Geoscience Reference
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they examined
T. rex
bones in museum collections at the University of California
(Berkeley)andtheMuseumoftheRockies(Montana)andrealizedthatnotonlydid
some of these bones have toothmarks, but big ones. Even before measuring these
marks, the paleontologists knew that their depths, lengths, and spacing between
teeth limited them to the largest land carnivore that lived at the same time as
T. rex
,
which would have been
T. rex
. Unexpectedly, bones from four separate specimens
held these toothmarks. Considering the rarity of
T. rex
specimens in general, and
to have four with toothmarks also coming from
T. rex
, cannibalism in that species
might have been more common than originally thought. Still, such acts might have
beendoneindesperation,asthreeoftheaffectedboneswerefromfeet,andonewas
ahumerus.Let'sjustsaythatifyouweretheworld'slargestlandcarnivoreandyou
were resorting to not only eating your own species but also the least meaty parts,
you were much too hungry. Also, no reasonable person can imagine a live tyranno-
saurquiescentlyacceptinganothertyrannosaurstrippingfleshfromitstoesorarms.
Inotherwords,aprone,deadtyrannosaurwouldhavemadeforamucheasiersnack
for one of its kin.
Trace fossils also tell us that big theropods chewed on one another's faces, but
whiletheirfaceswerestillalive.Thisidea,firstproposedbypaleontologistsDarren
Tanke and Phil Currie in 1998, was based on healed bite marks they noted in skulls
of
Sinraptor
(a Late Jurassic theropod from China),
Albertosaurus
,
Daspletosaur-
us
,and
Gorgosaurus
(allLateCretaceoustyrannosaursfromCanada).Interestingly,
some of this unruly face-biting happened while these theropods were still relatively
young. For example, subadults of
Albertosaurus
and
Gorgosaurus
have face bite
marks,asdidanotherunidentifiedtyrannosaurfromtheLateCretaceousHellCreek
Formation of Montana that got its nose out of joint (literally) caused by a bite to its
nasal and maxilla that bent its face to the left. Because these wounds healed, these
wereprobablyfromcompetitionorterritorialaggressionanddonotreallyqualifyas
cannibalism. Although, considering that these were adolescent dinosaurs, pre-mat-
ing “love bites” cannot be discounted, either. If so, these were hickeys from hell.
