‘In Australia, for example, marsupial herbivores the size of a rhinoceros, kangaroos nearly 10 feet tall, and carnivorous lion-like forms with shearing teeth and retractile claws all roamed the landscape.’
‘Like scaphopods, bivalves have a retractile foot which they use to burrow.’
‘The morphology of the middle and distal phalanx in Tapocyon exhibits a retractile claw condition, supporting this as the primitive condition for Carnivora / Carnivoramorpha.’
‘The habit of felids to use primarily their forelimbs to capture prey is supported by the anatomy and function of their retractile claws.’
‘The feeding zooids use retractile tentacles, called the lophophore, to filter feed and have a U-shaped gut for digestion.’
Origin
Late 18th century from retract, on the pattern of contractile.
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