Geoscience Reference
In-Depth Information
ofshortflights, suchasthe Late Jurassic
Anchiornis
orEarly Cretaceous
Microrap-
tor
, and thus could have made hopping or skipping tracks to get themselves aloft.
In a 2013 study, paleontologists using CT scans of non-avian and avian thero-
pod skulls (including that of
Archaeopteryx
) suggested that some non-avian dino-
saurs had brains well suited for the complexities of flight, with a few better than
Archaeopteryx
. Based on other anatomical traits, like long fingers with claws, other
small feathered theropods, such as the Late Jurassic
Scansoriopteryx
(
Epidendro-
saurus
)and
Epidexipteryx
ofChina,lookliketheywerebetteradaptedforclimbing
trees and hanging on branches than being on the ground. This means a better
place to look for their trace fossils might be on petrified logs in same-aged strata,
or at least sedimentary rocks that originally formed near forests. However, a few
feathered theropods were far too big to have either flown or climbed trees, such as
the Early Cretaceous
Yutyrannus huali
, which was close to 9 m (30 ft) long and
weighed more than a ton. For such weighty theropods, there was no hopping, skip-
ping, jumping, or tree climbing, unless they did these as small tykes.
Thus it might behoove paleontologists who are interested in learning more
about the origins of bird flight to pay attention to flying tracks associated with
modern birds. After all, a continuing controversy in dinosaur paleontology—a real
one, not a fake one like the old “Was
Tyrannosaurus
a predator or scavenger?” ar-
gument—was how self-powered flight evolved in non-avian theropods. Granted,
nobody denies that self-powered flight provided some great advantages for those
dinosaurs. For one, it took them to far more places than running, swimming, or
gliding, but while using less energy than those means of transportation. Moreover,
those places may have offered more choices in food, mates, nest sites, and habitats
for raising offspring. This ability especially came in handy for migrating, in which
these dinosaurs could more easily switch locations with seasonal changes or severe
alterations of local climates. These are big questions that might be helped by look-
ing at little tracks.
