evolution chapter 13 “a change over time” ft3fu2xogo ft3fu2xogo
TRANSCRIPT
![Page 1: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/1.jpg)
EvolutionChapter 13
“A change over time”
![Page 2: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/2.jpg)
http://www.youtube.com/watch?v=-FT3FU2XOgo
http://www.hulu.com/watch/403434#details=expand
![Page 3: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/3.jpg)
The Theory of Evolution Evolution literally means to change over
time. A theory is a well supported, testable
explanation that observes observations from the natural world
![Page 4: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/4.jpg)
Questions that evolution attempts to answer. How do species adapt to changes in the
environment? How do new species develop?
![Page 5: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/5.jpg)
Charles Darwin
1809-1882 Studied to be a doctor
and a minister 1831 sailed around the
world as a naturalist on the HMS Beagle
![Page 6: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/6.jpg)
HMS Beagle
![Page 7: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/7.jpg)
Darwin’s Voyage
![Page 8: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/8.jpg)
Galapagos Islands
![Page 9: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/9.jpg)
Galapagos Islands
![Page 10: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/10.jpg)
![Page 11: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/11.jpg)
![Page 12: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/12.jpg)
15-2 Darwin’s Influences
![Page 13: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/13.jpg)
James Hutton Geologist Proposed that the earth was
millions of years old based on geologic evidence
![Page 14: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/14.jpg)
Sir Charles Lyell
Geologist Proposed that geologic
changes occur slowly over long periods of time.
Darwin read his book, Principles of Geology, on the Beagle
![Page 15: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/15.jpg)
Jean Baptiste Lamarck
French Naturalist
Published his ideas on evolution in 1809 in Philosophie zoologique
![Page 16: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/16.jpg)
Lamarck’s Hypothesis
Organisms Strive for Perfection – all individuals are trying to better themselves
![Page 17: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/17.jpg)
Lamarck’s HypothesisUse and Disuse –
If an individual uses a trait it will be more useful
If an individual does not use a trait it will decrease in usefulness
![Page 18: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/18.jpg)
Lamarck’s Hypothesis
Inheritance of Acquired characteristics
![Page 19: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/19.jpg)
Analyzing Lamarck’s Hypothesis There is no evidence to suggest that plants
and animals are trying to improve themselves
![Page 20: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/20.jpg)
Analyzing Lamarck’s Hypothesis Use and disuse do not change all
characteristics Stretching will not make you taller Reading will not make your eyesight better
![Page 21: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/21.jpg)
Analyzing Lamarck’s Hypothesis Acquired characteristics are not inherited
A mouse that loses its tail will still produce offspring with tails
![Page 22: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/22.jpg)
Erasmus Darwin
Charles Darwin’s Grandfather
Physician and Scientist
'All vegetables and animals now living were originally derived from the smallest microscopic ones.'
![Page 23: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/23.jpg)
Thomas Malthus –
Economist Human Population would be
limited Starvation War (Competition) Disease
![Page 24: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/24.jpg)
15-3 Darwin Presents His Case
![Page 25: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/25.jpg)
Alfred Wallace Developed his own theory
of Natural Selection Contacted Darwin This caused Darwin to
finally publish his theory with Wallace
![Page 26: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/26.jpg)
On Origins of Species After publishing with
Wallace, Darwin submitted all of his ideas in a book titled On Origin of Species, By Means of Natural Selection in 1858
![Page 27: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/27.jpg)
Artificial Selection Darwin was influenced to believe change
was possible because of the humans selecting for traits in plants and animals.
![Page 28: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/28.jpg)
![Page 29: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/29.jpg)
Darwin’s Theory
Evolution “Change” is driven by natural selection
![Page 30: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/30.jpg)
Summary of Darwin’s Theory
![Page 31: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/31.jpg)
Variation There are differences within a population
Mutation and Sexual Reproduction
![Page 32: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/32.jpg)
Competition for resources Not all offspring will survive
Starvation Overcrowding Predation
![Page 33: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/33.jpg)
Fitness Some of the variants will have an
advantage over the others, they will survive and produce more offspring
![Page 34: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/34.jpg)
Reproduction and Inheritance These advantages will be passed on to the
next generations
![Page 35: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/35.jpg)
Descent with Modification Species alive today are descended with
modification from ancestral species
![Page 36: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/36.jpg)
Tree of Life All species are connected on a single tree
of life
![Page 37: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/37.jpg)
Modern Theory Mendel’s discoveries in genetics explained
a great deal in evolution
![Page 38: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/38.jpg)
Evidence for Evolution Fossil Record Anatomy Development Molecular Evidence
![Page 39: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/39.jpg)
Fossil Record Since most of the “ancestor” species are
extinct, fossils are the only evidence that can be examined.
