution of Populations and The History of Life
Chapter 16 & 17 Evolution of Populations and The History of Life
Chapter 16 & 17 Evolution of Populations and The History of Life
Chapter 16 & 17 Evolution of Populations and The History of Life
Chapter 16 & 17 Evolution of Populations and The History of Life
Upcoming SlideShare
Loading in …5
×

Chapter 16 & 17 Evolution of Populations and The History of Life

1,805 views

Published on

Presentation of Materials that will be covered in this Unit designed to meet the standards of the Quality Core Exam for the state of Kentucky.

Published in: Education, Technology
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total views
1,805
On SlideShare
0
From Embeds
0
Number of Embeds
936
Actions
Shares
0
Downloads
27
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide

Chapter 16 & 17 Evolution of Populations and The History of Life

  1. 1. Chapters 16 & 17 Evolution of Populations and The History of Life
  2. 2. Evolution of Populations • EQ: How can populations evolve to form new species? – How do genes make evolution possible? – What causes a population’s gene pool to change? -- How do new species form?
  3. 3. Background and Review: How are evolution and genetics related?
  4. 4. Jean-Baptiste Lamarck He was the first to propose how organisms could change over time.
  5. 5. Theory of Acquired Characteristics • Theory that organisms’ selective use and disuse of organs led to acquiring or losing certain traits in their lifetime. • These traits could then be passed on to their offspring • Ex) giraffe stretching to get leaves = neck gets longer over time….pass longer neck on to offspring (incorrect)
  6. 6. Darwin Proposed the mechanism of NATURAL SELECTION to explain the observable patterns of evolution
  7. 7. Darwin On what concept was this work based? Observations • Members of a population often vary greatly in their triats • Traits are inherited from parents to offspring • All species are capable of producing more offspring that their environment can support
  8. 8. Darwin On what concept was this work based? Inferences • Individuals whose inherited traits give them a higher probability of surviving and reproducing in a given environment tend to leave more offspring than other individuals • This unequal ability of individuals to survive and reproduce will lead to the accumulation of favorable traits in the population over generations.
  9. 9. Genetics & Evolution • Scientists discovered that heritable traits are determined by DNA (genes on chromosomes). • Later they realized that changes in the DNA (mutations) and gene recombination through sexual reproduction results in variations; thus, further relating Darwin and Mendel’s original work.
  10. 10. Evolution acts on ______________________ not on individuals. Example: Black lizards are able to absorb more heat on cold days. The extra heat allows them to move more quickly on cold days which makes them better able to avoid predators. The allele for black body would increases an individuals fitness and they would leave more offspring that other lizards. The relative frequency of the allele for black body could, therefore increase.
  11. 11. How do genes make evolution possible
  12. 12. Two main sources of genetic variation 1. Mutations—change in genes (DNA sequence) or chromosomes 2. Gene recombination—mixing of genes that result from: A. meiosis B. sexual reproduction
  13. 13. What causes a population’s gene pool to change?
  14. 14. Gene Pool The combined genetic information of all the members of a particular population
  15. 15. Selection processes Stabilizing-natural selection in which intermediate phenotypes survive more successfully than do extreme phenotypes
  16. 16. Selection processes Directional- natural selection in which individuals at one end of the phenotypic range survive more successfully than do other individuals.
  17. 17. Selection processes Disruptive-natural selection in which individuals on both extremes of a phenotypic range survive more successfully than do individuals with intermediate phenotypes
  18. 18. Selection Curves
  19. 19. How do new species form?
  20. 20. Species • A group of similar organisms that can breed and produce fertile offspring
  21. 21. Genetic Drift Random change in allele frequencies that occur in small populations
  22. 22. Speciation Formation of a new species through reproductive isolation Example: Galapagos Island finches and tortoises
  23. 23. Darwin’s Galapagos Island finches
