The bare bones of what ancient diggers dug up of late (9)
I believe the answer is:
skeletons
'ancient diggers dug up of late' is the definition.
I can't tell whether this definition defines the answer.
'the bare bones of what' is the wordplay.
'the bare bones' becomes 'skeleton' (I've seen this before).
'of what' becomes 's' (I can't justify this - if you can you should give a lot more credence to this answer).
'skeleton'+'s'='SKELETONS'
Can you help me to learn more?
(Other definitions for skeletons that I've seen before include "Body frames" , "Frameworks of bone" , "Lost knees (anag.)" , "Bony frameworks" , "Frames of bodies" .)