Selection - Seattle Central College
... • Frequency: Percentage of states that are of a given type – If 75 of 100 humans have blue eyes, then the blue eye phenotype occurs at a frequency of ...
... • Frequency: Percentage of states that are of a given type – If 75 of 100 humans have blue eyes, then the blue eye phenotype occurs at a frequency of ...
Ch 16 Summary
... of evolutionary change. In small populations, alleles can become more or less common simply by chance. This kind of change in allele frequency is called genetic drift. It occurs when individuals with a particular allele leave more descendants than other individuals, just by chance. Over time, this c ...
... of evolutionary change. In small populations, alleles can become more or less common simply by chance. This kind of change in allele frequency is called genetic drift. It occurs when individuals with a particular allele leave more descendants than other individuals, just by chance. Over time, this c ...
Mechanisms of Evolution
... Evolution occurs by Natural Selection. Natural selection states: 1. More organisms are born than can survive. 2. Resources are limited, so there is competition for those resources. 3. Organisms with favorable adaptations (characteristics) to a particular environment survive and leave more offspring ...
... Evolution occurs by Natural Selection. Natural selection states: 1. More organisms are born than can survive. 2. Resources are limited, so there is competition for those resources. 3. Organisms with favorable adaptations (characteristics) to a particular environment survive and leave more offspring ...
The overviews in Chapter 1: 1. How natural selection shapes
... have much more food available, and leave more genes in the next generation. If the reproductive success of the individuals with that allele was just 1% more than “normal” snakes, in 10,000 years the coastal population would be composed almost entirely of slugs-are-OK snakes. ...
... have much more food available, and leave more genes in the next generation. If the reproductive success of the individuals with that allele was just 1% more than “normal” snakes, in 10,000 years the coastal population would be composed almost entirely of slugs-are-OK snakes. ...
Today:
... It emphasizes the genetic variation within populations and acknowledges the importance of QUANTITATIVE CHARACTERS. ...
... It emphasizes the genetic variation within populations and acknowledges the importance of QUANTITATIVE CHARACTERS. ...
Genetic drift
... 7. True or False. If the statement is false explain why. Most natural populations are in equilibrium. False; most are evolving Mutations arise in response to changes in the environment. False, mutations arise by random chance Genetic drift has a larger impact on small populations.True Natural select ...
... 7. True or False. If the statement is false explain why. Most natural populations are in equilibrium. False; most are evolving Mutations arise in response to changes in the environment. False, mutations arise by random chance Genetic drift has a larger impact on small populations.True Natural select ...
Evolution of Populations
... fitted” (have highest fitness) than both ends Peccaries are consuming the low-spine number plants, and the insects are killing the high-spine-number plants. As these gene combinations are removed from the cactus gene pool, there is less and less variety possible in subsequent generations. ...
... fitted” (have highest fitness) than both ends Peccaries are consuming the low-spine number plants, and the insects are killing the high-spine-number plants. As these gene combinations are removed from the cactus gene pool, there is less and less variety possible in subsequent generations. ...
Models of Selection
... How long would it take for 95% of the alleles to be A if A is initially present in 5% of the population and if the selection coefficient favoring allele A is... s = 0.1? ...
... How long would it take for 95% of the alleles to be A if A is initially present in 5% of the population and if the selection coefficient favoring allele A is... s = 0.1? ...
Unit 3
... about 65 million years ago AND four other cataclysmic events that wiped out almost all organisms, plant and animal, during the 3.8 billion years of life on Earth. Yet in his book The Origin of Species, Darwin suggests: “Evolution and extinction go hand-in-hand” and “...the manner in which single spe ...
... about 65 million years ago AND four other cataclysmic events that wiped out almost all organisms, plant and animal, during the 3.8 billion years of life on Earth. Yet in his book The Origin of Species, Darwin suggests: “Evolution and extinction go hand-in-hand” and “...the manner in which single spe ...
Slide 1
... ("Green beard model"). Perhaps, several of these mechanisms contribute to evolution of cooperation in nature (J. Evol. Biol. 20, 415-432, 2007). ...
... ("Green beard model"). Perhaps, several of these mechanisms contribute to evolution of cooperation in nature (J. Evol. Biol. 20, 415-432, 2007). ...
Genetical theory of natural selection
... Fitness depends not only on reproductive success, especially when species reproduce sexually and have more than one reproductive event Age of reproduction Selection during sexual reproduction Phenotype and fitness Relationship described by modes of selection Directional Stabilizing (norm ...
... Fitness depends not only on reproductive success, especially when species reproduce sexually and have more than one reproductive event Age of reproduction Selection during sexual reproduction Phenotype and fitness Relationship described by modes of selection Directional Stabilizing (norm ...
Hardy-Weinberg Principle • Population genetics
... variation must exist among individuals variation must result in differences in numbers of viable offspring produced variation must be genetically inherited natural selection is a process, and evolution is an outcome ...
