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Evolution > Lec 1 > Flashcards

Lec 1 Flashcards

1
Q

What is Science?

A

“Systematic study of the structure and behavior of the physical and natural world through observation and experimentation”

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2
Q

Science is based on experimentation and observation of _________________

A

Natural phenomena

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3
Q

Science is based on _____________ - hypotheses that can be shown to be NOT TRUE based on data

A

Falsifiable hypotheses

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4
Q

What explanations for phenomena are beyond the scope of science?

A

Supernatural or faith-based explanations

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5
Q

Why is it incorrect to say it’s “Just a Theory”?

A

Scientific theories must be based on supported hypotheses (facts)

Scientific theories must be falsifiable

Scientific theories are the most reliable, rigorous, and comprehensive form of scientific knowledge

Scientific theories are built on MOUNTAINS of theory and MUST be falsifiable; VERY rigorous

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6
Q

Theory vs. scientific theory

A

Theories are generalized explanations of how things work

Scientific theories are built on mountains of data

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7
Q

An hypothesis is:

A

A testable idea

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8
Q

Theory

A

In every day life, it’s used as “opinion, hunch, or guess”

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9
Q

Scientific Theory

A

Supported by many facts; must be supported by multiple tests

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10
Q

Scientific Law

A

NOT the same as Scientific Theory

Theory explains the why, Law explains the WHAT

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11
Q

Well-known scientific theories

A

Theory of Earth Rotation (1613)

Theory of Blood Circulation (1628)

Theory of Gravity (1687)

Cell Theory (1839) [1891*]

Germ Theory of Disease (1020*) (1856)

Theory of Evolution (1859)

Theory of Plate Tectonics (1920)

Theory of Relativity (1920)

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12
Q

Evolutionary Theory

A

1859

General explanation for biodiversity on earth supported by evidence

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13
Q

Origins and Development of Evolutionary Theory

A

Darwin was not the first to propose the idea that species can change through time

His Theory of Descent with Modification by Natural Selection was hugely influential in the development of the modern Theory of Evolution

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14
Q

What is evolution?

A

Evolution is change over time… specifically the change in ALLELE frequencies over time

Darwin did not initially describe evolution as changes in allele frequencies. He conceptualized it as changes in phenotype - the outward appearance of an organism.

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15
Q

Evolution is the foundation of out understanding of __________

A

ALL biological processes

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16
Q

“Nothing in biology makes sense except in the light of _______” - ________

A

Evoltuion

Theodosius Dobzhansky

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17
Q

Scientific Questions asked by pre-Darwinian thinkers

A

What separates science and mythology?

How should scientists draw conclusions about the natural world?

How does the natural world change?

Why is the world filled with a diversity of life forms?

Where do species come from?

Why are organisms so well-suited to their environments?

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18
Q

Methodological Naturalism

A

Every human culture has creation myths to explain how the wordl came to be

Greek philosophers such as Anaximander (610-546 BC) attempted to develop ideas of a natural world driven by physical laws

These were driven by PHYSICAL LAWS

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19
Q

Methodological Naturalism: Anaximander’s Cosmology

A

The heavenly bodies (planets) are not divine

Suggested that the sun, moon, and stars are physical objects

Stated that heavenly bodies rotate around the earth (not true)

Set the stage for natural, rather than supernatural, explanations for phenomena

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20
Q

Power of Methodological Naturalism

A

Natural explanations for natural processes are testable, because we can observe and manipulate these processes

Supernatural explanation are not testable because supernatural causation cannot be observed or manipulated

We call it “methodological” because it provides a method for seeking scientific explanations of the world

These features separate science from mythology

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21
Q

Hypothesis Testing

A

Aristotle (384-322 BC) introduced the idea of HYPOTHESIS TESTING

This means principles must agree with facts - not the other way around

We should be able to observe and manipulate the processes underlying out hypotheses

