Infant megalodons were around 3.5 meters ( 11 ft ) at their smallest .
The pups were vulnerable to predation by other shark species , such as the great hammerhead shark ( Sphyrna mokarran ) and the snaggletooth shark ( Hemipristis serra ) .
Infant megalodons were around 3.5 meters ( 11 ft ) at their smallest , and the pups were vulnerable to predation by other shark species , such as the great hammerhead shark ( Sphyrna mokarran ) and the snaggletooth shark ( Hemipristis serra ) .