Geoscience Reference
In-Depth Information
Meet the bowerbirds of Australia and New Guinea. Sometimes nicknamed the
“amorous architects,” male bowerbirds build a variety of structures—bowers—that
are intended to catch the eye of a prospective female. Bowers are placed into three
basic categories: mats, maypoles, and avenues. Mats are like ground canvases ad-
orned with meticulously placed leaves, stones, shells, or even beetle wings. May-
poles are vertical structures, composed largely of sticks arranged around a small
tree, but can also resemble teepees. Avenues, which consist of parallel walls made
of leaves, sticks, and flowers, leading to a nuptial meeting spot, seem like run-
ways that lead to a heart-shaped bed at their ends. The intricacy of most bowers
is astounding, and may include shiny human-made objects such as items made of
glass, metal, or plastic. Some bowerbirds even use perspective in their handiwork,
placingsmallerpiecesofglassorrocksatthefrontofabowerandlargerbitstoward
the rear: the only examples of such artistic renderings known outside of humans.
For further enticement, in an attempt to seal the deal, bowerbirds usually throw in a
dance or two.
Sadly, like stick nests, these monuments to mating have extremely low preser-
vation potential in the fossil record. Besides, an exquisitely arranged collection of
leaves, flowers, and sticks will probably not retain its original integrity after weath-
ering, erosion, and burial for it to be interpretable as a bower; however, it might
excite paleobotanists. The bowers most likely to be recognized as trace fossils are
those in which their makers used rock or shell collections. After all, a large group-
ing of perfectly identically sized and shaped stones (and ones that clearly are not
gastroliths), along with snail shells and beetle wings, should catch the attention of
a paleontologist encountering these in the geologic record, especially if associated
with a dinosaur skeleton, or (even better) two of the same species.
Fortunately, a lack of evidence for Mesozoic bowers did not stop the imagin-
ations of screenwriters and computer-graphics artists for the Discovery Channel, in
the TV series
Dinosaur Revolution
(2011), from recreating a Cretaceous scene in-
spired by bowerbirds. This scene starred a computer-generated image of the large