In facts and principles do not agree, we must re-evaluate our principles

Principles MUST agree with facts; if a fact contradicts a principle, you change the hypothesis, NOT the fact

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22
Q

Basis of Hypothesis Testing

A
  • Scientific hypotheses require causal explanations and must be rigorous
  • Scientific hypotheses must be falsifiable; must be able to show that they are not true
  • Hypothesis testing requires a control
  • Hypothesis testing must be repeatable

If we can’t get the same results in other tests, it is not a good hypothesis

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23
Q

A hypothesis is a _______ based on the knowledge obtained while formulating a question

A

Conjecture

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24
Q

Control

A

Un-manipulated condition

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25
Q

Origins of the scientific process

A

Testing hypotheses and the application of natural and mathematical laws and logic allow thinkers to move from facts to general principles

Ibn al-Haytham (965-1040AD), an Arab mathematician and philosopher, is often considered the first to employ systematic approach to varying experimental conditions in his studies of optics

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26
Q

Classic test of hypotheses about origin of life

A

Ideas of spontaneous generation of life existed in the ancient world and persisted for thousands of years

Francesco Redi used a modern experiment to test this idea in 1668

Hypothesis: Flies generate spontaneously in meat

Predictions: If hypothesis supported, there should be flies in all treatment jars

There was an idea that flies spontaneously generate out of meat because any time a piece of meat is out, flies appear on it quickly

Flies only appeared in open containers, maggots, too

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27
Q

Which of these is NOT a testable, falsifiable hypothesis?

a) The disease COVID-19 is caused by the coronavirus SARS-CoV-2
b) Transmission of the SARS-CoV-2 virus occurs primarily through respiratory droplets
c) The COVID-19 pandemic is punishment for human destruction of the environment
d) The SARS-CoV-2 virus emerged from a single transmission from animals to humans, rather than many transmission events

A

The COVID-19 pandemic is punishment for human destruction of the environment

We cannot test the “idea” that the pandemic is punishment of any sort; can’t collect data that can falsify this idea

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28
Q

Early ideas about Evolution can be tracked to 3 philosophers

A

Anaximander (611-547 BC), Empedocles (492-432 BC) and Lucretius (99-55 BC) proposed that all living things were related and that they had changed over time

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29
Q

Who demonstrated that things change over time?

A

Aristotle in his Scala Naturae explained the advancement of living things from inanimate matter to plants, then animals and finally man

It was thousands of years before these ideas were widely accepted

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30
Q

Early ideas about Evolution

A

Zhuangzi (circa 300 BC) proposed that life forms have an innate ability to transform and adapt to their surroundings

he also indicated that humans are subject to this process

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31
Q

Al-Jahiz (781-869)

A

Arab scholar interested in natural history proposed the first modern theory of evolution in the Book of Animals

Largely ignored by the western world, but possibly inspired Darwin

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32
Q

Al-Jahiz’s Theory of Evolution

A

Animals engage in a struggle for existence, for resources, to avoid being eaten and to breed
-Many of these ideas are similar to MARKIAN evolution

Environmental factors influence organisms to develop new characteristics to ensure survival, thus transforming into new species

Animals that survive to breed can pass on their successful characteristics to offspring

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33
Q

Early ideas about evolution: Avicenna

A

980-1037

Persian scholar and philosopher

One of the most important scientists in history - discovered the nature of infection diseases

Proposed for the first time the Law of Superposition: Older layers of sediment are covered by younger layers

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34
Q

Law of Superposition

A

Older layers of sediment are covered by younger layers

Helps us determine AGE of earth

Can age sediment based on how deep they are

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35
Q

Setting the stage for evolutionary theory: gradual change over time

A

Early thinkers assumed the earth was young

Leonardo da Vinci (1452 - 1519) calculated the sedimentation rates in the Po River of Italy, and concluded it took 200,000 years to form some nearby rock deposits
-Using superposition to age it, lower layers will be older than layers higher up in rock

