Animal Architects: Building and the Evolution of Intelligence

Article excerpt

Animal Architects: Building and the Evolution of Intelligence by James L. Gould and Carol Grant Gould, Basic Books, 2007; $26.95

Consider the Steel and glass towers Wof Dubai or Singapore, the spare elegance of Frank Lloyd Wright's Fallingwater, or the convoluted curves of Frank Gehry's Guggenheim Museum in Bilbao, Spain. Consider even the most mundane big-box store, for that matter, and it is clear that we humans are master builders, able to create artificial environments orders of magnitude larger and far more elaborate than those of any other species on earth.

Still, the architectural achievements of other creatures are nothing to sniff at, as the ecologist James Gould of Princeton University and the science writer Carol Grant Gould amply demonstrate in their stimulating study. Beavers, the most familiar animal builders, exhibit levels of engineering and organization that might challenge the Army Corps of Engineers. L.H. Morgan, an amateur naturalist who studied beaver dams near Lake Superior in the 1860s, described one that was 261 feet long, 6.5 feet high, and eighteen feet thick at its base. It was made up of tree trunks, limbs, branches, and stones, cemented together by vast amounts of mud and braced by sharpened stakes driven vertically into the ground. And if that sounds impressive, consider the mother of all recorded beaver dams, on Montana's Jefferson River, which stretched nearly ten times farther-2,200 feet-from end to end.

If brain mass were correlated with architectural skill, one would expect most animal architects to be mammals. The truth is quite the reverse. Most mammals are content to sleep outdoors, use existing caves as dens, or at most, dig. The real masters of the building arts are birds and insects, whose nests and hives display an uncanny ingenuity in both design and creation.

Weaverbirds, for instance, natives to Africa, India, and Southeast Asia, not only weave, but seem to understand knots as well. Male weaverbirds begin construction by looping a thin strip of leaf or grass over a tree branch, then securing it by tying a knot. The bird suspends its nest from this secured strip, interweaving more strips of vegetation until it has stitched together a large ovoid dwelling, resembling a giant ball of twine. …