4.5 billion years ago \uf0e0 earth. First signs of animal life was a billion years after that.<\/p>\n
Amino Acids: proteins in cells (found in lightning).<\/p>\n
Darwin: interest in natural history, collected minerals, bird\u2019s eggs, insects etc. Did not do well in school, went to medical school, graduated at 22.<\/p>\n
No theory about evolution. Did species evolve from other species, or did they come in a different time in creation? Either God created animals to change their form, or that God created life.<\/p>\n
Darwin saw a variety of animal types he had never seen before. Lived in separate, distinct groups.<\/p>\n
Read an essay by Malthus \uf0e0 concluded that human pop\u2019n would double if they were not kept in check by food supply and economics.<\/p>\n
Theory of Natural Selection<\/p>\n
1)\u00a0\u00a0\u00a0 Organisms are different in some way form each other, and some of these differences are based on heredity.<\/p>\n
–\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Criticized for being biologically deterministic.<\/p>\n
2)\u00a0\u00a0\u00a0\u00a0 Organisms over produce.<\/p>\n
Darwin reasoned that individuals who have inherit differences that are more adaptive (better enabled to cope with environmental factors to survive and reproduce) will tend to live longer, reproduce, pass these traits on to future offspring.<\/p>\n
Saw lots of birds on the island, mainly finches, and lived in groups. They separated from each other, and were different in beak structure.<\/p>\n
This is what is meant by \u201cSurvival of the Fittest\u201d. Fitness, in a Darwinian context referred to traits that were best suited to the animals in the environment.<\/p>\n
Evolution is not always physical, in humans we use the opposable thumb as our example of evolution. BUT it is also behavior:<\/p>\n
Socio Political Aspects on Darwin\u2019s Theory<\/p>\n
\u201cSurvival of the fittest\u201d \uf0e0 Phrase by Spencer. Believer in Laisse faire philosophy (right wing extremist) –\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Evoked Darwinian theory to say that competition is the natural order of things. –\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Government should not interfere with this natural order.<\/p>\n
BUT this is flawed<\/p>\n
1)\u00a0\u00a0\u00a0 Naturalistic fallacy: mistaken belief that what is natural is also what is good or right. Confusion between what is and what ought to be.<\/p>\n
Ex. Death, disease, pain, loneliness.<\/p>\n
Science deals with what IS, but not necessarily is ought to be. Not a rationale for the order of things.<\/p>\n
Applying the theory to society<\/p>\n
2)\u00a0\u00a0\u00a0\u00a0\u00a0 What is natural is immutable \uf0e0 unchangeable.<\/p>\n
This isn\u2019t necessarily a rule, you can change some things. This is NOT\u00a0 valid statement.<\/p>\n
E.g. Marx \u2013 fan of Darwin\u2019s theory, and wrote that Darwin\u2019s theory is the basis of natural history and socialism.<\/p>\n
Marx assumed that you can change this behaviour to have the correct socio-economic system.<\/p>\n
Why does evolution need Darwin?<\/p>\n
Most people like sweet things \uf0e0 why? They activate certain end organs of your tongue (Ultimate) or they taste good (proximate).<\/p>\n
Psychology focuses on Ontogenetic causes: pertains to development within a single individual, within their lifespan. From embryo to death.<\/p>\n
\uf0b7\u00a0\u00a0\u00a0\u00a0\u00a0 Psychology tends to ignore this.<\/p>\n
Ex. They spend time on human family dynamic. No where do they question the ultimate question like why do people live in families in the first place?<\/p>\n
Some species live in families, and some do not.<\/p>\n
Psycho-linguistics<\/p>\n
Being a proximate or ultimate is not necessary, they all have their special aspects. There is a dichotomy between the 2.<\/p>\n
Why did sex evolve? In comparison to the less sexual ways (like splitting cells). You lose half your genetic data.<\/p>\n
Sex drive decreases after the first year, or after a child. WHY? Better chance of survival if you have offspring, and it allows the pair to focus time\/energy\/attention on the offspring. Males drop in T after the child is born so they are focused on a child.<\/p>\n
Many say that culture is a big determinant of our behaviour, not just our evolutionary past. But they say that we do these things, and that\u2019s why we have a big brain. We developed opposable thumbs because they enabled us to be better tool makers.<\/p>\n
Saying that something is based on culture is NOT SCIENTIFIC. Theory of Culture has no explanatory values for behavior, unless you are looking at cultural traits.<\/p>\n
Psychology will never function at the level of biology, because it does not serve to the ultimate question, but only the proximate.<\/p>\n