Intermediate “missing link” fossils are very informative
![Page 40: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/40.jpg)
Archaeopterix
A fossil of a bird like creature
Has feathers, teeth and claws in its wings
![Page 41: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/41.jpg)
Whale Ancestors http://www.youtube.com/watch?
v=lx079oEgKKs
![Page 42: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/42.jpg)
Anatomy
Structures similarities in body structure indicates organisms are related
![Page 43: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/43.jpg)
Homologous StructuresStructures that have common function and design (ancestry)
![Page 44: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/44.jpg)
![Page 45: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/45.jpg)
Vestigial Organs
Structures that have reduced size and or function
http://www.youtube.com/watch?v=pbc7ee9u1JE
![Page 46: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/46.jpg)
![Page 47: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/47.jpg)
![Page 48: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/48.jpg)
![Page 49: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/49.jpg)
![Page 50: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/50.jpg)
Developmental Evidence Similarities in embryonic development are
interpreted to mean closer relationships.
![Page 51: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/51.jpg)
Developmental Evidence Similarities in embryonic development are
interpreted to mean closer relationships.
![Page 52: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/52.jpg)
Molecular Evidence
Organisms are considered to be more closely related if
DNA sequences in genes are more similar
Amino acid sequences in proteins is more similar
![Page 53: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/53.jpg)
Molecular Evidence
Organisms are considered to be more closely related if
DNA sequences in genes are more similar
Amino acid sequences in proteins is more similar
![Page 54: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/54.jpg)
Strengths of Darwin’s Theory
Many discoveries in Physics, Geology and Biology have supported and expanded Darwin’s ideas
![Page 55: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/55.jpg)
Strengths of Darwin’s Theory
Many discoveries in Physics, Geology and Biology have supported and expanded Darwin’s ideas
![Page 56: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/56.jpg)
Weaknesses of Darwin’s Theory Researchers still debate how new species
arise and how they become extinct. The origin of life is still very uncertain
![Page 57: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/57.jpg)
Evolution of Populations
Chapter 14
![Page 58: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/58.jpg)
Genes and Variation Variation – differences between individuals
of a species Produced by two processes
Mutation – random changes in DNA Sexual Reproduction- combining genes from two
gametes
![Page 59: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/59.jpg)
Single Gene Traits Several traits are controlled by a single
gene and are either dominant or recessive.
![Page 60: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/60.jpg)
Polygenic Traits Poly-genic means “many genes” Most traits are controlled by several genes
and can show up in many different forms.
![Page 61: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/61.jpg)
Normal Curve Most individuals are intermediate, extremes
are less common
![Page 62: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/62.jpg)
Microevolution Micro – small Microevolution is change within a species Gene Pool – all of the genes in a population Allele Frequency – how many times a
certain allele shows up in the population
![Page 63: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/63.jpg)
Microevolution
Any change in Allele frequency in a population is considered microevolution
![Page 64: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/64.jpg)
English Peppered MothThe English Peppered MothThe moth was usually white with dark spotsDuring the Industrial Revolution (1850’s) soot
covered many of the white barked treesMore and more dark colored moths appeared
at the same timeKettlewell’s experiments suggested this was
due to natural selection
![Page 65: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/65.jpg)
English Peppered MothThe English Peppered MothThe moth was usually white with dark spotsDuring the Industrial Revolution (1850’s) soot
covered many of the white barked treesMore and more dark colored moths appeared
at the same timeKettlewell’s experiments suggested this was
due to natural selection
![Page 66: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/66.jpg)
![Page 67: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/67.jpg)
Microevolution in Humans
Sickle Cell Anemia is a recessive (hh) disease found mainly in Africa
A carrier (Hh) for the disease has resistance to malaria
![Page 68: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/68.jpg)
Delta 32 Mutation Delta 32 mutation occurs in 10-15% of
whites of European descent This mutation gave resistance to the plague Most of the people without this allele died of
the plague causing the allele frequency to rise
The mutation also gives resistance to HIV infection
![Page 69: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/69.jpg)
![Page 70: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/70.jpg)
![Page 71: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/71.jpg)
![Page 72: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/72.jpg)
![Page 73: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/73.jpg)
![Page 74: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/74.jpg)
![Page 75: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/75.jpg)
Selection Selection can be one of 3 forms
Directional Stabilizing Disruptive
![Page 76: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/76.jpg)
![Page 77: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/77.jpg)
Stabilizing Selection
Both Extremes are selected against The population is stabilized
![Page 78: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/78.jpg)
Directional Selection One of the extremes is selected against,
the population shifts away
![Page 79: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/79.jpg)
Disruptive Selection The most common variation is selected
against spitting the species two groups
![Page 80: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/80.jpg)
Genetic Drift In small population individuals may pass on
more genes by chance. This is called genetic drift.
