Provide information about Darwin's Finches.

(N/A) During his voyage,$Charles \ Darwin$ visited the $Galapagos$ Islands.
He observed an amazing diversity of creatures there.
He was particularly amazed by small black birds,which were later called $Darwin's \ Finches$.
He observed many varieties of finches on the same island.
He conjectured that all the varieties had evolved on the island itself from an original seed-eating ancestor,a process known as $Adaptive \ Radiation$.