  24. 24. Three types of reproductive isolation 1. Behavioral isolation (sounds or display rituals) 2. Temporal isolation (nocturnal vs. diurnal) 3. Geographical isolation (separated by oceans or mountain ranges) If one of the Earth’s plates moves 1.9 cm a yr., in 1 million years it would move 12 miles
  25. 25. Geographical Isolation
  26. 26. Allopatric Speciation Gr. other + fatherland The formation of new species in populations that are geographically isolated. Ex: mountains, canyons, or oceans
  27. 27. Sympatric Speciation Gr. together + fatherland Formation of a new species in populations that live in the same geographic area.
  28. 28. Behavior A way an organism reacts to changes in its internal condition or external environment
  29. 29. Migration Periodic movement and return of animals from one place to another. Organisms that migrate have an advantage over one’s that do not.
  30. 30. Migration • Example: • 1. Monarch Butterfly • http://video.pbs.org/video/1063682334 (2min) • 2. Salmon • To the left: • Pink • salmon • moving • upstream.
  31. 31. Courtship Type of behavior in which an animal sends out stimuli in order to attract a member of the opposite sex. 30 Minute Mark: http://www.pbs.org/wnet/nature/episodes/what-males-will-do/video-fullepisode/5374/ http://www.pbs.org/wnet/nature/video/what-males-will-do-video-spidercourtship-dance/956/
  32. 32. Social Behavior The interaction of members with their own species in a way to increase the fitness of all members. Ex: packs, colonies, hives, troops
  33. 33. Chapter 17 The History of Life
  34. 34. EQ: How do fossils help biologists understand the history of life on Earth: – How do scientists use fossils to study Earth’s history? – What are some patterns in which evolution has occurred? – How fast does evolution take place?
  35. 35. Earth’s Early Atmosphere • Over time photosynthetic bacteria became common in the sea which started adding oxygen to the atmosphere • Next, oxygen gas started accumulating in the atmosphere which decreased the hydrogen sulfide and methane and eliminating most anaerobic organism but increased aerobic organisms
  36. 36. • The ozone layer started to form to provide protection from ultraviolet rays • Some organisms evolved ways of using oxygen for respiration and greater energy production • With more energy available, eukaryotes evolved in the sea and then on land • The eukaryotic cells aggregated into multicellular organisms and the evolution of the diversity of life was well on its way
  37. 37. Miller and Urey Experiment Carl Sagan Explains Miller-Urey Experiment: http://www.youtube.com/watch?v=79o6xzMfzKg Miller-Urey Experiment Animation: http://www.youtube.com/watch?v=iahBQolXQH8 **Mixtures of the organic compunds necessary for life could have arisen from simpler compounds on present on a primitive Earth. **Found that life arose from non-life. Is this true?
  38. 38. Fossil • Preserved remains of ancient organisms • http://www.neok12.com/php/watch.php? v=zX076e0e6d5a7b775b0d7a41&t=Fossil s
  39. 39. Fossil Record Information about past life that has been obtained from fossils
  40. 40. 1. Most organisms that have ever lived are now extinct 2. fossils occur in a particular order in the rock layer 3. groups of organisms have changed over time
  41. 41. Extinct A species that has completely died out Extant Species that still survive
  42. 42. Where do most fossils form? Most fossils form in sedimentary rock as weight compresses layers of sediment in bodies of water
  43. 43. • Not all parts of animals become fossilized. • Fossilization activity
  44. 44. http://www.ucmp.berkeley.edu/education/e xplorations/tours/fossil/5to8/Intro.html
  45. 45. What are some patterns in which evolution has occurred?
  46. 46. Mass Extinction Many types of living things become extinct in a short period of time Ex: Dinosaurs Asteroid hitting Earth at Chicxulub Mexico on the Yucatan peninsula ????? http://www.neok12.com/php/watch.php? v=zX060c4178075b5f7f7e6663&t=Prehist oric-Animals
  47. 47. How fast does evolution take place?
  48. 48. Gradualism A model of evolution which theorizes that most speciation is slow, uniform and gradual.
  49. 49. Punctuated Equilibrium Long period in which a species undergoes little to no change, interrupted by relatively brief periods of sudden change
  50. 50. Catastrophism The principle that events in the past occurred suddenly and were caused by different mechanisms than those operating today

×