Large populations are not affected by genetic drift
![Page 81: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/81.jpg)
Genetic Drift
Population 18
9 Heads
9 Tails
![Page 82: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/82.jpg)
![Page 83: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/83.jpg)
Population 18
6 Heads
12 Tails
![Page 84: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/84.jpg)
Can a species stop evolving?
Hardy Weinberg equilibruim
in order for evolution of a species not to occur
(all allele frequencies stay the same)
5 evolutionary forces must not act
![Page 85: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/85.jpg)
Hardy Weinberg Equilibrium
Populations do not evolve if there is
Random Mating
no movement into or out of the population
no genetic drift, large population
no natural selection
no mutation
![Page 86: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/86.jpg)
16-3 The Process of Speciation Speciation –the production of a new
species Species – a group of individuals that
reproduce in nature and produce fertile offspring
Isolation – the factor that prevents the new species from reproducing with the ancestral species
![Page 87: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/87.jpg)
Behavioral Isolation Mating songs or rituals are different, so the
two species don’t interbreed
![Page 88: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/88.jpg)
Behavioral Isolation Groups are not attracted to each other for
mating
![Page 89: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/89.jpg)
Geographic Isolation Groups are physically separated and no
longer interbreed
![Page 90: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/90.jpg)
Temporal Isolation Groups reproduce at different times of day
or year
![Page 91: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/91.jpg)
Mechanical Isolation Structural differences prevent mating
between individuals of different groups
![Page 92: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/92.jpg)
Ecological Isolation Groups are adapted to different habitats,
hybrids aren’t adapted well to either
![Page 93: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/93.jpg)
Reproductive Failure Mating between groups fail to produce
fertile offspring
![Page 94: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/94.jpg)
Speciation Continued Once populations are isolated, different
pressures select different traits When the populations will no longer
interbreed, new species have been formed
![Page 95: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/95.jpg)
Natural Selection - 2 forms Ecological Selection – better suited to
survive in the environment Sexual Selection –
Males compete for access to females Females select males with “good gene” markers
![Page 96: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/96.jpg)
Sexual Dimorphism Dimorphism di-morph-ism
Two forms Males are usually larger Males would have ornaments (antlers, manes,
colors)
![Page 97: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/97.jpg)
![Page 98: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/98.jpg)
Patterns of Evolution
![Page 99: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/99.jpg)
Macro Evolution
Macro – Large
Idea that species can split to form new species
All life forms are related through a common ancestor
![Page 100: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/100.jpg)
Divergent Evolution
Similar species develop different adaptations to different environments
![Page 101: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/101.jpg)
Convergent Evolution
Two species develop similar adaptations to the same environment.
![Page 102: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/102.jpg)
Coevolution Two or more species adapting to each
other
![Page 103: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/103.jpg)
Rate of Evolution Slow and Steady or in Spurts?
Gradualism – the idea that small changes build up slowly over time to produce large changes.
Expectations – many intermediate “missing link” fossils
![Page 104: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/104.jpg)
![Page 105: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/105.jpg)
Punctuated Equilibrium
The idea that populations go through periods of stability followed by short periods of rapid change.
Expectations – fewer intermediate fossils
![Page 106: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/106.jpg)
![Page 107: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/107.jpg)
Endosymbiont Theory
Endo –inside Symbiont – symbiotic “mutualistic”
relationship
![Page 108: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/108.jpg)
Endosymbiont Theory
This theory suggests that mitochondria and chloroplasts were once independent living organisms
These organisms were “eaten” by larger cells, but remained alive
![Page 109: Evolution Chapter 13 “A change over time” FT3FU2XOgo FT3FU2XOgo](https://reader038.vdocument.in/reader038/viewer/2022103004/56649cdb5503460f949a4fe3/html5/thumbnails/109.jpg)
Endosymbiont Theory
Evidence for endosymbiosis Each mitochondrian has its own circular chromosome of DNA Very similar to a bacteria Reproduce on its own Ribosomes are very similar to bacterial ribosomes