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36
Q

Setting the stage for evolutionary theory: Uniformitarianism (gradual change over time)

A

First proposed by George-Louis Leclerc, James Hutton and refined by Charles Lyell in the 1800’s

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37
Q

Basis of Uniformitarianism

A

Idea that slow acting processes over long periods of time can produce dramatic results

Contrasted with prevailing view of “catastrophism”

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38
Q

Catastrphism

A

Geological features emerge from major, catastrophic events

i.e. the Grand Canyon formed by SLOW PROCESSES, not catastrophe

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39
Q

Uniformitarianism

A

Important because accepting gradual change means that these changes are observable and could be tested experimentally

Difficult to observe, measure, and manipulate changes that occur due to unpredictable natural catastrophes

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40
Q

Setting the stage for evolutionary theory: The struggle for existence

A

Erasmus Darwin (1731-1802), grandfather of Charles Darwin, discussed the notion of a STRUGGLE FOR EXISTENCE:

  • Organisms are in a constant struggle to obtain resources and use those resources to produce offspring
  • Humans descended form another primate
  • Failed to connect struggle for existence to evolutionary change over time

Even though he observed competition, he did NOT see the struggle for existence as a driver for evolution (couldn’t prove this hypothesis)

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41
Q

Setting the stage for evolutionary theory: Species change through time

A

Robert Chambers (1802-1871) in his Vestiges of the Natural History of Creation highlighted two critical points about the fossil record:

  • The species composition changed through time
  • -You don’t find identical species in different layers; in history, there has been some change in the species present on earth
  • This change is slow, gradual and unlinked to catastrophes
  • -Support for Uniformitarianism

Hypothesized new species arise from old species

Did not explain WHY new species arise (answered by Charles Darwin)

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42
Q

Setting the stage for evolutionary theory: Organisms are well-suited to their environments

A

William Paley (1743-1805) in his Natural Theology discussed the metaphor of the Watchmaker

Organisms are like watches, if one piece is absent of misplaced the watch will fail to function

Recognized that organisms were well-suited to their environments

He assumed a supernatural creator must have put them together; NOT a testable hypothesis

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43
Q

Setting the stage for evolutionary theory: Adaptation

A

Jean-Baptiste Lamarck (1744-1829) in his Zoological Philosophy proposed this Theory of Adaptation

More complex species descend gradually from older, less complex species

This occurs through a process of adaptation, in which organisms acquire new traits during their lifetimes

Formation of complex from more simple due to adaptation

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44
Q

Lamarck: Inheritance of acquired characteristics

A

Hypothesized that an organism can acquire characteristics during its lifetime and pass them on to its offspring

-The long legs of shorebirds are the results of birds stretching their legs to avoid sinking in the mud

Connected PHENOTYPE ot environment

Idea: giraffes got long necks to reach leaves on tops of trees, passed on to offspring

This is INCORRECT, but this is the first time that a phenotype was connected to the environment

Phenotype - Lamarck

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45
Q

Key Vocabulary: Phenotype

A

The outward appearance of an organism

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46
Q

Setting the stage for evolutionary theory: More individuals are produced than can survive

A

Robert Malthus (1766-1834) argued that humans would outstrip the available resources necessary to sustain themselves, leading to population growth that would be checked by famine, war, and disease

Malthus came up with the idea that more individuals are produced than can survive Malthus was not a scientist

Applies to natural populations: Food supply is constant and population growth tends to be exponential

When resources are limited, the best suited organisms obtain more resources than the rest

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47
Q

Which is NOT a key component of early evolutionary thinking?

a) Survival of the fittest
b) Change in genotypes over time
c) The progression from simple to more complex and sophisticated forms over time
d) One species turning in to a different species

A

b) Change in genotypes over time

Genotypes were not yet discovered

48
Q

Major developments that PRECEDED Darwin

A

1) Shift from supernatural explanations to methodological naturalism in explaining the natural world

2) Shift from logic and reason to observation, testing, refutation
- Falsifiable hypotheses rather than spirituality

