Evolution In The Past Flashcards

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1
Q

What is Mutation?

A

Mutation is anything that disrupts your normal genes/pigments (A change in the genotype/DNA of an organism)

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2
Q

Effects of Mutation

A
  • Mutation create a continual supply of new genetic information
  • Has an immediate and direct effect on individuals
  • Influences/changes the genes of further generations
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3
Q

Why Do Organisms Mutate?

A

Organisms mutate to survive/adapt better in their environment

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4
Q

Mutation Types

A
  • Neutral
  • Harmful
  • Beneficial
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5
Q

Neutral Mutation

A

Provides no benefit or harm

e.x occurrence of freckles due to the sun

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6
Q

Harmful Mutation

A

Reduce the reproductive success

e.x genetic disorder

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7
Q

Beneficial Mutation

A

Changes the individual’s phenotype to provide an advantage

(e.x The Rock Pocket Mouse: the furs of the mouses mutate overtime to blend in w/the background. Their fur changes/mutates depending on if the volcano erupts. It is a beneficial mutation because the changes helps them blend in with the background and hide from predators)

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8
Q

Advantages of Selective Breeding/ Artificial Selection

A
  • Provides variation in but not due to environmental pressures
  • We are able to control what and who we want to mate with
  • Increase the population
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9
Q

Example of Artificial Selection

A
  • Dogs and cats

- Because tigers are going extinct, scientists are breeding the tigers with the lions to save the tiger genes

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10
Q

Limitations of Selective Breeding/ Artificial Selection

A
  • Limit the genetic pool. AKA no genetic variety
  • Will be breeding siblings together
  • Population easily wiped out by diseases etc. because everyone in the pool has the same/similar genes
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11
Q

2 of Lamarck’s Theory: Adaption: Why do species change over time?

A
  1. Use and Disuse

2. Inheritance of Acquired Characteristics

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12
Q

Use and Disuse

A

Structures that were used often became stronger and larger than those that were not used became smaller and weaker

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13
Q

Example of Use and Disuse

A

Tailbones in humans: we don’t have a tail so there is no use of a tailbone

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14
Q

Inheritance of Acquired Characterstics

A

Individuals could pass on advantageous characteristics that they had acquired during their lives onto their offsprings

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15
Q

Example of Inheritance of Acquired Characterstics

A

If the climate cooled, the animals might respond by growing a thicker coat of hair and would pass on this acquired characteristics to their offsprings

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16
Q

Lamarck’s Giraffes

A

Example of use and adaption:

  • The giraffe had an originally short-necked ancestor, but the giraffe eats leaves that grows high on trees. Because the giraffe constantly used it’s neck to reach for leaves that are high, the neck stretches overtime until it became progressively longer
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17
Q

Flaws in Lamarck’s Theory

A

Not all of the traits from the parents can be passed onto their future generation
(e.x. You can stretch your muscles but that does not change the DNA that will be inherited; only a mutation will do that)

18
Q

Ideas for Further Research Concluded from Lamarck

A
  1. All species evolve over time
  2. A specie evolves in response to its environment and becomes better adapted
  3. Changes are passed on from generation to generation
19
Q

Who was Charles Darwin?

A
  • English Naturalist
  • The Origin of Species
  • Father of Evolution
  • Voyage on the Beagle
    when he was 22 to find the evidence to propose a hypothesis about how life changes over time
20
Q

What is Natural Variation

A

Differences among individuals of a species

21
Q

What is Artificial Selection

A

When nature provides the variation among different organisms, and humans select those variation they find useful and continues

22
Q

What is Artificial Selection?

A

When nature provides the variation among different organisms, and humans select those variation they find useful and continues to breed them

23
Q

What Is The Main Force Behind Evolution?

A

Natural Selection

24
Q

2 Main Drives for Evolution

A
  1. The struggle for existence

2. Survival of the fittest

25
Q

The Struggle for Existence

A

Member of each species competing for food, shelter and other life necessities

26
Q

Survival of the Fittest

A

Some individuals are better suited for the environment than others

27
Q

What is Natural Selection?

A

Natural Selection results in changes in inherited characteristics of a population due to environmental pressures. These changes increases a species FITNESS in its environment and their ADAPTABILITY to an environment

28
Q

Which 4 Things Are Needed for Natural Selection to Work? (Darwin’s Summary0

A
  1. Genetic Variation
  2. Overpopulation of Offsprings
  3. Struggle for Existence
  4. Differential Survival and Reproduction
29
Q

Genetic Variation

A

Individuals in nature differ from one another. In order for natural selection to work, ONLY THE ADVANTAGEOUS characteristics can be passed down to the next generation

30
Q

Overpopulation of Offsprings

A

Individuals intend to produce more offspring than can survive, those who do not survive do not reproduce
(e.x. hummingbirds produce dozens of offsprings but only 1 or 2 of them will survive)

31
Q

Struggle for Existence

A

Because of the large amount of offsprings produced, there is a lot of competition for food, space and mates (RELATED TO differential survival and reproduction)

32
Q

Differential Survival and Reproduction

A
  • Each organism is unique, each has advantages and disadvantages in the struggle for existence.
  • Only the individuals best suited for the environment survive and pass on their advantageous traits by reproducing.
    e. x Hummingbirds compete for nectars. Natural selection will favour individuals who are more efficient in getting the nectars. Natural selection will change the characteristics of the hummingbirds, making them more adapted to getting nectars.
    e. x Hummingbirds have long beaks and short beaks, but the environment is suited for the birds with longer beaks. Therefore the population with short beaks die and eventually the only humming birds left in that environment are the ones with long beaks
33
Q

Results That Came From The Idea of Natural Selection

A
  1. Descents w/modifications
    - The changes in the species occurs over a long period of time. Little changes occur in each generation, overtime these little changes builds up to enormous changes.
  2. Common Descent
    - All organisms on earth came from one common descent
34
Q

Evidence of Evolution and Darwin’s Theory (5)

A
  1. Fossil Record
  2. Geographic Distribution of Living Things
  3. Homologous Body Structures
  4. Vestigial Organs
  5. Similarities in Early Development
35
Q

Fossil Record

A
  • Darwin collected fossils during his journey
  • Those fossils are compared to organisms that are still alive today. We can see minor changes between the two, which indicates that the organism is evolving
  • But some fossils looked completely unlike any creature he had ever seen
36
Q

Geographic Distribution of Living Things

A
  • Similar environments have similar types of organisms
  • All the organisms in the diagram on the right are the same species but they look different because they live in different parts of the world. Therefore they have to change and adapt to the environment they live in.
37
Q

Homologous Body Strucutres

A
  • Structures that have different mature forms in different organisms, but develop from the same embryonic tissue
  • They may look different in different species but they perform the same function
38
Q

Example of Homologous body strucutre

A

Arm in a human and a fine in a dolphin

39
Q

Vestigial Organs

A

Organs that serves no useful function in an organism

40
Q

Examples of Vestigial Organs

A

In humans, the appendix, wisdom teeth

41
Q

Similarities in Early Development (Embryology)

A
  • Embryology is the study of tissue before it forms into an organism
  • The study shows that we all descend from one common ancestor