It looks like you're using Internet Explorer 11 or older. This website works best with modern browsers such as the latest versions of Chrome, Firefox, Safari, and Edge. If you continue with this browser, you may see unexpected results.
Encyclopedias are a very good place to start your research. They can help you narrow your topic, define terminology that you may not understand, and lead you to references of primary articles that you can use for your research.
The Encyclopedia of Biodiversity is a scholarly resource containing over 300 articles by leading international authors. It is a comprehensive survey of biodiversity, across taxonomic groups and ecological regions. Topics covered include agriculture, conservation and restoration, economics, environmental conditions and effects, evolution, extinctions, genetics, geographic and global issues, habitats and ecosystems, human effects and interventions, and population issues.