3) View world as in state of flux or change, rather than unchanging
- See world as old

4) Shift from catastrophism to uniformitarianism (gradual change over long periods of time)
5) Away from ideas of spontaneous generation and stasis to recognition that species come from other, related species
6) Organisms are suited to their environments and compete for resources

49
Q

Charles Darwin

A

Formulated Evolutionary Theory as we understand it today

From a wealthy family in England

Was in training to become a medical doctor, but found it boring

Preferred natural history and spent time collecting beetles and studying geology

50
Q

The voyage of the HMS Beagle

A

Darwin obtained a position as the ship’s naturalist on the HMS Beagle’s second voyages around the world form 1831-1836

He was 22 years old

Made extraordinary collections of plants, animals, and fossils

Shipped specimens back to England, recorded in journals

51
Q

Darwin after the Beagle

A

After the journey on the Beagle, Darwin began sifting through his journals and wrote a popular book, The Voyage of the Beagle

Struck by mockingbirds and tortoises in the Galapagos

Found support of Lyell’s ideas about uniformitarianism (gradual change over time) in his fossils

Published voluminously on orchids, coral reefs, barnacles, pigeons, corresponded widely with other scientists

Darwin worked on his ideas about natural selection for nearly 23 years
-Worked in secret at first

Was tormented by his ideas and afraid of their implications
-Knew ideas would be controversial that humans would be subject to same process (i.e. too unique)

Amassed extensive evidence for his ideas via experimentation and artificial selection

What caused Darwin to publish? Alfred Russel Wallace

52
Q

Alfred Russel Wallace

A

1823-1913

Came from working-class family

Spent many years in S American and Southeast Asia and published salvaged notes from his discoveries (lost notes in shipwrecks)

In 1854, went to study the natural history of Indonesia, where he contracted malaria

During fever, he wrote down his ideas on natural selection

53
Q

Darwin, Wallace, and Natural Selection

A

Darwin and Wallace independently discovered the role of natural selection in the formation of species

In 1858 Darwin received a letter from Wallace, in which Darwin’s unpublished theory of natural selection was described
-Darwin was a highly respected scientist in that time

Darwin and his colleagues arranged for Wallace’s papaer to be read at the July 1, 1858 meeting of the Linnaean Society, along with a letter on the same subject by Darwin
-Co-presented Darwin’s and Wallace’s work

54
Q

Darwin published __________ in 1859

A

The Origin of Species

His seminal work

55
Q

Darwin laid out entire theory of Natural Selection in _______-

A

ONE PARAGRAPH

The rest of his book amassed evidence to support ideas

56
Q

Theory of Natural Selection

A

More species are born than can survive = struggle for existence

Greater chance of survival for those that fit environment

57
Q

Darwin’s First Key Insight: Evolution by natural selection - 4 key Observations

A

1) Phenotypes vary within a population - variation in size, height, color, weight, etc.
2) More offspring are produced in a generation than can survive - Comes back to Malthus’ idea that is a population outstrips its food supply, not all can survive
3) Phenotypes are heritable (to some extent) - Strong principle of inheritance; if you have tall parents, you’re more likely to be tall
4) Some phenotypes will have better survival and become more prevalent in the population over time - Some phenotypes more likely to survive and reproduce more; favorable characteristics will become more prevalent over time

58
Q

Components of Natural Selection: Variation

A

Members of populations vary in the traits they display

59
Q

Components of Natural Selection: Inheritance

A

Offspring tend to resemble their parents

60
Q

Components of Natural Selection: Differential reproductive success

A

Brighter beetles are bitter and predators learn to avoid them. Bright beetles are more likely to survive and reproduce than duller-colored beetles

Result = Evolution by natural selection. Proportions of different variants in beetle population change over time

61
Q

Malthus’s ideas applied to nature

A

Difference between individuals produced in a generation and resources available is the potential for natural selection to act

