The majority of rodent species are considered as pests of agricultural crops, range lands and forests (Khan, 2012) and not as being considered worthy of conservation except few species of Jarbos (Saltpingotus michaelis and Allactaga elator) and
crestless Himalayen porcupine, Hystrix hodgsoni.
The Makushi use the black wing feathers of the
crestless curassow to fletch their arrows.
Fossils discovered together with an egg in Jurassic rocks (about 160 million years old) in China show that females were
crestless, solving the long-standing problem of what some pterosaurs did with their spectacular head crests: showy displays by males.