..If you plan to use open/free resources found on the internet for an academic task, question the source and verify the data/information.
..A few tips:
..Authority & reliability: remember to check the "About us" file or "Mission" statement to find out who's running the show and verify that the editor/author/organization has some expertise in the subject being presented.
..Credibility: facts presented that cannot be corroborated in other sources should be treated as suspect.
..Bias: not always obvious. Everyone knows that a 'dot com' is a commercial site that is probably trying to sell you something. But people, organizations, governments, and other entities also "sell" ideas: believe our story; see it OUR way; these are The Facts (or at least the ones WE like and we'll just ignore the others). Be aware that persuasion and advocacy are forms of bias: even worthy organizations like the American Cancer Society are trying to persuade you to their way of thinking.
When searching in Google, consider adding "site:edu" or "site:gov" or "site:org" to restrict your results to colleges & universities, or the US government, or non-commercial organizations.
The EOL is a partnership of institutions - including the Smithsonian Institution, the Marine Biological Laboratory, and Harvard University - to co-locate verified scientific information about every life-form on Earth. This link goes directly to the section on Elasmobranchii, but other searches can be performed. The section has many subsection, so be sure to open the tabs BEYOND the Overview subsection!
Sponsored by sch scientific partners as the European Network for Biodiversity Information, the California Academy of Sciences, and the Food and Agriculture Organization of the United Nations, FishBase brings together descriptive information on over 33,000 species of fish, accompanied by references to the research literature. Both common and scientific names may be used for searching.
Science.gov is a gateway to US government science information and research results. Currently in its fifth generation, Science.gov provides a search of over 55 scientific databases and 200 million pages of science information with just one query, and is a gateway to over 2100 scientific Websites