Majungatholus Atopus: A Dinosaur Cannibal:: 2 Works Cited
Length: 1223 words (3.5 double-spaced pages)
The dinosaur Majungatholus atopus is a meat-eating dinosaur that lived 65 to 70 million years ago, during the Cretaceous period, in what is now the island of Madagascar. The Majungatholus has long been known for being a carnivorous dinosaur, but it wasn’t until recently that researchers revealed that this dinosaur was probably a cannibal. They were able to conclude that this was probably the case as a result of discovering several bones of the Majungatholus dinosaur with specific tooth marks in them that researchers have proven belonged to the Majungatholus dinosaur. In her 2003 press release for the National Science Foundation (NSF), Cheryl Dybas quoted the NSF program director Richard Lane, “this research greatly expands our understanding of how dinosaur species related to each other in the context of their environment, and also serves as a way of increasing public awareness of and appreciation for the earth sciences."1
There was one other discovery of what might have been another cannibal dinosaur; the Coelophysis bauri, a small Triassic theropod2, this discovery however has not yet been proven and may be unconfirmed. The discovery of the Majungatholus however has what geologist Raymond Rogers calls the “smoking gun in the form of diagnostic tooth marks,” which are “a ‘snapshot’ of a day in the life-- and death—of Majungatholus.”3 There is however no evidence to point to whether or not Majungatholus killed its meals or simply scavenged.
Rogers says the evidence for the theory of cannibalism comes from twenty-one tooth marked elements which were a part of two different Majungatholus individuals found in two isolated locations on the island of Madagascar.4 On these bones are distinct sets of tooth marks that point only to being from the jaws of a Majungatholus dinosaur; the marks not only match the size and spacing of the teeth found in the jaws of the Majungatholus, but they also have the same smaller grooves that match the sharp irregularities of this particular dinosaur. According to Rogers, “measurements taken from the modified bones and the Majungatholus teeth are comparable.”5 The set of parallel tooth marks found on one of the bones matched up with the same approximate inter-tooth spacing as the jaw of the Majungatholus. This particular dinosaur also can display an even pattern of tooth eruption that is evident in several of the bones in the sample.
Rogers and his colleagues still took no chances in trying to rule out any other potential dinosaurs or related individuals, which might have left similar tooth marks on the fossilized bones. In order to rule out this possibility concretely, Rogers examined the “jaws and teeth of other known meat-eaters in the Malagasy fauna, including a much smaller carnivorous dinosaur called Masiakasaurus knopfleri, and two large crocodiles.”6 The small size of the only other known theropod from the region, Masiakasaurus knofleri eliminates it from having been able to leave the tooth marks found on the bones, which were definitely from a larger dinosaur. The early forms of the crocodiles were also ruled out because, “their robust, conical teeth were too blunt, too irregularly spaced, too variable in height, too variable in orientation and too variably positioned” to be have caused the narrow U shaped grooves found in the bones.7 After all of this research and examination, Rogers and his associates concluded that only the Majungatholus had the jaws and teeth capable of inflicting the damage they saw on the fossilized bones they had discovered. This, along with the data from three separate bone-beds that points to Majungatholus regularly de-fleshing carcasses shows that this dinosaur is the closest researchers have come as of yet to finding cannibalism among dinosaurs.
Rogers was quoted as saying, “despite the bad press that human cannibals receive, this discovery of cannibalism in a theropod dinosaur should come as no big surprise.”8 Cannibalism is a natural tactic that is somewhat common among animals past and present. “At least fourteen species of mammalian carnivores kill and eat members of their own species, and numerous reptilian and avian taxa also practice cannibalism.”9 What makes this discovery important is that previously there had been little to no concrete evidence that cannibalism existed among dinosaurs.
Despite not knowing whether or not Majungatholus actually killed members of its own or simply scavenged meat off of their corpses, this discovery explains a bit about what life was like during the reign of Majungatholus. Rogers says that, “there is a good indication that Majungatholus lived during hard times.”10 From what is known about Madagascar during the Late Cretaceous period, the environment was seasonal and had a semi-arid climate. This was not too different from the environment of Madagascar today. There was also no steady supply of food or water, and this proved to be a problem. It was hard to sustain life with no sure means to gain nourishment, so this period was characterized by mass extinction among animal populations in the area.11 This lack of food might have been what drove Majungatholus to eat its own; it was a source of nutrients during time when resources were hard to find.
It seems as if the evidence both Dybas and Rogers present in their articles is conclusive and thorough. Rogers examined why the toothmarks on the bones match the jaws of the Majungatholus through measurements of the teeth themselves as well as the space between them, the shape of the teeth and any decay patterns they might have had. In addition he ruled out any other carnivores during the time that might have preyed on this particular dinosaur by examining their jaws and teeth and comparing them to the marks left on the bones to see if the imprints or measurements might match. While other theories have been hatched about the possibility of cannibalism among dinosaurs, this is the only one with conclusive evidence to back it up.
Rogers also provides good insights into what might have driven Majungatholus to cannibalism and whether or not this is normal in nature. He comments on the patterns of cannibalism among animals alive now to that, which might have existed during the Late Cretaceous period. This discovery is significant because it is the closest any researcher has come to finding evidence of cannibalism among dinosaurs and with further research, it might provide more information about the climate during this time. Rogers took an interesting path commenting on the harsh conditions in the area where the bones were found and suggesting that Majungatholus might have been driven to cannibalism.
Dybas, Cheryl. “Dinosaur Cannibal Unearthed in Madagascar.” National Science Foundation Press Release 03-36, April 2, 2003. <http://www.nsf.gov/od/lpa/news/03/pr0336.htm>
Rogers, Raymond R, David W. Krause and Kristina Curry Rogers. “Cannibalism in the Madagascan dinosaur Majungatholus atopus.” Nature 422 (3 April 2003): 515-518.
 Dybas, Cheryl. “Dinosaur Cannibal Unearthed in Madagascar.” National Science Foundation Press Release 03-36, April 2, 2003 par. 2.. <http://www.nsf.gov/od/lpa/news/03/pr0336.htm>
 “Which is said to have been found with the remains of juvenile individuals preserved in its stomach region.” Dybas par 7.
 Dybas, par. 7.
 Rogers, Raymond R, David W. Krause and Kristina Curry Rogers. “Cannibalism in the Madagascan dinosaur Majungatholus atopus.” Nature 422 (3 April 2003): 518.
 Rogers, 517.
 Dybas, par 5.
 Rogers, 518.
 Dybas, par 6.
 Rogers, 518.
 Dybas, par 9.
 Dybas, par 9.