chapter 16.1 introduction to evolution and evidence
TRANSCRIPT
LAMARK’s explanation on evolutionStructures • Vestigial Structures
• Adaptation • Variation
• Key Concepts • Who was Darwin and what was
his theory on evolution? • How structural and
physiological structures relate to evolution?
How many scientists are involved in developing the theory of evolution?
William Bateson Carolus Linneaus
George Buffon Charles Lyell
Hugo de Vries Ernst Mayr
Theodosius Dobzhanky Gregor Mendel
J.B.S. Haldane George Simpson
James Hutton Alfred Russel Wallace`
Thomas Huxley Alfred Wagner
What kinds of sciences did these scientists study? • Biology • Paleontology • Geology • Genetics • Botany • Naturalists • Microbiology • Biochemistry • Molecular chemistry • Ecology • Chemistry
When did the theory of evolution begin to develop? • Late 1600’s with John Ray
• Major contribution was his writings called Historia Plantarum
• Rejected the system of dichotomous division where species were classified by a preconceived type of system
• Instead, plants were classified by similarities and differences from observation
• Coined the term “species”
• 1859 • So about 200 years
after Ray
Look at the drawings carefully then answer the following questions…
1) What is the main difference you notice about the Galápagos finches?
2) Why do you think this difference exists?
Natural Selection and the Evidence for Evolution (16.1)
DEFINITION OF EVOLUTION:
• change over time: the process by which modern organisms have descended from ancient organisms.
Portrait of Darwin in 1840 (Darwin 65 years old) (31 years old)
The Life of Charles Darwin
Portrait of Darwin in 1840 (Darwin 65 years old)
(31 years old)
• Born 1809 (England)
• Completed college after studying to become a doctor but could not stand sight of blood …
• Set sail on 5 year voyage on H.M.S., Beagle in 1831 as the natural historian for expedition.
The Life of Charles Darwin
• Made extensive drawings and notes on the trip but also collected many species of plants and animals.
• Began to OBSERVE that animals were well adapted to their environments, (wondered why were different animals found in areas that appeared to be similar in climate? and some survived while others did not?)
• Argentina • Australia • Europe All had grasslands but very different
animals
The Life of Charles Darwin
• He collected fossils. • noticed some looked like living organisms • others looked like nothing he had ever seen before
• Were these related to the living (present day) organisms?
• Why did some organisms disappear altogether?
Where are the Galapagos?
Organisms Darwin Observed on the Galapagos • Land Tortoise = different shaped carapace (shell)
depending what island they inhabited.
• Finches = different shaped beaks depending on environment in which they lived.
• he realized that characteristics of many animals and plants varied noticeably among the different islands of the Galapagos.
• On the journey home he began to pose the question… • Could animals on the different islands once
have been members of the same species?
Those Who Influenced Darwin Hutton (Geologist)
• Geologic processes operate extremely slowly (take millions of years!)
• therefore, the earth is very old
Lyell (Geologist) • Scientists must explain past events in terms of
processes that they can actually observe • processes that shaped the Earth millions of years ago
continue to shape present day Earth • this explained how geological features can be built or
torn down over long periods of time.
Darwin wondered…
• If the earth could change over time, could life change as well?
• Also: it must have taken many, many years for life to change the way Darwin had in mind
• This would only be possible if the earth was very old…
Those Who Influenced Darwin
growth of human populations • if populations continue to grow unchecked,
they will run out of resources (food/shelter)
Variation & Adaptation
2 IMPORTANT CONCEPTS TO HELP US UNDERSTAND THE PROCESS OF
EVOLUTION:
ADAPTATION: inherited characteristic that increases an organism's chances of survival
Give me an example, PLEASE!!
EXAMPLES OF ADAPTATIONS!
How do they help polar
bear’s survive?
those of the polar bear?
What are some adaptations of a
cactus?
What about this desert plant?
What helps this kelp crab survive? (It lives on the kelp in the ocean.)
What the heck are these?
EVIDENCE FOR EVOLUTION 1) Fossils: evidence of once-living things (shells, casts,
bones, teeth, imprints)
show a succession of forms through a vast span of time
progressive changes based on the order they were buried in sedimentary rock few fossils / species many fossils/ species simple organisms complex organisms
EVIDENCE FOR EVOLUTION
2) Biogeography and age of the earth: distribution of plants & animals
13 species of finches on the 13 Galapagos Islands
57 species of kangaroos…
2) Biogeography and age of the earth:
Radioactive dating tells us the earth is about 4.6 billion years old
Rate of motion of tectonic plates
3) Adaptations: Evidence for Evolution
MIMICRY: one species resembles another
CAMOUFLAGE: enables species to blend with their surroundings
PHYSIOLOGICAL: ability to resist disease or drought
4) “Artificial Selection” 4) Applied Genetics ("artificial selection"):
Darwin noticed that farmers “selected” the best crops, animals – he wondered if there could be a “selective” force in nature
today we see DDT-resistant insects; antibiotic-resistant bacteria
5) Anatomical Structures: Evidence for Evolution
Homologous Structures = shared common anatomical or biochemical traits ex: " forearm bones”
• structures that develop from the same clumps of cells • later develop into structures that have different forms and
functions
• arms, flippers, & wings look very similar at the beginning of development, but differ as the animal matures
• The function differs as well!
