FIRST: Read the background information on the Living fossils tab to understand the concept of living fossils.
THEN: Go to the tabs in this box and select one of the “living fossils” provided there. Alternatively, you can do you own research on this idea and select something that is not listed. If you have any questions about your selection, please reach out to your instructor.
NEXT: See assignment details in the course for what to include in your post. Use OneSearch if you need to find additional sources.
Species of animals and plants that have changed little over long periods of evolutionary history to the present. Examples are the lungfishes, alligators, snapping turtles and the aardvark. They are thought by some to present a thorny problem for traditional gradualistic evolution: if Natural selection is continuously reshaping species, why have some species apparently escaped? Darwin seems to have originated the term ‘living fossil’ (first edition of On the Origin of Species by Means of Natural Selection, p. 107) suggesting that they were preserved because they have inhabited confined areas and thus avoided Competition. However, many species of living fossil have broad distributions. Some believe they have persisted because of narrow specialized adaptations; others because they have unusually broad unspecialized adaptations. Possibly no one answer applies. Equally, to suggest that they have remained unchanged because some aspect of their ecology has enabled them to avoid selection pressures is, in itself, somewhat vacuous if not circular. See also punctuated equilibrium. [P.C.]
Living fossils. (1998). In P. Calow (Ed.), The encyclopedia of ecology and environmental management, Blackwell science. Blackwell Publishers.
In this assignment you will need to locate at least 4 resources that you can use in your paper/project. These should be focused on your species that you selected in module 1, its evolution, and the fossil record that examines this species. You should also look for sources that discuss the way this species evolved. See full assignment details in your course.
Below are tip sheets, tutorials and search tips to help you find sources and complete your annotated bibliography.
In the Search Tools box (below), click on the Advanced Search link under the OneSearch box. You will then see 3 search boxes that you can use to divide your topic into its main ideas.
In the top box, type the species you are researching. If it's a two-part name, like "African Elephant," put the name in quotation marks. The quotation marks mean that you are searching those words as a phrase, not as individual keywords. Changing the drop-down list next to the box from Select a field (optional) to SU Subject terms will limit your search to only articles that include the animal as a subject term. Try it both ways!
In the second box, type the concept you are searching. Suggested terms include evolution, "fossil record," "genetic drift," or selection. Again, use quotation marks if you are searching for a specific phrase of more than one word.
Here's an example search:
You can limit your results with the Refine Results column on the left side of the page. Try limiting by date or resource type.
As you review your results, take note of the subject headings and keywords you are reading. They can help you create new searches to find more information.
As always, if you need assistance, contact your librarians. We are happy to help!
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