Assertion: tropic bird's wing | /r/CapableOf | lend speed
Facets:
value: to the evolution of flightlessness
type: TRANSITIVE-OBJECT
Source sentences:
text: Rails have relatively shortened wings to begin with, which in combination with their terrestrial habits and behavioral flightlessness, lends speed to the evolution of flightlessness, making it remarkably fast; as few as 125,000 years were needed for the Laysan rail to lose the power of flight and evolve the reduced, stubby wings only useful to keep balance when running quickly.