Biological Foundations of Sexuality
... Orientation: A Theory of Homosexuality-Heterosexuality,” Ellis, L. and Ames, M.A. Psychological Bulletin, 101:233-258 (1987). Sexual orientation in all mammals is primarily determined by the degree to which the nervous system is exposed to testosterone and certain other sex hormones during gestation ...
... Orientation: A Theory of Homosexuality-Heterosexuality,” Ellis, L. and Ames, M.A. Psychological Bulletin, 101:233-258 (1987). Sexual orientation in all mammals is primarily determined by the degree to which the nervous system is exposed to testosterone and certain other sex hormones during gestation ...
By Alfred Russel Wallace, LL. D., DCL, FRS, etc. In two
... who maintained that Nature is in a "state of continual Bnx and movement," and that she can do all "except create matter or destroy it." These views as modified by Lamarck and other writers obtained considerable weight with the best thiukers, but not before Darwin had anyone been able to show how" th ...
... who maintained that Nature is in a "state of continual Bnx and movement," and that she can do all "except create matter or destroy it." These views as modified by Lamarck and other writers obtained considerable weight with the best thiukers, but not before Darwin had anyone been able to show how" th ...
Human Evolution - Santa Fe Institute
... demise of many leaderless hominid social formations, and the consolidation of new hominid social relations based on novel forms of social interaction that sustained flexible coordination and cooperation. The more skilled, the more talented, and the more intelligent individuals must have held positio ...
... demise of many leaderless hominid social formations, and the consolidation of new hominid social relations based on novel forms of social interaction that sustained flexible coordination and cooperation. The more skilled, the more talented, and the more intelligent individuals must have held positio ...
Darwin and Galton - The University of Texas at Dallas
... Excerpt from Darwin’s journal "The most curious fact is the perfect gradation in the size of the beaks in the different species of Geospiza, from one as large as that of a hawfinch to that of a chaffinch, and ... even to that of a warbler... Seeing this gradation and diversity of structure in one sm ...
... Excerpt from Darwin’s journal "The most curious fact is the perfect gradation in the size of the beaks in the different species of Geospiza, from one as large as that of a hawfinch to that of a chaffinch, and ... even to that of a warbler... Seeing this gradation and diversity of structure in one sm ...
Chapter 1 The Framework of Biology
... Darwin studied Charles Lyell's Principles of Geology which proposed evidence that the earth was older than previously thought and environments changed over time. Five postulates summarize Darwin's ideas. The five postulates are: life evolves, gradualism, multiplication of species, common descent wit ...
... Darwin studied Charles Lyell's Principles of Geology which proposed evidence that the earth was older than previously thought and environments changed over time. Five postulates summarize Darwin's ideas. The five postulates are: life evolves, gradualism, multiplication of species, common descent wit ...
Evolution Study Guide
... 4. Sexual Selection Certain traits increase the likelihood of finding a mate and therefore passing on genes (fitter) Ex: Why the pale peacock is so colorful. ...
... 4. Sexual Selection Certain traits increase the likelihood of finding a mate and therefore passing on genes (fitter) Ex: Why the pale peacock is so colorful. ...
Evolution Class Notes
... • If they do not have the traits (genes) that enable them to survive…they die, and DO NOT reproduce. • If they do have the traits, then they survive…and reproduce. – SO… the next generation has more of the “fit” traits for THAT environment. ...
... • If they do not have the traits (genes) that enable them to survive…they die, and DO NOT reproduce. • If they do have the traits, then they survive…and reproduce. – SO… the next generation has more of the “fit” traits for THAT environment. ...
Natural Selection
... Describe what is happening in the picture above. How is the population of mice different in figure 3 than in figure 1? ...
... Describe what is happening in the picture above. How is the population of mice different in figure 3 than in figure 1? ...
key - Sacramento State
... nature and the degree to which competition for limited resources acted to limit individual survival and reproduction. The logical consequence Darwin put forth based on these observations was that the most competitive individuals would persist and reproduce, whereas those that are not would die. ...
... nature and the degree to which competition for limited resources acted to limit individual survival and reproduction. The logical consequence Darwin put forth based on these observations was that the most competitive individuals would persist and reproduce, whereas those that are not would die. ...
NATURAL SELECTION AT WORK
... come in two varieties, one darker than the other. • Before the industrial revolution, the dark moth was rare; however, during the industrial revolution the light moth seldom appeared. ...
... come in two varieties, one darker than the other. • Before the industrial revolution, the dark moth was rare; however, during the industrial revolution the light moth seldom appeared. ...
Ch. 4 Evolution - gettingbuggywithit
... Sources of Variation • Mutation create the variation necessary for Natural Selection – Mutations are random changes in the DNA sequence in a chromosome – Caused by environmental factors (chemical, radiation or viruses) or in errors when the cell makes copies of the DNA – Only the mutation to the ch ...
... Sources of Variation • Mutation create the variation necessary for Natural Selection – Mutations are random changes in the DNA sequence in a chromosome – Caused by environmental factors (chemical, radiation or viruses) or in errors when the cell makes copies of the DNA – Only the mutation to the ch ...
How Populations Evolve
... the branching sequence of an evolutionary tree Some homologous characters, such as the genetic code, are shared by all species because they date to the deep ancestral past In contrast, traits that evolved more recently are shared by smaller groups of organisms ...
... the branching sequence of an evolutionary tree Some homologous characters, such as the genetic code, are shared by all species because they date to the deep ancestral past In contrast, traits that evolved more recently are shared by smaller groups of organisms ...
Natural Selection & Evolution
... resembled a mainland finch, but there were more types Bill shapes are adaptations to different means of gathering food. ...
