2. Chapter Menu Lesson 1: Fossils and Evolution
Lesson 2: Biological Evidence
Lesson 3: Evolution and Plate Tectonics
Lesson 4: Classifying Organisms
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3. 6.1 Fossils and Evolution fossil paleontologist permineralization mold
cast
fossil record

4. 6.1 Fossils and Evolution
What are fossils?
Fossils are the naturally preserved remains, imprints, or traces of organisms that lived long ago.
Includes bones, shells, and footprints.
Microfossils can only be seen under a microscope.
Fossils

5. What are fossils? (cont.)
6.1 Fossils and Evolution
What are fossils? (cont.)
A paleontologist is a scientist who studies fossils.
They determine:
the relationships among organisms
the approximate times when life first appeared on Earth
when organisms became extinct

6. 6.1 Fossils and Evolution
When do fossils form?
Decomposition—breaking down into substances that can be used by other organisms—is part of an organism’s life cycle.
For an organism to become a fossil, it must be protected from decomposers, scavengers, and environmental factors.

7. How are fossils formed? Fossils only form under certain conditions.
6.1 Fossils and Evolution
How are fossils formed?
Fossils only form under certain conditions.
Most frequently found fossils are preserved hard structures, but occasionally soft structures are preserved.

8. 6.1 Fossils and Evolution
Permineralization
When substances inside the tiny spaces of dead organisms decompose, water seeps in and deposits minerals, such as silica or calcite.
This process—permineralization—forms a strong, rock-like fossil.

9. 6.1 Fossils and Evolution
Replacement
The hard parts of an organism are replaced by minerals in replacement.
Only the shape of the original organism remains.

10. 6.1 Fossils and Evolution
Carbonization
If a dead organism is quickly buried under conditions without oxygen, the elements of the living tissue are removed.
A thin carbon film remains and is compressed by sediment, preserving the image of the organism on a rock.

11. 6.1 Fossils and Evolution
Molds and Casts
Molds can be the imprints from a shell or the skin of an animal.
Molds fill in with sediment that hardens into rock creating casts.
No parts of the original organism remain.

12. 6.1 Fossils and Evolution
Original Material
Organisms preserved in materials such as amber are called original material fossils.
They are rare and provide much information because none of the hard or soft structures have been altered or replaced.

13. What do fossils tells us?
6.1 Fossils and Evolution
What do fossils tells us?
Much of the evidence for the pattern of evolutionary relationships comes from fossils.
Scientists also study fossils to understand some processes and rates of evolution.
Fossils provide a record of different organisms that lived in the past.

14. 6.1 Fossils and Evolution
Relative Fossil Ages
Generally, younger fossils are in shallow sedimentary rock layers and older fossils are in deeper layers.
In this way, fossils can be compared by relative age and the changes to species can be documented.

15. Species and Environmental Changes
6.1 Fossils and Evolution
Species and Environmental Changes
The fossil record is all the known fossils and their placements in the formation of rocks and positions in time.
The fossil record is evidence of the evolution of plants and animals, and their extinction.

16. Species and Environmental Changes
6.1 Fossils and Evolution
Species and Environmental Changes
(cont.)
Fossils provide evidence of how life and environmental conditions have changed throughout time.
Scientists use fossils to determine how organisms lived, what they ate, and what kind of environment they lived in.
How can fossil and rock data determine when an organism lived?

17. 6.1 Fossils and Evolution A B C D
What describes the deposit of minerals into the tiny spaces that have decomposed in an organism?
A permineralization
B decomposition
C replacement
D molds
Lesson 1 Review

18. 6.1 Fossils and Evolution A B C D
What describes the preservation of the impression of an organism if no parts of the organism remain?
A carbonization
B replacement
C molds or casts
D original material
Lesson 1 Review

19. What are the most commonly found fossils? A original material
6.1 Fossils and Evolution A B C D
What are the most commonly found fossils?
A original material
B hard structures
C soft structures
D footprints
Lesson 1 Review

20. End of Lesson 1

21. 6.2 Biological Evidence comparative anatomy homologous structure
embryology

22. 6.2 Biological Evidence
Comparative Anatomy
Comparative anatomy is the study of similarities and differences in the physical structures of organisms.
Besides fossils, comparative anatomy supports the theory of evolution by natural selection.

23. Structures in Organisms
6.2 Biological Evidence
Structures in Organisms
At some point in our pasts, humans, frogs, bats, birds, and cats all shared a common ancestor.

