The first step in choosing keywords is to think about what information you need to search for. This seems obvious, and to a certain extent you are probably already doing it. But a more systematic approach will reward you.

1. Break the search down into the key concepts:

   • hawk moth and tongue
2. Brainstorm (or look for in your background reading) synonyms. Tip: You will get more results if you use the common and scientific names for organisms.
   • hawk moth OR sphingidae
   • tongue OR proboscis
3. Combine these terms in a logical way:
   • OR: combines synonyms -  hawk moth OR sphingidae (either of these concepts should be present in results - not ALL terms need to be present)
   • 
   • AND: use when combining different concepts since both these concepts need to be present in results
   • (hawk moth OR sphingidae) AND (tongue OR proboscis)
4. Things to consider when considering words/terms to include in your search:
   • think of synonyms
   • think of plural and singular variations of words (e.g. moth or moths)
   • use truncation to search for singular and plural versions of words: (e.g. moth*)
   • think of spelling variations: (e.g. behaviour OR behavior)

Below are some helpful textbooks and readings for additional background in geomorphology: