Evolution Notes

Marine Evolution Notes

1. Evolution

2. Evolution: Any change in the genes of a population over time

3. Origin of life: Big Bang Theory: explosion of a mass of matter to create the universe 4.6 billion years ago

4. Origin of Life Theories Abiogenic Molecular Evolution : a) Organic molecules gradually assembled from inorganic elements b) Hildane – “Hot Dilute Soup”, combination of Earth’s primitive atmosphere (H 2 0, CO 2 , Ammonia) and UV radiation created organic molecules c) Oparin – energy from the sun, lightning, and volcanic heat formed organic molecules

5. Evolutionary Theory Basics: Gradualism: slow change over time First cell was probably a “ protocell ” Membrane bound cell that reproduced Heterotrophic Prokaryotic Originated probably four billion years ago Life may have originated more than once

6. Evolution of Evolutionary Theory: Georges Cuvier: Catastrophism : Only one time of creation that populated the entire world, global catastrophe wiped out most of them. Jean Baptiste de Lamarck: Theory of Inherited Characteristics: environmental pressures and “internal desires” bring about physical changes that would be passed on to offspring

7. Evolution of Evolutionary Theory: Charles Lyell: Theory of Uniformity: The same geological processes that are occurring now, happened in the past as well *An issue for scientists as most people thought the world was only six thousand years old as noted in the Bible.

8. Charles Darwin: Naturalist aboard the H.M.S. Beagle for a five year exploration His notes became the basis of his evolutionary theories and book, The Origin of Species

9. Beginning Components of Natural Selection: Used his notes on Finches, especially in regards to their beak and diet to create his framework

10. Theory of Natural Selection: More offspring are produced than can survive All members must compete for resources All organisms show individual variations mostly due to heredity Some variations are better adapted to survive These organisms that are more likely to survive therefore reproduce, therefore increase frequency of better adaptations Change over long enough time results in new species

11. Populations: Individuals do not evolve, populations over time do A group of individuals of the same species who occupy the same area Gene Pool: all the genes present in a population, population shows variation

12. Sources of Variation: Gene mutation (produces new alleles) Crossing over at meiosis (leads to new combinations of alleles in chromosomes) Independent assortment at meiosis (Anaphase I & II, leads to mixes of maternal and fraternal chromosomes in gametes) Fertilization (puts together combinations of alleles from two parents) Changes in chromosome number or structure (lead to loss, duplication, or alteration of alleles)

13. Microevolution: Changes of gene frequencies within a population Caused by: mutation, genetic drift, gene flow, and natural selection

14. Mutation: Heritable change in DNA that can alter gene expression Can be neutral, harmful, beneficial, or lethal Original sources of alleles and thus variation

15. Genetic Drift: Random change in gene frequencies over the generations as brought about random events only

16. Gene Flow: Allele/gene frequencies change as individuals leave a population or new individuals enter a population Physical movement of genes

17. Peppered moths:

18. Development of New Species: Species: A group of organisms that breed and produce offspring that can reproduce Speciation: The development of a new species from an existing species

19. Speciation: Reproductive Isolation: groups of the same species can not contact each other and adapt to separate environments, and thus develop into different species

20. Speciation: Adaptive Radiation: One common ancestor develops into different species based on competition, location, food supply, etc. Ex: Darwins finches

21. Macroevolution: Large evolutionary changes in which new species emerge Punctuated Equilibrium: new species suddenly emerge Gradualism: Gradual, slow change over time with intermediate organisms found.

22. Evidence for Evolution: Fossil Record: Sequence of fossils Rocks formed in layers with older ones on bottom Fossils in older layers are older and simpler

23. Comparative anatomy: Comparing anatomical structures of current organisms with each other and past organisms Vestigial Organs: have no current function; appendix, wisdom teeth, penguin wings, little toe Homologous Structures: Same structure in two organisms but different functions

24. Embryonic development: Similarities in the developmental stages of embryos amongst different organisms