24. Homologous Structures
6.2 Biological Evidence
Homologous Structures
Parts of organisms that are similar in origin and structure are called homologous structures.
Are the result of evolution
Can indicate how closely two or more species share common ancestors

25. Homologous Structures (cont.)
6.2 Biological Evidence
Homologous Structures (cont.)
The bones in the upper limbs of these animals are homologous structures.

26. 6.2 Biological Evidence
Analogous Structures
Analogous structures appear similar, but have different ancestral origins.
The wings of birds and insects
Result from similar environmental conditions that produced similar natural selection outcomes

27. 6.2 Biological Evidence
Vestigial Structures
Another source of evidence for evolution is vestigial structures—structures that have no function in their present-day form.
Scientists hypothesize that the structures once functioned in an ancestor.

28. 6.2 Biological Evidence
Embryology
The science of the development of embryos from fertilization to birth is embryology.
The more closely related species are, the more features they share during development.
Shared similarities are best explained by the theory of common ancestors and evolution through natural selection.

29. 6.2 Biological Evidence
Molecular Biology
Data from molecular biology support the theory of evolution through natural selection.
The proteins of all organisms consist of countless arrangements of just twenty different amino acids.
Slight differences in cytochrome c molecules of organisms probably did not develop independently from different ancestral lines.

30. Molecular Biology (cont.)
6.2 Biological Evidence
Molecular Biology (cont.)

31. What describes the wings of an insect and a bird?
6.2 Biological Evidence A B C D
What describes the wings of an insect and a bird?
A analogous structures
B vestigial structures
C homologous structures
D embryology
Lesson 2 Review

32. Which types of structures have no function in their present-day form?
6.2 Biological Evidence A B C D
Which types of structures have no function in their present-day form?
A homologous structures
B vestigial structures
C analogous structures
D pharyngeal pouches
Lesson 2 Review

33. What do embryologists compare when studying embryos?
6.2 Biological Evidence A B C D
What do embryologists compare when studying embryos?
A physical structures
B proteins
C DNA sequence
D patterns of development
Lesson 2 Review

34. End of Lesson 2

35. 6.3 Evolution and Plate Tectonics
geographic isolation
convergent evolution

36. 6.3 Evolution and Plate Tectonics
Continental Drift
Acceptance of the continental drift hypothesis led to the development of the theory of plate tectonics.
As lithospheric plates move, they create environmental changes for the organisms that live in or near them.
The changes lead to the development of and extinction of species.

37. Continental Drift (cont.)
6.3 Evolution and Plate Tectonics
Continental Drift (cont.)

38. 6.3 Evolution and Plate Tectonics
Geographic Isolation
Geographic isolation occurs when populations of species are separated by a physical barrier.
Once separated, the populations might follow different evolutionary paths.

39. Darwin’s Observations
6.3 Evolution and Plate Tectonics
Darwin’s Observations
The results of geographic isolation prompted much of Darwin’s research.
Species on an island were more similar to those on the mainland even though the two environments were different.
These observations led to the idea of evolution by natural selection.

40. Geographic Isolation v. Convergent Evolution
6.3 Evolution and Plate Tectonics
Geographic Isolation v. Convergent Evolution
Sometimes distant locations with similar environmental conditions have species with similar traits.
The species developed independently but under similar conditions.
Convergent evolution results in structural and functional similarities.

41. B geographic isolation C convergent evolution
6.3 Evolution and Plate Tectonics A B C D
What term describes the separation of populations by physical barriers?
A continental drift
B geographic isolation
C convergent evolution
D theory of plate tectonics
Lesson 3 Review

42. What did Darwin observe about geographically isolated populations?
6.3 Evolution and Plate Tectonics A B C D
What did Darwin observe about geographically isolated populations?
A Species on distant islands with similar environmental conditions were similar.
B Species on islands and the mainland had undergone convergent evolution.
C Species on islands were similar to those on the mainland even though the environments were different.
D Species on the islands were more similar to each other than species on one island and the mainland.
Lesson 3 Review

43. A geographic isolation B recent common ancestry C convergent evolution
6.3 Evolution and Plate Tectonics A B C D
What is the term for how very distantly related species can appear similar?
A geographic isolation
B recent common ancestry
C convergent evolution
D natural selection
Lesson 3 Review

44. End of Lesson 3

45. 6.4 Classifying Organisms
systematics

46. Historic Classification Systems
6.4 Classifying Organisms
Historic Classification Systems
Aristotle categorized things as animals, plants, or minerals, and then according to where they lived—air, land, or sea.
Linnaeus developed a classification system that grouped organisms by similar physical structures, from kingdom to species.
Species have the greatest number of traits in common and can breed and produce fertile offspring.

