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their rear feet, with four total. Unfortunately, the skeleton of
Panphagia
did not in-
clude its foot bones, so we don't know for sure the forms of its tracks or those of its
relatives at the time.
Using this combination of skeletal data and knowing that evolution often pre-
cededtheoldestpreservedfossils,paleontologistsfigurethatdinosaursactuallyori-
ginated at around 235
mya
, toward the end of the Middle Triassic Period. Sure
enough, three- and four-toed tracks similar to those predicted for primitive dino-
saurs are fairly common in some Middle Triassic rocks. Because these tracks were
sosimilartothoseofknowndinosaurtracks,theirdiscoverersexcitedlypronounced
them as “dinosaur-like” and hinted that these footprints extended dinosaur lineages
to well before their skeletal record. Unfortunately, such claims were thoroughly
trounced, flogged, ridiculed, and otherwise treated as unworthy of any encourage-
ment whatsoever. The bulk of this disdain, of course, came from paleontologists
whostudieddinosaurbones,nottracks.Asaresult,advocatesoftracefossileviden-
ce for dinosaur ancestry were stymied, as they also somehow had to connect tracks
to feet foretold—but not yet found—for animals that heralded the arrival of true di-
nosaurs in the Late Triassic Period.
Some of this disrespect for all things ichnological was allayed in 2010 when
a team of paleontologists, led by Stephen Brussatte, published a paper in which
they proposed the oldest “dinosauromorph” tracks from the fossil record.
Dino-
sauromorph
refers to the clade Dinosauromorpha, which includes all animals more
closely related to dinosaurs than other non-dinosaurs, such as pterosaurs and cro-
codilians. This means that ancestral dinosauromorph tracks almost look like dino-
saur tracks, but not quite: sort of how a primitive human's tracks would differ from
those of a same-sized modern human. Some of these tracks, which were from Early
Triassic(about245
mya
)rocksinPoland,precede
Eoraptor
bymorethan15million
years. These paleontologists also pointed out, somewhat indignantly, that “… foot-
prints are often ignored or largely dismissed by workers focusing on body fossils,
and are rarely marshaled as evidence in macroevolutionary studies of the dinosaur
