Geoscience Reference
In-Depth Information
feathered theropod
Gigantoraptor
, an oviraptorosaur from the Late Cretaceous (70
mya
) of Mongolia. In it, a male with gaudily colored feathers, as well as a bright
blue-and-red wattle (reminiscent of a cassowary), had cleared out a shallow cir-
cular depressionandlined it with sticks and stones. Once a more drably colored
(yet comely) female
Gigantoraptor
approached with some interest in what he had
to offer, he commenced showing off his wattle and feathers and began to dance
within the bower-like structure. (Amusingly enough, the dance was scored with a
flamenco-like piece of music, underlining its seductive qualities.) As an added ich-
nological bonus, a small-mammal burrow complex was under the bower, with its
mammals increasingly disturbed by the commotion above.
Unfortunately for both the male
Gigantoraptor
and the mammals, the bower
soon collapsed under the weight of the dancing
Gigantoraptor
; this was not a sur-
prising development, as these dinosaurs weighed about 1.5 tons, or ten times as
much as an adult cassowary. This accident brought his performance to an embar-
rassing end, and his love interest quickly retreated, presumably to find a mate with
better bower-building abilities. So not only did he not get the girl theropod, but he
also ended up being a home wrecker.
Given this basic knowledge about modern bird courtship traces and what to
look for, a huge advantage of interpreting trace fossils of these is that they are
tied to gender; few trace fossils, other than some insect and sea-turtle nests, allow
for such specificity. Thus, I have a dream that some day kinky-minded paleonto-
logists—which is to say, virtually all paleontologists—will recognize the fossilized
remainsoftheropodorbirdcourtshiptracks,amplifiers,bowers,orothersuchwoo-
ing traces.
Dust Baths, Sun Baths, and Other Traces of Dirty Birds
Feathers require maintenance for several reasons. For one, they provide nice hiding
places for skin parasites or other microbiota that might like to hang out underneath
them. For another, birds have glands that secrete oil onto their feathers, an espe-
cially important accessory for birds as a form of waterproofing. This means that