The difference reflects the zone in which natural selection by resource limitation occurs and in which less-fit forms are unable to survive

62
Q

Darwin’s first key insight

A

“Nature” selects on variation in traits of individual organisms, because some variants are better suited to survival than others

Natural selection is then the differential survival of individuals who are best suited to their environment

Over time there will be enough heritable changes, resulting in a transformation of the original species into a new species similar to, but distinct from, its parent species

Process also referred to as “descent with modification”

63
Q

Descent with modification

A

Over time there will be enough heritable changes, resulting in a transformation of the original species into a new species similar to, but distinct from, its parent species

64
Q

What is Evolution?

a) Survival of the fittest
b) Change in genotypes and phenotypes over time
c) The progression from simple to more complex and sophisticated forms over time
d) One species turning in to a different species

A

b) Change in genotypes and phenotypes over time

This is the more supported definition now

65
Q

Darwin’s second key insight: Common ancestry

A

Common ancestry of all living things: Species resemble each other because they are descended from common ancestors

Noted by scholars LONG before Darwin that species resemble each other

Darwin theorized that all species descended from one common ancestor

66
Q

Common ancestry explains ___________

A

Clustering patterns in nature

Similar species cluster together hierarchically

All squirrels are more closely related to each other than any is to an antelope

A process of branches subdividing would naturally give rise to these hierarchies

67
Q

What is a species?

A

Dog breeds are VARIETIES of a species

68
Q

Varieties vs. Species

A

Selection on varieties was well accepted, but the jump to “new species” was a challenge for many critics - Breeder selects for certain varieties

To Darwin, the distinction between a “variety” and a “species” was arbitrary - A variety is an earlier form on the path to a species according to Darwin

If varieties are similar to species, we can recognize the concept of descent with modification

Darwin argued that the process of artificial vs. natural selection were essentially the same, with only the traits and the selective agents (humans vs. nature) different
-Humans may select for high milk production, nature may select for camo colors

69
Q

Central components of evolutionary theory

A

Species are not immutable - they may change through time

Species are not derived independently - they share common ancestors

Species change slowly - the earth is very old

Species are well-suited to their environments - this is caused by natural selection

70
Q

Consequences of evolutionary theory

A

Natural (as opposed to supernatural) explanation for origins and diversity of life on earth

Framework for studying and understanding commonalities and differences among all living things

71
Q

Lamarckian Evolution

A

Transformational process

i.e. Giraffe with short neck gets long neck IN ITS LIFETIME and passes on to offspring

Thought that organisms were well-suited to environment because they acquired traits in their lifetime (i.e. giraffes stretched up to reach leaves on trees = longer necks and passed on to offspring)

Individuals change WITHIN their lifetime to better suit environment

72
Q

Darwinian Evoluion

A

Variational process

CORRECT process of evolution

Individuals do NOT change within lifetime, the ones that are suited to environment are those that survive

73
Q

In Lamarck’s theory of evolution, species evolve:

A

Independently and in parallel

Linear progression

74
Q

In Darwin’s theory of evolution, species are:

A

Descended one from another to form a branching tree of life

Branching tree of life

75
Q

Lamarck

Variation is made to fit what an organisms wants or needs
(If an organism NEEDED to have a certain trait, Lamarck believed that it would get that trait in its lifetime)

A

Darwin

Variation exists naturally in populations
(Variation occurs naturally, organisms do NOT obtain characteristics they do not have int heir lifetime just because it is best suited to environment

76
Q

Lamarck

Individuals ACQUIRE characteristics in their lifetimes and transmit these characteristics to their offspring
(Individuals must acquire a characteristic to suit environment and pass on to offspring)

A

Darwin

Individuals that have characteristics beneficial in a particular environment pass those characters to their offspring
(Individuals already possessed a character and pass that character on to offspring)

77
Q

Lamarck

Organisms follow a directional, linear path of increasing complexity over time
Suggests a plan to evolution