Opposing to Darwin\u2019s theory. (Or more feasible)<\/p>\n
Blending theory: there was a blending of the protoplasm and that\u2019s how a child acquired their parent\u2019s attributes.<\/p>\n
Took till the 1930s until someone used natural selection in terms of genes and traits.<\/p>\n
\uf0e0 \u201cThe synthetic theory of evolution\u201d It syntehesized Darwin and Mendel\u2019s theory of evolution.<\/p>\n
Genes are no longer limited to the individual, it is also the parenting behaviour. There are genes for good parenting, and these genes will emerge to offspring later on.<\/p>\n
\uf0e0 Explains why parents give so much time to their children. It is related to their own survival.<\/p>\n
Natural selection needs variation, and genetically based differences between individuals.<\/p>\n
What are the sources of variation? \uf0e0 nature and cause of variability<\/p>\n
\uf0b7\u00a0\u00a0\u00a0\u00a0\u00a0 MUTATION<\/p>\n
\uf0b7\u00a0\u00a0\u00a0\u00a0\u00a0 The process of sexual reproduction<\/p>\n
\uf0e0 It contributes to variation, and variation is the basis of natural selection. It does still seem limited in the basis of variation.<\/p>\n
A discovery in the 1930s has an answer to this dilemma \uf0e0 sexual reproduction shows more variation than you would expect. \u2013 RECOMBINATION<\/p>\n
\uf0b7\u00a0\u00a0\u00a0\u00a0\u00a0 Gene shuffling, recombination, cross-over phenomenon. Happens in miosis. Pairs of chromosomes and germal cells split to form a GAMETE (sex cells)<\/p>\n
Crossover has replaced mutation as the source of variation.<\/p>\n
There are 3 major kinds of natural selection<\/p>\n
Why do we have so many extinct species with so much change? Why not just a world full of beetles? \u201cRed Queen Theory\u201d: \u2018keep running to stay in the same place\u2019.<\/p>\n
Ex. Lions and antelopes. Lions are predators. As the lions hunt antelopes, the slowest ones are eaten, the less cunning are eaten. The fastest will survive. The lions ALSO have to become faster to survive. Both need to be constantly adapting to survive.<\/p>\n
Humans have the most amount of change \u2013 we do have predators. Viruses. They can contribute to evolutionary change within the human species.<\/p>\n
Competition is in our genes.<\/p>\n
Punctuated equilibria: put forth by Eldridge and Gould \uf0e0 the most significant evolutionary changes, including the development of a species is episodic. They are in hundreds of thousands of years. Like the Camridian explosion. Period of 10,000 years.<\/p>\n
Permian Extinction: 50% of marine creatures became extinct because of the fusion of the land masses, which created shallow waters. Animals who fed on fish in the shallow waters had less food.<\/p>\n
Ice Age: cretian extinction \u2013 75 mill. Years ago.\u00a0 A quarter of species were eliminated, the end of the dinosaurs, which opened a way of the rise of the mammals.<\/p>\n
Assumes these and many other are the basis of the intense variation we see, and the basis for natural selection.<\/p>\n
Autralopithicaus Africanus is the first known relative to the human species. No fossil records for the differences in these fossils. But theory is that speciation occurs too quickly to be seen in fossils.<\/p>\n
Murdock (1945): made a list of traits known to exist in every culture in history<\/p>\n
Monday, September 30, 2013<\/p>\n
Social definition:<\/p>\n
Biological definition: any behaviour which enhances the fitness of others at the expense of the helper. –\u00a0\u00a0\u00a0\u00a0\u00a0 No motivation, or intention.<\/p>\n
An individual that produces few offspring is altruistic \uf0e0 every kid you don\u2019t have will leave more resources for others.<\/p>\n
Wyn-Edwards: relationship between the amount of food a population consumes, to the degree that the food is replenished\/maintained.<\/p>\n
Hunting: weed out the weaker animals, and the stronger ones reproduce. Pass the critical maximum, you wipe out the strong and the weak until the species are destroyed.<\/p>\n
This works through opimization: [LAK] how females control reproduction \uf0e0 how often she lays eggs, how many eggs per season etc. She adjusts her reproduction potential with the size of the flock. If the pop\u2019n is overcrowded, the reproductive system will shut down.<\/p>\n
The epiditec display: observe the flock flying at dusk, and the females bird take a consensus about the number of birds in the flock and how to reproduce accordingly.<\/p>\n
One study about this in birds: attempt to control the rook size in Scotland. They shot the rooks, and got paid. But this did not work, the females just doubled up on their eggs when they saw there were less birds.<\/p>\n
Overcrowding in rats: [Lachoots?] he overcrowded the rats. The females became infertile, ate their young, males became homosexual, and by doing this they optimized.<\/p>\n
