microchiroptera and megachiroptera

It is a matter of great debate between scientists whether bats in the different suborders (micro and megachiroptera) had a common ancestor. There is evidence for both sides of the argument.

Megachiroptera Microchiroptera
don’t hibernate many hibernate
complex visual system less complex visual system
only 1 species uses sonar (in the form of tongue clicks) use sonar (laryngeal sound)
no tragus tragus
no facial ornamentation facial ornamentation
claw on 2nd digit in most no claw on 2nd digit
unmodified cervical vertebrae,
ventral head posture
modified cervical vertebrae,
dorsal head posture
(enables them to bend their necks backwards, so that they can hang straight down in a roost and arch their heads back to look around)
no tail/uropatagium (usually) tail and uropatagium (usually)
large body/eyes small body/eyes
short or absent angular process on dentary long narrow angular process on dentary
well-developed post orbital process post orbital process generally absent
palate extends beyond last upper molar Palate not extending past last upper molar
low, quadritubercular flat molars without W-shape specialised for crushing fruit Sharp, W-shaped cusp that can shear and crush food