No tails in the shade, perhaps (5)
I believe the answer is:
heads
'no tails' is the definition.
The answer and definition can be both animals as well as being plural nouns.
Maybe you can see a link between them that I can't see?
'shade perhaps' is the wordplay.
'perhaps' is an anagram indicator.
'shade' with letters rearranged gives 'HEADS'.
'in the' acts as a link.
Can you help me to learn more?
(Other definitions for heads that I've seen before include "a 50-50 chance" , "Goes for" , "Chiefs" , "Obverse of a coin" , "School principals" .)