Sot upset intense African creature (7)

I believe the answer is:

ostrich

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'creature' is the definition.
(ostrich is a kind of creature)

'sot upset intense african' is the wordplay.
'upset' indicates an anagram.
'intense african' becomes 'rich' (I can't justify this - if you can you should give a lot more credence to this answer).
'sot' anagrammed gives 'ost'.
'ost'+'rich'='OSTRICH'

Can you help me to learn more?

(Other definitions for ostrich that I've seen before include "The head-in-the-sand bird" , "A bird for the shirt co." , "non-flyer?" , "Denier" , "Runner" .)

I've seen this clue in The Sun.

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