Distant relatives extremely anxious about exercise
I believe the answer is:
apes
'distant relatives' is the definition.
The definition and answer can be both animals as well as being plural nouns.
Perhaps there's a link between them I don't understand?
'extremely anxious about exercise' is the wordplay.
'extremely' suggests removing the centre (only the extremes of the word are used).
'about' indicates putting letters inside.
'exercise' becomes 'pe' (Physical Education).
'anxious' with its centre removed is 'as'.
'as' enclosing 'pe' is 'APES'.
Can you help me to learn more?
(Other definitions for apes that I've seen before include "Imitates in every aspect" , "Copies the primates?" , "Zoo animals" , "Species of primate" , "Peas (anag)" .)