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Evolution and Adaptation Study focus
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Whales Whales evolved from a mammal like ancestor: Evidence: 1*fossil evidence 2*hip bone joints (where legs were, a vestigial structure) 3*Whales are mammals
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Speciation Involves : separation, adaptation, division Somehow one group gets away from the rest, maybe a canyon separates them Each group continues to adapt to it’s environment Now the groups are divided,& become new species
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Natural Selection Animals that are better adapted, survive and reproduce successfully ….this was Darwin’s Natural Selection theory….
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Evidence that Darwin never saw Genes and DNA, he never knew about that! No “CSI” back then??!!!!
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Trait A specific characteristic that can be passed from parent to offspring….. Like spots and speed on a cheetah
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Overproduction When animals produce more babies that can possibly survive, just by mere high numbers, some offspring will make it…..
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Selective Breeding is not Natural Selection, Man does this Like dogs who are bred to be good swimmers or have calmer offspring…….
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Genetics Darwin never knew about this for his theory….. He was a man before his time>
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Fossils Minerals that seep into the remains of a dead organism make fossils, ex. Animal bones..
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Division When separated groups of populations can no longer mate with each other….? Maybe water separates them They end up apart from each other, due usually to a geographic division
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Long necks Giraffes have the ability to reach high in trees for food …. This is food that most other grazers cannot get to
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Eras Scientists have divided the earth’s time into large divisions….
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Precambrian During this early time on Earth, organisms did not need oxygen
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Opposable thumbs They are helpful because they help critters grip and hold things….. Critters like us and other primates
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All Primates Have four fingers and a thumb…. A primate is: a higher level mammal, such as humans, apes, monkeys and lemurs.
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The Earliest Hominids Were found in Africa Hominids are modern human ancestors Based on the most recent fossil evidence …..
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Earths conditions slowly change.. Because of continents moving….very slow Remember plate tectonics, land masses slowly move over time …changing the map from the way we see today
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Homologous structures like hands and arms Show creatures shared a common ancestor….. The same bones are all there, just different depending on how the animal uses the limb i.e.., walk,climb,fly, swim
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Mutation Is a change in the genetic code…..
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Charles Darwin First proposed natural selection …. He sailed on the HMS Beagle (a ship) on a 5 year tour around the world. He was a “naturalist” someone who studies nature
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Theory Evolution is a theory…… We recognize that there are other ideas as well
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Adaptation A trait that helps an organism to be better suited to their environment Fish gills allow this critter to get oxygen from water Polar Bears are well suited for the cold, thick fur and fat layer
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Dark peppered moths Were harder to see during the industrial revolution in England due to the soot covered trees.. Soot comes from the burning of coal, it leaves a black dust behind Birds could not see them to eat them
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Soot is caused by coal pollution If England never stopped the pollution… And it stayed dirty, there would be more black moths, and very few if any peppered Moths are snacks for hungry birds
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Camouflage Banded snails in an environment where they are hidden will have an increase in population Banded snails hide in tall grasses on the shore line As the crawl up the blades of grass, they are well hidden from birds
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Similar body structures Scientists think that organisms with these similar structures share similar genes with a common ancestor Example: birds of today and fossil flying dinosaurs.
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Galapagos Island Finches Their beaks are adapted to eat the food available on the islands
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Survival of the Fittest Means Natural Selection This does not mean you are the biggest, just the best adapted
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A Frog with 3 front legs.. Is a mutation Scientists believe that these sad mutations are caused by chemicals in a water sheds, water pollution
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If a population is separated.. Long enough, each will become their own species
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Snowshoe rabbits Can better escape their predators as they do not get hung up in the snow. See his really big back feet. They act like snow shoes. Their survival numbers will be better than your average rabbit.
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Natural Selection Organisms best suited to their environment will pass on their traits … 1*survive 2*reproduce 3*on and on
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Radioactive dating One of the best ways to find the age of fossils…. Elements like Carbon as they decay, give off slight radiation We can measure that radiation and give a date
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Extinction The complete disappearance of a species. This is a sketch of the Dodo bird. Long extinct now due to being hunted completely out of existence.
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Embryology, the early beginnings of a creature Evidence of evolution.. Mammal embryos look similar the most….fish only in the beginning…
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Classic Example of Evolution The gradual change in the genetic make up of an entire species over a very long, long time Notice the foot had toes on it, over time, they merged into a large strong hoof that supports a bigger animal
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Good fossils ….. Birds, horses, dinosaurs, they make good fossils….. Jelly fish not so good, too soft gushy to make a fossil Most fossils needs “hard parts “
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Horses foot They have changed over time from 3 toes to one solid hoof. Great example of evolution …..
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More Vestigial Structures- anatomy that is no longer useful in a species Human tailbone:…………..> Human appendix: …………>.
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Snake Head Fish Well adapted to many areas. An invasive species.
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