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stance, if
Triceratops
horns ever did pierce tyrannosaur skin, we have no record of
it.
Tyrannosaurus
skin impressions are thus far unknown, and even if such spectac-
ularfindsareuncovered,thesemayormaynothaverecordedanywounds,letalone
ones attributable to
Triceratops
. One would also think that the force generated by a
jousting
Triceratops
would have left distinctive marks on tyrannosaur leg bones or
other skeletal parts, but these are likewise unidentified.
Only one tantalizing
Triceratops
skull tells of a living battle with a
Tyranno-
saurus
, in which one of its brow horns and a squamosal bone were chomped and
later healed. But this evidence is just enough to provoke far too many questions.
Who started the fight, the tyrannosaur or ceratopsian? Was this an argument over
food—as in, the
Triceratops
was potentially food for the tyrannosaur, but objec-
ted—or was it over territory, in which one of two powerful animals needed more
space?Andofcourse,whoendedthefight?Didthetyrannosaurwalkawaywithno
injuries, some injuries, or worse? All we know is that the
Triceratops
survived this
testy encounter. Otherwise, without the trace fossils so helpfully left by a
Tyranno-
saurus
on a
Triceratops
skull, we might not have known about it at all.
Lackinganyclearevidencethathornswereusedasimplementsofself-defense
against large theropods, paleontologists turned away from violence and reached
for sex. That is,
Triceratops
horns combined with head shields are now regarded
more as sexual advertisements than battle gear. In this role, their large heads would
have been quite useful for recognizing the same species and perhaps gender, thus
neatlyavoidingtwoegregiousmistakessometimesmadewhenevertheurgetomate
takesovernearlyallreason.Moreover,oncetheseceratopsianscorrectlyrecognized
the same species and opposite gender in another ceratopsian, these horns and head
shieldsthenmayhaveservedasecondoverlappingpurposeasimplementsforcom-
bat. These contests most likely would have been over mates, but also could have
beeninspiredbyaneedformoreterritory,scarce foodandwaterresources,protect-
ingyoung,oranill-temperedceratopsiansimplydecidingtotakeoutitsfrustrations
onanother.Asaresult,collidingheadsandpiercinghornslefttheirmarksashealed