... resembled a mainland finch, but there were more types Bill shapes are adaptations to different means of gathering food. ...
Chapter 15 and 16 Quiz
... d. Charles Lyell. 5. Darwin realized that the economist Malthus’s theory of population control a. applied only to humans. b. could be generalized to any population of organisms. c. could be generalized only when populations lived in crowded conditions. d. explained why the number of deaths exceeded ...
... d. Charles Lyell. 5. Darwin realized that the economist Malthus’s theory of population control a. applied only to humans. b. could be generalized to any population of organisms. c. could be generalized only when populations lived in crowded conditions. d. explained why the number of deaths exceeded ...
History of Life and Evolution Notes – part I History of Life Biogenesis
... Natural Selection accounts for Descent with Modification as species become better adapted to different environments. ...
... Natural Selection accounts for Descent with Modification as species become better adapted to different environments. ...
Problems in sexual selection theory and neo
... biologists.18 He also claimed that in no case has it been demonstrated scientifically that sexual selection in wild populations has significantly changed an animal’s physical traits. This conclusion is not unexpected, because it would be necessary to show not only that the females selected males wi ...
... biologists.18 He also claimed that in no case has it been demonstrated scientifically that sexual selection in wild populations has significantly changed an animal’s physical traits. This conclusion is not unexpected, because it would be necessary to show not only that the females selected males wi ...
Document
... Their offspring will have larger than average tails and their female offspring will fancy long tails. The sons can have more than average offspring; and the daughters will have sons similarly blessed. Positive feedback leading to runaway growth in tail length. WHY should females prefer any particu ...
... Their offspring will have larger than average tails and their female offspring will fancy long tails. The sons can have more than average offspring; and the daughters will have sons similarly blessed. Positive feedback leading to runaway growth in tail length. WHY should females prefer any particu ...
Evolution by Natural Selection
... • There is variation within any species. • Species tend to produce far more offspring than are necessary for survival of that species. • There is a limited amount of resources ...
... • There is variation within any species. • Species tend to produce far more offspring than are necessary for survival of that species. • There is a limited amount of resources ...
Evolution Study Guide Answers
... 18. When a species produces more offspring than it has resources, this is known as Overproduction 19. If there are more organisms than resources, Competition will occur between members of the same species. This does not mean animals of the same species will fight one another but simply that some wi ...
... 18. When a species produces more offspring than it has resources, this is known as Overproduction 19. If there are more organisms than resources, Competition will occur between members of the same species. This does not mean animals of the same species will fight one another but simply that some wi ...
Sexual Dimensions February 2013
... human condition and the relationship between sensation, perception, emotion, thought, and action. Sigmund Freud and Otto Rank, Freud’s protégé for a portion of their careers, disputed the role of sex vs. death in society and the motivation for Art2. States of Consciousness and Energy Systems In the ...
... human condition and the relationship between sensation, perception, emotion, thought, and action. Sigmund Freud and Otto Rank, Freud’s protégé for a portion of their careers, disputed the role of sex vs. death in society and the motivation for Art2. States of Consciousness and Energy Systems In the ...
Wilmot Evolution Review
... Over generations, the members of isolated populations may become more and more different. Isolated populations may become genetically different, as those that are better adapted to the new environment survive and reproduce. Random processes such as mutation and genetic drift can also effect evolutio ...
... Over generations, the members of isolated populations may become more and more different. Isolated populations may become genetically different, as those that are better adapted to the new environment survive and reproduce. Random processes such as mutation and genetic drift can also effect evolutio ...
Common Disciplinary Problems
... Sexual Harassment • Submission to or rejection of such conduct either is: • made a term or condition of a person’s job, pay, or career, or • is used as a basis for career decisions OR• Such conduct unreasonably interferes with performance or creates an intimidating, hostile, or offensive work envir ...
... Sexual Harassment • Submission to or rejection of such conduct either is: • made a term or condition of a person’s job, pay, or career, or • is used as a basis for career decisions OR• Such conduct unreasonably interferes with performance or creates an intimidating, hostile, or offensive work envir ...
Sexual selection
Sexual selection is a mode of natural selection where typically members of one gender choose mates of the other gender to mate with, called intersexual selection, and where females normally do the choosing, and competition between members of the same gender to sexually reproduce with members of the opposite sex, called intrasexual selection. These two forms of selection mean that some individuals have better reproductive success than others within a population either from being sexier or preferring sexier partners to produce offspring. For instance in the breeding season sexual selection in frogs occurs with the males first gathering at the water's edge and croaking. The females then arrive and choose the males with the deepest croaks and best territories. Generalizing, males benefit from frequent mating and monopolizing access to a group of fertile females. Females have a limited number of offspring they can have and they maximize the return on the energy they invest in reproduction.First articulated by Charles Darwin who described it as driving speciation and that many organisms had evolved features whose function was deleterious to their individual survival, and then developed by Ronald Fisher in the early 20th century. Sexual selection can lead typically males to extreme efforts to demonstrate their fitness to be chosen by females, producing secondary sexual characteristics, such as ornate bird tails like the peacock plumage, or the antlers of deer, or the manes of lions, caused by a positive feedback mechanism known as a Fisherian runaway, where the passing on of the desire for a trait in one sex is as important as having the trait in the other sex in producing the runaway effect. Although the sexy son hypothesis indicates that females would prefer male sons, Fisher's principle explains why the sex ratio is 1:1 almost without exception. Sexual selection is also found in plants and fungi.The maintenance of sexual reproduction in a highly competitive world has long been one of the major mysteries of biology given that asexual reproduction can reproduce much more quickly as 50% of offspring are not males, unable to produce offspring themselves. However, research published in 2015 indicates that sexual selection can explain the persistence of sexual reproduction.