Island adopted by strangely intense scientist (8)
I believe the answer is:
einstein
'scientist' is the definition.
(Einstein is an example)
'island adopted by strangely intense' is the wordplay.
'island' becomes 'i'.
'adopted by' means one lot of letters goes inside another (I've seen this in other clues).
'strangely' is an anagram indicator.
'intense' anagrammed gives 'einsten'.
'i' inserted inside 'einsten' is 'EINSTEIN'.
(Other definitions for einstein that I've seen before include "Famous scientist of the nineties" , "'German physicist, in the nineties (8)'" , "German expert on relativity" , "Physicist who formulated theories of relativity" , "Iconic theoretical physicist, d. 1955" .)