A

Darwin

There is no “plan” - evolution is an undirected process
Individuals respond to prevailing environmental conditions

78
Q

Lamarck

No extinction

A

Darwin

Extinction
Extinction IMPORTANT in evolution

79
Q

Which one of these assertions is Darwinian and not Lamarckian?

a) An individual that acquired new characteristics in its lifetime is able to transmit them to its offspring
b) INdividual organisms evolve because they need to survive or use new resources
c) There is no extinction
d) Individuals better suited to their environment reproduce more than others and pass beneficial characteristics to their offspring

A

d) Individuals better suited to their environment reproduce more than others and pass beneficial characteristics to their offspring

80
Q

Broad classes of evidence supporting evolution

A

Artificial selection

Island radiations

The fossil record

Behavioral data

Morphological data

Embryological data

Molecular data

81
Q

Building the Evidence: Artificial Selecion

A

Darwin relied on ARTIFICIAL SELECTION to build evidence for natural selection
-Relied heavily on artificial selection to build evidence for natural selection; same process, different driver

By breeding certain varieties of an organism over others, humans can rapidly change the appearance and even the behavior of an organism

Pigeon breeding lead to a wide range in color variations, flying habits, behavior, and so on

Darwin argues that pigeon races would be considered different species or even genera if we did not know how they were produced

82
Q

Building the Evidence: Island Radiations

A

Observation of island organisms lead both Darwin and Wallace to breakthrough discoveries

Darwin influenced by Galapagos Islands; Wallace influenced by islands off Southeast Asia

After examining Darwin’s collections, ornithologist John Gould confirmed that what Darwin thought were many unrelated species were all finches and what he thought were varieties of mockingbirds were different species

On islands, radiation of species that occupy different niches

Mockingbirds look somewhat similar; proven to be different species

83
Q

Radiations on islands

A

Organisms fill available ecological space (‘niches”)

Radiations of many phenotypes and morphologies

Bushbaby - first primate to find its way to Madagascar; radiated into many different forms due to lack of predators

84
Q

Adaptive Radiations

A

Rapid diversification into many forms from a common ancestor

85
Q

Ecological analogues

A

Unrelated organisms display similar adaptations to the same ecological niches - kangaroos and cows both have 2 stomach chambers for fermenting grasses and other plants

Support for natural selection: Repetition of similar traits in similar environments in different animal species

86
Q

Building the evidence: Fossils

A

A fossil is any mineralized evidence of a once-living organism

This includes body parts, casts, molds, footprints, track ways, and feeding traces

The vast majority of fossils are found in sedimentary rocks

87
Q

Fossilization

A

Most organisms will NOT end up being preserved after death

The fossil record represents only a tiny fraction of all the individual organisms that inhabited the Earth

Process of fossilization is very specific; need to have right type of soil, water, all of these steps

88
Q

Process of Fossilization

A

Animal dies on lakeshore

After soft tissue decays, only skeleton left

Water level rises, sediment covers bones

Bones fossilize in thick layer of sediment at bottom of lake, while sediments continue to be deposited as layers

Lake dries and other geologic processes occur. Volcanic eruption spews ash over region, providing more layers. Fossil now embedded in geologic stratum

Erosion exposes deep strata in a geologic column, revealing the fossilized skeleton

89
Q

Superposition

A

Older layers of sediment are covered by younger layers, so that in a sedimentary sequence the youngest layer is at the top

90
Q

Succession

A

Different layers contain particular types of fossilized organisms

These fossils replace each other in a specific and predictable temporal order that can be identified and dated
-We can see when new forms arise based on the layer their fossils are in

91
Q

Transitional forms

A

Formerly called “missing links” they represent organisms with intermediate characteristics between other major groups
-Important in determining relationships between organisms

There are thousands of examples of intermediate forms linking virtually all groups of organisms

