These drawings show the left arm of a typical small Yumbrabaul still capable of flight.  Note the heavily muscled area near the shoulder, especially where the wing juts out from the arm.  A larger Yumbrabaul would have more densely muscled arms while the muscle near the wings would atrophy from disuse.  The bones are more hollow in the small Yumbrabaul.  The smaller Yumbrabaul prefer lighter bones which facilitate flight (and hunting of the Khuy Thaough who can fly with their wings), while the larger Yumbrabaul prefer more dense bones that are less likely to break during a fight with a Thaough.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

This drawing shows the skull of a small Yumbrabaul that has not developed antlers.  Particular attention should be paid to the enlarged canine, which is a typical trait of carnivorous species.  Examination of this skull shows us that it probably belonged to a mature Yumbrabaul still capable of flight.  Juvenile Yumbrabaul do not develop the enlarged canine, and had this skull belonged to a large Yumbrabaul it would have probably had antlers for defense.  The enlarged ethnoid, or ocular cavity, has evolved in order to provide the Yumbrabaul with better vision to spot both predators and prey.
 
 
 
 
 
 
 
 
 
 

The Yumbrabaul reproduce by laying eggs.  A female will usually lay between one and three eggs.  After an average time of 4 months the young hatch and are cared for by both parents with the aid of the whole pack.  The young Yumbrabaul breast feed for 5 months before they begin to eat solid food.  The small Yumbrabaul will not taste a Khuy Thaough until they are able to catch one.  The large Yumbrabaul will not taste a Khuy Thaough until they have helped defend the pack from an attack by the Thaough.  This could be because the adults are loath to part with their favorite food.  If the Yumbrabaul are sentient it could be that they do not want to hinder the physical development of their young by over stimulating them with dopamine.
 
 
 
 
 
 
 
 
 
 

The Yumbrabaul all have; fur covering their bodies, a prehensile tail, claws, enlarged ethnoids, and enlarged canines.  All mature Yumbrabaul have antlers to some extent although the large Yumbrabaul have much more extensive antlers with many more points.

The ultimate question is "Are the Yumbrabaul sentient?"  If they are sentient then they own the rights to their planet and their permission must be attained before any minerals can be mined or anyone can settle on the planet.  Click here for the latest findings on whether or not the Yumbrabaul are sentient.

This is a photo of a spider monkey using its prehensile tail to hold onto a tree branch.  Prehensile tails are used both for balance and grasping.  They are normally found in tree dwelling creatures.