Vestigial Structures: structures that no longer serve a purpose in an organism ex: wisdom teeth, tailbone, appendix, nictitating membrane, some pythons & boa constrictors have tiny leftover leg bones (and whales!) koala's have a large functioning appendix (eat primarily plant materials)
6) Embryological Development • Similarities of vertebrate organisms in early
stages of development • All animal development begins in the same way
(from the same ball of cells) • BUT recognizable features for that species develop
as the organism grows
•
7) Cellular and Molecular Evidence: Cellular Evidence • All organisms are made of cells
• consist of membranes filled with water containing genetic material, proteins, lipids, carbohydrates, salts and other substances
7) Cellular and Molecular Evidence
Molecular Evidence • the DNA code links all life on Earth to a
common ancestor • DNA and RNA = simple four-base code that
provides the recipe for all living things • Transfer genetic material from the cell of one
living thing to the cell of another • the recipient would follow the new instructions as if
they were its own • EX: Roundworms share 25% of their genes with humans.
Protein Sequence Similarities!
• Fossil record • Biogeography and age of the earth
(using radioactive dating) • Adaptations • Artificial Selection • Homologous structures and vestigial organs • Embryology • Cellular and Molecular Evidence
Chapter 16.1 Introduction to Evolution and Evidence
How many scientists are involved in developing the theory of evolution?
What kinds of sciences did these scientists study?
When did the theory of evolution begin to develop?
Slide Number 5
Slide Number 6
DEFINITION OF EVOLUTION:
Slide Number 9
Where are the Galapagos?
Those Who Influenced Darwin
Slide Number 21
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
EVIDENCE FOR EVOLUTION
Slide Number 33
Slide Number 34
Slide Number 35
EVIDENCE FOR EVOLUTION
Slide Number 37
Slide Number 38
4) “Artificial Selection”
Slide Number 41
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
6) Embryological Development
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 55
Slide Number 56
• Key Concepts • Who was Darwin and what was
his theory on evolution? • How structural and
physiological structures relate to evolution?
How many scientists are involved in developing the theory of evolution?
William Bateson Carolus Linneaus
George Buffon Charles Lyell
Hugo de Vries Ernst Mayr
Theodosius Dobzhanky Gregor Mendel
J.B.S. Haldane George Simpson
James Hutton Alfred Russel Wallace`
Thomas Huxley Alfred Wagner
What kinds of sciences did these scientists study? • Biology • Paleontology • Geology • Genetics • Botany • Naturalists • Microbiology • Biochemistry • Molecular chemistry • Ecology • Chemistry
When did the theory of evolution begin to develop? • Late 1600’s with John Ray
• Major contribution was his writings called Historia Plantarum
• Rejected the system of dichotomous division where species were classified by a preconceived type of system
• Instead, plants were classified by similarities and differences from observation
• Coined the term “species”
• 1859 • So about 200 years
after Ray
Look at the drawings carefully then answer the following questions…
1) What is the main difference you notice about the Galápagos finches?
2) Why do you think this difference exists?
Natural Selection and the Evidence for Evolution (16.1)
DEFINITION OF EVOLUTION:
• change over time: the process by which modern organisms have descended from ancient organisms.
Portrait of Darwin in 1840 (Darwin 65 years old) (31 years old)
The Life of Charles Darwin
Portrait of Darwin in 1840 (Darwin 65 years old)
(31 years old)
• Born 1809 (England)
• Completed college after studying to become a doctor but could not stand sight of blood …
• Set sail on 5 year voyage on H.M.S., Beagle in 1831 as the natural historian for expedition.
The Life of Charles Darwin
• Made extensive drawings and notes on the trip but also collected many species of plants and animals.
• Began to OBSERVE that animals were well adapted to their environments, (wondered why were different animals found in areas that appeared to be similar in climate? and some survived while others did not?)
• Argentina • Australia • Europe All had grasslands but very different
animals
The Life of Charles Darwin
• He collected fossils. • noticed some looked like living organisms • others looked like nothing he had ever seen before
• Were these related to the living (present day) organisms?
• Why did some organisms disappear altogether?
Where are the Galapagos?
Organisms Darwin Observed on the Galapagos • Land Tortoise = different shaped carapace (shell)
depending what island they inhabited.
• Finches = different shaped beaks depending on environment in which they lived.
• he realized that characteristics of many animals and plants varied noticeably among the different islands of the Galapagos.