\uf0b7\u00a0\u00a0\u00a0\u00a0\u00a0 Can get optimization in something like a virus: lyxoma virus. Brought into Scotland to control the rabbit pop\u2019n.<\/p>\n
Dawkin\u2019s: sneezing is a way of pop\u2019n control. It gets the virus into a new host. What is the physiological response to humans?<\/p>\n
Another mechanism for pop\u2019n control is<\/p>\n
Helpers at the nest: birds will go to other nests and help the babies in that nest.<\/p>\n
Thompson Gazelle: if there is a danger, the first gazelle that sees the danger begins to alert the whole troop and they would flee. You make yourself more vulnerable.<\/p>\n
Bees have kamakazee bees that sniff out ones that don\u2019t belong. They kill them but die in the process.<\/p>\n
Baboons: will distract the enemy from the rest.<\/p>\n
Young men\/women in the prime of reproductive life: going to fight a war.<\/p>\n
\uf0b7\u00a0\u00a0\u00a0\u00a0\u00a0 Nothing in natural selection accounts for this, or making self sacrifices for others.<\/p>\n
Individual selection: competition between individuals.<\/p>\n
Group selection: competition between groups \uf0e0 a group has an advantage of reproducing compared to another. The individual may be disadvantaged but the group has benefits. \uf0b7\u00a0 Ex. 5 by 5 basketball (group) vs. one on one (individual)<\/p>\n
Misconceptions<\/p>\n
Group selection means survival of species: too wide a scope. They do not die for their species. It refers to herds of gazelles, group of monkeys etc.<\/p>\n
Huxley: advocate of group selection to justify strong government control. Work for the group, work for the state.<\/p>\n
\uf0b7\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 May have had group selection because you could not stand the selfishness of individual selection.<\/p>\n
Third level of selection:<\/p>\n
Kin selection (inclusive fitness): 1960s by Smith.<\/p>\n
Twice as nice to siblings as you would be to nieces and nephews, cousins etc.<\/p>\n
Hamiliton\u2019s theory: non-reproductive castes of insects<\/p>\n
Hymenoptera: ants, bees, etc. Are said to be eusocial: he highest order of social order.<\/p>\n
Heploid\/Diploid: males come from non-fertilized eggs. They were strongly related to each other than to their own offspring if they had any.<\/p>\n
100% of their genes they share with their father are alike. 50% of their genes with their mother, and share 75% of their genes with their sisters. More related to their sisters than their mothers.<\/p>\n
\uf0b7 With inclusive fitness, they became sterile so the queen could generate more. \uf0b7\u00a0\u00a0\u00a0\u00a0\u00a0 Fitness is increased by investing in your sisters than your own.<\/p>\n
Diploid\/diploid: only one set of chromosomes for males.<\/p>\n
Multi level selection: all 3 levels can be operated in the individual at different circumstances. Can sacrifice different levels for the group, including your life.<\/p>\n
How far does kin selection extend: no farther that second cousins. Others say much farther, and it can account for ethnocentricism.<\/p>\n
E.O Wilson: as wars increased and economic downfalls emerged, then ethnocentricism increased.<\/p>\n
Fourth level of selection<\/p>\n
Gene selection: (Dawkins) \u2013 all natural selection operates at the level of the gene. Construct individuals to be designed for their own survival and replication.<\/p>\n
Morning sickness: adaptive function. Infant pushing the mother into the fact that she was feeding him potentially toxic food.<\/p>\n","protected":false},"excerpt":{"rendered":"
4.5 billion years ago \uf0e0 earth. First signs of animal life was a billion years after that. First forms were simple, and bacterial. First 3 billion years, nothing more… Continue Reading Darwin\u2019s Theory of Evolution\/Natural Selection<\/span><\/a><\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[109],"tags":[],"_links":{"self":[{"href":"https:\/\/www.amyork.ca\/academic\/zz\/wp-json\/wp\/v2\/posts\/4322"}],"collection":[{"href":"https:\/\/www.amyork.ca\/academic\/zz\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.amyork.ca\/academic\/zz\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.amyork.ca\/academic\/zz\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/www.amyork.ca\/academic\/zz\/wp-json\/wp\/v2\/comments?post=4322"}],"version-history":[{"count":0,"href":"https:\/\/www.amyork.ca\/academic\/zz\/wp-json\/wp\/v2\/posts\/4322\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.amyork.ca\/academic\/zz\/wp-json\/wp\/v2\/media?parent=4322"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.amyork.ca\/academic\/zz\/wp-json\/wp\/v2\/categories?post=4322"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.amyork.ca\/academic\/zz\/wp-json\/wp\/v2\/tags?post=4322"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}