Sentence Correction (SC) | For some birds the sense of smell appears to play a role in navigation

Hiteaserbae

let me try,

For some birds the sense of smell appears(prsent tense) to play a role in navigation, sincepigeons with surgically removed olfactory nerves were found to have increased difficulties in homing.

'with surgically removed olfactory' - is a modifier, modifying 'pigeons' (these are the special pigeons whose olafactory nerves have been removed)

(A)were found to
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