• On the journey home he began to pose the question… • Could animals on the different islands once
have been members of the same species?
Those Who Influenced Darwin Hutton (Geologist)
• Geologic processes operate extremely slowly (take millions of years!)
• therefore, the earth is very old
Lyell (Geologist) • Scientists must explain past events in terms of
processes that they can actually observe • processes that shaped the Earth millions of years ago
continue to shape present day Earth • this explained how geological features can be built or
torn down over long periods of time.
Darwin wondered…
• If the earth could change over time, could life change as well?
• Also: it must have taken many, many years for life to change the way Darwin had in mind
• This would only be possible if the earth was very old…
Those Who Influenced Darwin
growth of human populations • if populations continue to grow unchecked,
they will run out of resources (food/shelter)
Variation & Adaptation
2 IMPORTANT CONCEPTS TO HELP US UNDERSTAND THE PROCESS OF
EVOLUTION:
ADAPTATION: inherited characteristic that increases an organism's chances of survival
Give me an example, PLEASE!!
EXAMPLES OF ADAPTATIONS!
How do they help polar
bear’s survive?
those of the polar bear?
What are some adaptations of a
cactus?
What about this desert plant?
What helps this kelp crab survive? (It lives on the kelp in the ocean.)
What the heck are these?
EVIDENCE FOR EVOLUTION 1) Fossils: evidence of once-living things (shells, casts,
bones, teeth, imprints)
show a succession of forms through a vast span of time
progressive changes based on the order they were buried in sedimentary rock few fossils / species many fossils/ species simple organisms complex organisms
EVIDENCE FOR EVOLUTION
2) Biogeography and age of the earth: distribution of plants & animals
13 species of finches on the 13 Galapagos Islands
57 species of kangaroos…
2) Biogeography and age of the earth:
Radioactive dating tells us the earth is about 4.6 billion years old
Rate of motion of tectonic plates
3) Adaptations: Evidence for Evolution
MIMICRY: one species resembles another
CAMOUFLAGE: enables species to blend with their surroundings
PHYSIOLOGICAL: ability to resist disease or drought
4) “Artificial Selection” 4) Applied Genetics ("artificial selection"):
Darwin noticed that farmers “selected” the best crops, animals – he wondered if there could be a “selective” force in nature
today we see DDT-resistant insects; antibiotic-resistant bacteria
5) Anatomical Structures: Evidence for Evolution
Homologous Structures = shared common anatomical or biochemical traits ex: " forearm bones”
• structures that develop from the same clumps of cells • later develop into structures that have different forms and
functions
• arms, flippers, & wings look very similar at the beginning of development, but differ as the animal matures
• The function differs as well!
Vestigial Structures: structures that no longer serve a purpose in an organism ex: wisdom teeth, tailbone, appendix, nictitating membrane, some pythons & boa constrictors have tiny leftover leg bones (and whales!) koala's have a large functioning appendix (eat primarily plant materials)
6) Embryological Development • Similarities of vertebrate organisms in early
stages of development • All animal development begins in the same way
(from the same ball of cells) • BUT recognizable features for that species develop
as the organism grows
•
7) Cellular and Molecular Evidence: Cellular Evidence • All organisms are made of cells
• consist of membranes filled with water containing genetic material, proteins, lipids, carbohydrates, salts and other substances
7) Cellular and Molecular Evidence
Molecular Evidence • the DNA code links all life on Earth to a
common ancestor • DNA and RNA = simple four-base code that
provides the recipe for all living things • Transfer genetic material from the cell of one
living thing to the cell of another • the recipient would follow the new instructions as if
they were its own • EX: Roundworms share 25% of their genes with humans.
Protein Sequence Similarities!
• Fossil record • Biogeography and age of the earth
(using radioactive dating) • Adaptations • Artificial Selection • Homologous structures and vestigial organs • Embryology • Cellular and Molecular Evidence
Chapter 16.1 Introduction to Evolution and Evidence
How many scientists are involved in developing the theory of evolution?
What kinds of sciences did these scientists study?
When did the theory of evolution begin to develop?
Slide Number 5
Slide Number 6
DEFINITION OF EVOLUTION:
Slide Number 9
Where are the Galapagos?
Those Who Influenced Darwin
Slide Number 21
Slide Number 23
Slide Number 24
Slide Number 25
Slide Number 26
Slide Number 27
Slide Number 28
Slide Number 29
Slide Number 30
Slide Number 31
EVIDENCE FOR EVOLUTION
Slide Number 33
Slide Number 34
Slide Number 35
EVIDENCE FOR EVOLUTION
Slide Number 37
Slide Number 38
4) “Artificial Selection”
Slide Number 41
Slide Number 43
Slide Number 44
Slide Number 45
Slide Number 46
Slide Number 47
Slide Number 48
6) Embryological Development
Slide Number 50
Slide Number 51
Slide Number 52
Slide Number 55
Slide Number 56