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8th Grade Science EVOLUTION
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Fold your paper in half hot dog style, label one side before and one side after as organized below
What is evolution? I think evolution is… What is a Mutation? I think mutations are… What is a ‘common ancestor’? I think common ancestor means… What is evolution? The change of a species over time What are mutations? Mutations occur when there is a modification to an organism’s DNA which cause some kind of change in an organism. What is a common ancestor? A common ancestor is an organism from long ago that all living things came from via evolution. What is evolution?
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Biological EVOLUTION Geological Technological
Draw this diagram on the back of your before/after notes Biological The change of living organisms over time Evolution does not only refer to the change of a species over time, we can use it to describe any change over time EVOLUTION A change over time Geological Technological The change of the earth over time Ex: continental drift, mountains forming, erosion, etc. The change of technology over time Ex. Phones, cell phones, computers, agricultural, biotechnology
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VI. Three Way Tie – In the graphic organizer below, write the definition for the terms in the boxes provided. On the lines connecting the terms, describe how the terms are related. Evolution: A change in the inherited traits of a species from one generation to the next Evolution is a process that describes how a species changes over time Extinction is what happens when an organism does not evolve Species: A group of organisms that are able to produce offspring that are healthy and capable of reproducing Extinction is when a species completely disappears Extinction: When all of the organisms within a species die (over a relatively short period of time)
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Whale Evolution
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Evolution and Adaptation Notes
8th Grade Science Spring 2014
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Examples of different species:
Species – A group of organisms that are able to produce offspring that are healthy and capable of reproducing together. Examples of different species: Humans, blue whales, dogs, dogwood trees, grey squirrels, white tailed deer, etc. Biological classification: a system which is used to precisely describe, organize and classify all the life on Earth. Creating a classification system allows scientists to examine the relationships between various organisms and construct evolutionary trees Also referred to as taxonomy.
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II. Biological Evolution – a change in the inherited traits of a species from one generation to the next. Because every organism has unique DNA, some organisms within a species are better suited for certain environmental changes than others (genetic variation). Adaptation: inherited characteristic that increases an organism's chance of survival Biologic changes: the change in an organism's genetic makeup, DNA, that occurs through natural selection of advantageous traits for survival over an extended period of time
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b. Organisms within a species that are not well suited for a certain environment will not survive.
Natural Selection: process by which individuals that are better suited to their environment survive and reproduce most successfully; also called survival of the fittest Watch this BrainPop video on Natural Selection & answer the questions on your note sheet What did Darwin notice about the beaks of the finches on each island? What is the survival of the fittest? c. The result is that the characteristics of a species will change when the environment changes. d. Within a species, the greater the diversity in phenotypic traits (such as body structures and characteristics), the greater the chances are for that species to survive during environmental change.
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e. Geographic Changes: the change in a geographic area caused by earthquakes, volcanoes, mountains forming, and other natural phenomena i. Plate Techtonics Theory: the movement of Earth’s continental and oceanic plates have caused changes in climate, mountains and deep ocean trenches to form and continually change the shape of Earth’s crust throughout time ii. Natural processes and human activities result in environmental changes f. If all of the organisms within a species are unable to adapt to an environmental change, the species will become extinct. Extinction – when all of the organisms within a species die in a relatively short period of time. Most species that have lived on the Earth are now extinct Some organisms that lived long ago are similar to currently existing organisms, but some are quite different Extinction of organisms is apparent in the fossil record
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III. Scientists who studied evolution
g. Theory of Evolution: the theory that organisms/species change over time, caused by the natural selection of advantageous traits for survival in a particular environment; this theory also proposes that all organisms evolved from a common ancestor(s) i. As random genetic mutations occur within an organism’s genetic code, beneficial mutations are passed on to the next generation III. Scientists who studied evolution Gregor Mendel “Father of Genetics” Studied how traits were passed from one generation to the next in pea plants. Charles Darwin “Father of Evolution” Studied how organisms within a species change when they move to new environments. Traveled to the Galapagos Islands and observed natural selection at work when he studied the iguanas, finches, and tortoises.
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IV. Proof that organisms change over time
Fossils – prove that the types of organisms on Earth have changed throughout history (example – dinosaurs). Rocks – prove that the Earth’s plates have moved over time, which impacts the environments in which organisms live (example – there are sea shell fossils in the rocks on Mt. Everest). Ice cores – when scientists drill into polar ice caps, there is evidence that the climate has changed throughout Earth’s history. Climate change impacts the environment in which organisms live (example – ocean temperature being raised as a result of global warming impacts the organisms living in the ocean).
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V. Evidence of Evolutionary Descent
a. The fossil record enables the reconstruction of evolutionary history, scientists study: Comparative anatomy: the study of anatomical (physical) features of animals of different species Homologous body structures: similar body structures and systems between different species Embryological similarities: similarities in the embryonic stage of development between different species
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