47. Naming and Grouping Species
6.4 Classifying Organisms
Naming and Grouping Species
Linnaeus also developed a system for naming species that is still used.
The two-word scientific name of an organism is its species name.

48. 6.4 Classifying Organisms
Determining Kingdom
Basic features such as cell type, presence of a cell wall, or single-celled versus multicellular define a kingdom.
Eubacteria
Archeabacteria
Protists
Fungi
Plantae
Animalia

49. Modern Methods of Classification
6.4 Classifying Organisms
Modern Methods of Classification
The modern study of classification—systematics—uses DNA and molecular biology to identify related organisms.
The more shared DNA sequences two species have, the more recent ancestor they probably share.

50. Modern Methods of Classification (cont.)
6.4 Classifying Organisms
Modern Methods of Classification (cont.)
Scientists use haplotypes—samples of 1000 base pairs—to compare DNA sequences among organisms.
DNA hybridization measures the percentages of DNA that are the same between two organisms.

51. Modern Methods of Classification (cont.)
6.4 Classifying Organisms
Modern Methods of Classification (cont.)
Molecular biology led to a new level of classification—domain—based on differences in a particular genetic sequence.
Bacteria
Archaea
Eukarya

52. Modern Methods of Classification (cont.)
6.4 Classifying Organisms
Modern Methods of Classification (cont.)
As more sophisticated techniques are developed, the classification system will become more refined.

53. Modern Methods of Classification (cont.)
6.4 Classifying Organisms
Modern Methods of Classification (cont.)

54. What was Linnaeus’ classification system based on?
6.4 Classifying Organisms A B C D
What was Linnaeus’ classification system based on?
A whether things were plant, animal, or mineral
B where organisms lived—air, water, or land
C similar DNA sequences
D similar physical structures
Lesson 4 Review

55. Similar genera are classified into the same ____. A species B order
6.4 Classifying Organisms A B C D
Similar genera are classified into the same ____.
A species
B order
C class
D family
Lesson 4 Review

56. 6.4 Classifying OrganismsB C D
What approach measures the percentage of DNA that is similar between two organisms?
A DNA hybridization
B DNA sequencing
C haplotypes
D systematics
Lesson 4 Review

57. End of Lesson 4

58. Chapter Resources Menu
Chapter Assessment
California Standards Practice
Image Bank
Science Online
Interactive Table
Virtual Lab
BrainPOP
Click on a hyperlink to view the corresponding feature.

59. What does a paleontologist study? A DNA B classification of organisms
C fossils
D embryos
Chapter Assessment 1

60. What does NOT explain the gaps in the fossil record? B C D
What does NOT explain the gaps in the fossil record?
A Most organisms decay before fossilization.
B Fossils are unreliable for studying Earth’s history.
C Some fossils have not been found yet.
D Geological processes destroy fossils.
Chapter Assessment 2

61. A B C D
What describes the study of similarities and differences in the structure of organisms?
A embryology
B systematics
C molecular biology
D comparative anatomy
Chapter Assessment 3

62. Analogous structures an indication of ____. A convergent evolution B C D
Analogous structures an indication of ____.
A convergent evolution
B a common ancestor
C continental drift
D geographic isolation
Chapter Assessment 4

63. What is currently the highest level of classification? A animalia B C D
What is currently the highest level of classification?
A animalia
B domain
C kingdom
D order
Chapter Assessment 5

64. SCI 4.c A B C D
What does the depth of a fossil in the rock layer tell us about the fossil?
A how old it is
B how it died
C how it evolved
D how it lived
CA Standards Practice 1

65. What does the fossil record NOT indicate?
SCI 4.e A B C D
What does the fossil record NOT indicate?
A Species have evolved through natural selection.
B Most species that lived on Earth are extinct.
C Environmental conditions on Earth have not changed much.
D In Earth’s early history, life was less complex.
CA Standards Practice 2

66. SCI 3.c A B C D
Which of the following does not provide independent evidence for the theory of evolution through natural selection?
A fossil record
B comparative anatomy
C systematics
D molecular biology
CA Standards Practice 3

67. A convergent evolution B homologous structures C environmental changes
SCI 4.f A B C D
How does the movement of lithospheric plates possibly lead to the evolution of a new species?
A convergent evolution
B homologous structures
C environmental changes
D continental drift
CA Standards Practice 4

68. Which of the following is not a kingdom? A protista B fungi C eukaya
SCI 3.d A B C D
Which of the following is not a kingdom?
A protista
B fungi
C eukaya
D animalia
CA Standards Practice 5

69. Image Bank

70. Interactive Table

71. End of Resources