Presentation on theme: "Thought Question What evidence did the scientist in Great Transformations find that indicated whales evolved from land animals?"— Presentation transcript:
1Thought QuestionWhat evidence did the scientist in Great Transformations find that indicated whales evolved from land animals?
2Theory vs. Law Law = statement about a repeatable event Theory = explanation of a natural phenomena based on extensive evidenceBoth are considered factual understandings of the natural world.One cannot become the other, they exist independently of each other and serve different purposes.
3The Three Foundational Theories of Biology Cell TheoryGerm TheoryTheory of Evolution
4Cell Theory All living things are composed of cells Cells are the basic units of structure and function in living thingsNew cells are produced from existing cellsAreas of science that have contributed:Cell biologyMicrobiologyMicroscopy
5Germ theoryInfectious diseases are caused by microorganisms of different types, commonly called germsAreas of science that have contributed:Cell biologyMicrobiologyEpidemiologyBacteriologyVirologyPathologyParasitology
6Theory of EvolutionEvolution: changes in gene frequencies in a population over time or “descent with modification”Explanation for diversity of life on EarthSpecies alive today are descended with modification from ancestral species. This process of changes from common ancestors unites all organisms on Earth.
7History of Evolutionary Theories 1800s Europe:Dominant belief was that Earth and all its forms of life had been created a few thousand years ago and since then neither the planet nor its living species had changed
8History of Evolutionary Theories James Hutton, 1795GeologistWHAT: Published hypothesis about the layers of rock, formation of mountains, erosion, etc that occurs over millions of yearsWHY: Could no longer measure the history of the planet in terms of human lifetimes
9History of Evolutionary Theories Jean-Baptiste Lamarck, 1809French naturalistWHAT: Species changed through acquired characteristicsExample: if you lift weights, your children will have big musclesIncorrect, but did begin to explain adaptationWHY: Idea that species change
10History of Evolutionary Theories Charles Lyell, 1833GeologistWHAT: Argued that the formation of Earth took place through small changes over a long period of time (old Earth)WHY: Darwin expanded this to species changing over time
11History of Evolutionary Theories Darwin, set sail on Beagle 1831WHAT: Realized organisms were not fixed and unchangeable (based on fossil record and biodiversity)WHY: Provided explanation of the process of evolutionary change (theory of evolution by natural selection)
12History of Evolutionary Theories Thomas Malthus, 1798WHAT: If human population continued to grow, resources would run outWHY: Darwin applied this struggle for resources to plants and animalsan oyster produces millions of eggs in one year, a maple tree produces thousands of seeds in a single summerthey don’t all go on to live, why do some die?
13History of Evolutionary Theories Alfred Russell Wallace, 1858NaturalistWHAT: Independently thought of idea of natural selectionWHY: Ultimately lead to Darwin publishing On the Origin of Species in 1859