They could be slow but wise in development (4)
I believe the answer is:
owls
'they' is the definition.
Both the definition and answer are plural nouns.
Perhaps you can see a link between them that I don't see?
'be slow but wise in development' is the wordplay.
'slow' anagrams to 'OWLS'.
But, I am unsure how this is indicated.
'could' is the link.
Can you help me to learn more?
(Other definitions for owls that I've seen before include "Nocturnal bird" , "Night birds" , "Strigiform creatures" , "Slow sort of birds" , "Slow kind of birds" .)