Everyone jokes about Tyrannosaurus having small arms; however, abelisaurs take it to an entirely new level.  All while maintaining 4 fingers!  You can see that in the bottom right inset.  The complete hand has been found and, yep, ridiculously tiny.  Look at the super-tiny radius and ulna!  There are no ossified carpals (if you are wondering what is missing). The humerus isn't even the length of the coracoid (part of the shoulder bone).  What in the world were they doing with such tiny arms?  I'm open to suggestions.  They were muscular, so they were likely doing *something* with them, but what?  They may have lacked claws, and the fingers may have been like mittens!  What? Yet, they were highly flexible.  I have this vision of it swirling each tiny nub around in circles while it charged at animals with its missile head loaded with teeth.  One suggestion is the hands were used for mating displays or even during mating, like some boas, who use their vestigial legs to stroke their mate.  

 

The only large herbivores that it lived amongst were titanosaurs.  It has been suggested this animal was a sauropod specialist, using its stout, robust, broad skull with a powerful bite to take down a sauropod.  It would bite, use its massively strong neck to rip backward, and take out a huge chunk of flesh.  Notice its legs aren't long, this animal was likely an ambush predator.  A burst of speed from the treeline, bam, it is on a smaller sauropod, rending huge quantities of flesh.

 

Or did it use such powerful bites to strip the flesh off of dead, dry animals?  Spending most of its time as a scavenger?  This blends into the proposed cannibalism as 2 specimens (FMNH PR2100, UA 8678) were found with bite marks on ribs and vertebrae that clearly came from other Majungasaurus.  I love the line in the paper Majungasaurus: "...regularly defleshed dinosaur carcasses."