Thank you for your question about English phrases on Ask A Question e-reference service. AAQ is a service for Albertans, or for those with questions about Alberta. It time permits, we do assist with other quesstions.

According to the Random House Dictionary of Popular Proverbs and Sayings, 'necessity is the mother of invention' means that "dire situations inspire ingenious solutions. If worst comes to worst, people will apply all their imagination and skill to deal with the problem." In Latin, the phrase is 'Mater artium necessitas'; it appears in several other languages as well. The phrase has been traced back to 'Vulgaria' (1519).

http://www.phrases.org.uk/bulletin_board/17/messages/524.html

I hope this information helps.