Fossil records thus capture gradual changes in organisms over time

92
Q

Transitional Examples

A

Archeopteryx: Dinosaur with feathers, dino turning into a bird

Tiktaalik transition from water to land

The methods used to find fossils to fill in gaps is actually very rigorous

Limbed animals thought to come from fish; the black was the initial hypothesis; Tiktaalik was the missing link

93
Q

Transitional example: Tiktaalik

A

Finding transitional fossils is not necessarily random

To find Tiktaalik, scientists used existing fossils to determine when in the past limbs SHOULD HAVE evolved

They then searched for where on earth the right kind of rock existed from that time period

When they dug in that location, they found the fossil they were looking for

94
Q

What is the basic idea behind natural selection?

a) Differential survival when resources are limited
b) Extinction when resources are limited
c) Inheritance of acquired traits
d) Sexual reproduction

A

a) Differential survival when resources are limited

95
Q

Darwin’s Challenges:

A

Evolution of complex traits: Structures with multiple intricate parts, like eyes
-Hard for him to explain how complex structures could evolve via a slow process

Traits and structures of seemingly little importance - nipples on male animals

Elaborate traits that offer no fitness advantage

The source of variation
-Knew that populations vary and knew that the variation is heritable, but he did not know WHY

We now have answers to all of these problems, as we will see in later lectures

96
Q

Darwinian Genetics

A

The mode of inheritance was also a huge problem for Darwin - he knew traits were transmitted from parents to offspring, but he didn’t know how

Darwin speculated that characteristics of the parents were blended - like mixing paint - as they passed to the offspring
-Got this WRONG

But if that was true, how could a single fortunate change be spread through a species?

After Darwin’s death, alternative evolutionary mechanisms were proposed, none of which were ultimately supported
-The discovery of DNA is what helped in understanding the variation within species

97
Q

What is Evolution?

A

Evolution is change over time, the change in allele frequencies (genetic variants) over time

Darwin did NOT initially describe evolution as changes in allele frequencies. He conceptualized it as changes in phenotype - the outward appearance of an organism
-We now know that phenotypes are determined by underlying alleles

98
Q

Critical reception of the Origin

A

Book sold out immediately and was widely debated

Ideas were (surprisingly to Darwin) generally widely accepted among scientists

Detractors claimed ideas were too dangerous for “ordinary” readers

Anglican church was divided, but natural selection was viewed as a conception of a deity by many

99
Q

Evolution in the US: The Scopes Trial (1925)

A

Teaching human evolution was banned in Tennessee

Trial pitted Christian Modernists against Fundamentalists

Scopes ultimately found guilty, but public opinion is generally thought to have turned against Fundamentalists

In 1968, the Supreme Court ruled that bans on teaching evolution in public schools violate the Establishment Clause of the First Amendment by promoting a specific religion

100
Q

Challenges to Evolution: Intelligent Design

A

Michale behe and collaborators at the Discovery Institute proposed the idea that some structures are too complex at the biochemical elvel to be adequately explained as the result of evolution

A creator therefore must have been involved in the production of such structures

This group pushed to have Intelligent Design taught in biology classrooms

Promotes the idea that there is some deity behind natural selection; not a testable and falsifiable hypothesis

101
Q

Dover School District Trial

A

Whether Intelligent Design could be taught in High School classrooms

In Kitzmiller vs. Dover Area School District Trial, Judge John E. Jones III said:
“The overwhelming evidence at trial established that Intelligent Design is a religious view, a mere re-labeling of creationism, and not a scientific theory.”

102
Q

Evolution today

A

No serious legal challenges to teaching evolution in public schools since Kitzmiller v Dover

Large percentages of Americans report feeling “unsure” about their belief in evolution

Rejection of science and fact- and evidence-based decision making at all levels of society

103
Q

Which of these are central components of evolutionary theory?

a) Species change over time
b) Species share common ancestors
c) Species are well-suited to their environments
d) All of the above

A

d) All of the above

104
Q

What were Darwin’s two key insights about evolution in the Origin?

A

1) Evolution by natural selection

2) Common ancestry

105
Q

What are the four components of natural selection we discussed in class?

A

1) Phenotypes vary in population
2) More offspring produced than can survive
3) Phenotypes are heritable
4) Some phenotypes are more likely to survive

106
Q

What is artificial selection?

A

Humans breed certain varieties for specific traits; very similar to natural selection, just different method of obtaining results

107
Q

Is natural selection variational or transformational? Why?

A

Variational

Variational is the method proposed by Darwin: Occurs via extinction, slowly over time, only those that suit environment will survive

108
Q

Which of these is NOT a testable hypothesis?

a) Species are designed to be suited to their environments by a “watchmaker”
b) Most geologic change on earth is caused by catastrophic events
c) Species do not change over long periods of tie
d) Species are able to acquire novel adaptations during their lifetimes

A

a) Species are designed to be suited to their environments by a “watchmaker”

109
Q

Which is correct about Darwin’s views on natural and artificial selection?

a) He viewed them as fundamentally different processes
b) He viewed them as essentially the same process, with only the selective agent differing
c) He believed only artificial selection could produce new species
d) He thought natural and artificial selection could produce new varieties, but not new species

A

b) He viewed them as essentially the same process, with only the selective agent differing

110
Q

Under Darwin’s hypothesis of a common ancestry of all living things, we would expect to observe:

a) Hierarchical clustering and a branching tree of life among all living things, wherein species that appear to be more similar are more likely to be closely related
b) Species independently progressing from simple to more complex over time
c) Random and unpredictable relationships among species
d) Hierarchical clustering among varieties, but no predictable clustering among species

A

a) Hierarchical clustering and a branching tree of life among all living things, wherein species that appear to be more similar are more likely to be closely related

111
Q

Methodological naturalism set the stage for the modern scientific method by:

a) Stating that the earth changed gradually over time
b) Demonstrating that species are adapted to their environments
c) Seeking explanations for the natural world driven by physical laws
d) Suggesting that animals struggle for existence

A

c) Seeking explanations for the natural world driven by physical laws

112
Q

Which of these is NOT a component of natural selection as described by Darwin?

a) Organisms reproduce via sexual reproduction
b) Survival and reproduction are non random: individuals carrying specific variations survive and reproduce the most
c) Individuals within species are variable
d) Individuals pass their variants on to their offspring

A

a) Organisms reproduce via sexual reproduction

113
Q

Which of these was a challenge for Darwin to explain under his theory of evolution?

a) All of these were challenges for Darwin to explain
b) Structures of seemingly no importance
c) Complex structures such as eyes
d) Elaborate traits with no fitness advantage

A

a) All of these were challenges for Darwin to explain

114
Q

A consequence of Malthus’s ideas that populations outstrip their available resources is that:

a) Individuals will acquire heritable characteristics that help their offspring survive
b) The individuals best able to monopolize resources will survive
c) Individuals vary within a population
d) Individuals resemble their parents

A

b) The individuals best able to monopolize resources will survive

115
Q

What is the definition of evolution?

a) Acquisition of beneficial characteristics
b) Change in allele frequencies over time
c) Resemblance of offspring and parents
d) Survival of the fittest

A

b) Change in allele frequencies over time

116
Q

Transitional forms are:

a) Species with intermediate characteristics between major groups
b) Species exceptionally adapted to their environments
c) Ecological analogues to other species
d) Groups that radiated on islands

A

a) Species with intermediate characteristics between major groups

117
Q

Which of these assertions is Darwinian and not Lamarckian?

a) An individual that acquired new characteristics in its lifetime is able to transmit them to its offspring
b) There is no extinction
c) Individuals better suited to their environment reproduce more than others and pass beneficial characteristics to their offspring
d) Individual organisms evolve because they need to survive or use new resources

A

c) Individuals better suited to their environment reproduce more than others and pass beneficial characteristics to their offspring

Evolution (15 decks)

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