... variation must exist among individuals variation must result in differences in numbers of viable offspring produced variation must be genetically inherited natural selection is a process, and evolution is an outcome ...
Evolution at multiple loci
... Requirements of natural selection • Individuals vary • Some of that variation is genetic • More offspring are produced that can survive (reproduce) • Survival (reproduction) not random ...
... Requirements of natural selection • Individuals vary • Some of that variation is genetic • More offspring are produced that can survive (reproduce) • Survival (reproduction) not random ...
What Darwin Never Knew
... Mutations can also be caused by environmental factors, such as radiation and certain chemicals. These factors are called mutagens. ...
... Mutations can also be caused by environmental factors, such as radiation and certain chemicals. These factors are called mutagens. ...
Unit 4 Evolution Study Guide There are five driving forces of
... Directional: members at one end of a spectrum are selected for, and population shifts toward that end; bell curve will move to the right or the left Stabilizing: selection for the middle or average trait and against either extreme; reduces variation in the population; bell curve becomes more narrow ...
... Directional: members at one end of a spectrum are selected for, and population shifts toward that end; bell curve will move to the right or the left Stabilizing: selection for the middle or average trait and against either extreme; reduces variation in the population; bell curve becomes more narrow ...
How populations evolve
... Small populations may not start out with a lot of variation If they are isolated from other populations of the same species, their allele frequencies can change ...
... Small populations may not start out with a lot of variation If they are isolated from other populations of the same species, their allele frequencies can change ...
evolution
... hiking boots for sneakers. The second hiker says, “What are you doing?! You’ll never outrun that bear, sneakers or no sneakers!” The first hiker replies, “I don’t have to outrun the bear, I just have to outrun you.” The joke is about the difference between absolute and relative fitness, and the impo ...
... hiking boots for sneakers. The second hiker says, “What are you doing?! You’ll never outrun that bear, sneakers or no sneakers!” The first hiker replies, “I don’t have to outrun the bear, I just have to outrun you.” The joke is about the difference between absolute and relative fitness, and the impo ...
File
... Students often suggest that extant species have evolved from other extant species, e.g. humans have evolved from chimps, rather than from a common ancestor. Some students will have a view of evolution based on faith – try to help them distinguish between science and religion as two separate systems. ...
... Students often suggest that extant species have evolved from other extant species, e.g. humans have evolved from chimps, rather than from a common ancestor. Some students will have a view of evolution based on faith – try to help them distinguish between science and religion as two separate systems. ...
Evidence from the gnarly New Zealand snails for and against the red
... 12. What is run-away sexual selection? How does it generate linkage disequilibrium and genetic correlations? How would you test for the existence of genetic correlations generated by sexual selection? Do you think the selection experiments on stalk-eyed flies showed the expected correlated response ...
... 12. What is run-away sexual selection? How does it generate linkage disequilibrium and genetic correlations? How would you test for the existence of genetic correlations generated by sexual selection? Do you think the selection experiments on stalk-eyed flies showed the expected correlated response ...
Evidence from the gnarly New Zealand snails for and against the red
... 14. What happens to additive genetic variation under run-away sexual selection? What models, if any, can explain the maintenance of additive genetic variation under strong female choice for male traits? Describe the Hamilton and Zuk hypothesis. What is meant by condition-dependent mate choice? 15. ...
... 14. What happens to additive genetic variation under run-away sexual selection? What models, if any, can explain the maintenance of additive genetic variation under strong female choice for male traits? Describe the Hamilton and Zuk hypothesis. What is meant by condition-dependent mate choice? 15. ...
Genomic selection is especially useful for
... 1930s-Molecular Biology begins. 1965-Margaret Dayhoff's Atlas of Protein Sequences 1970-Sequencing techniques by Fredirick Sanger ...
... 1930s-Molecular Biology begins. 1965-Margaret Dayhoff's Atlas of Protein Sequences 1970-Sequencing techniques by Fredirick Sanger ...
Group selection
Group selection is a proposed mechanism of evolution in which natural selection is imagined to act at the level of the group, instead of at the more conventional level of the individual.Early authors such as V. C. Wynne-Edwards and Konrad Lorenz argued that the behavior of animals could affect their survival and reproduction as groups.From the mid 1960s, evolutionary biologists such as John Maynard Smith argued that natural selection acted primarily at the level of the individual. They argued on the basis of mathematical models that individuals would not altruistically sacrifice fitness for the sake of a group. They persuaded the majority of biologists that group selection did not occur, other than in special situations such as the haplodiploid social insects like honeybees (in the Hymenoptera), where kin selection was possible.In 1994 David Sloan Wilson and Elliott Sober argued for multi-level selection, including group selection, on the grounds that groups, like individuals, could compete. In 2010 three authors including E. O. Wilson, known for his work on ants, again revisited the arguments for group selection, provoking a strong rebuttal from a large group of evolutionary biologists. As of yet, there is no clear consensus among biologists regarding the importance of group selection.