of these variations, all chimpanzees build nests each night. The primatologist W.C. McGrew writes, “There is nothing more predictable in chimpanzee daily life than this universal behavioral sequence and its artifactual outcome. It is the cornerstone of chimpanzee nature.”12
Since they are imposing animals, gorillas worry less about predators—except for human poachers—and their homes reflect this nonchalance.13 Given their large bulk, gorillas tend to nest on the ground, although occasionally they nest in trees. The primatologist Dian Fossey described their nests as “sturdy, compact structures, sometimes resembling oval, leafy bathtubs.”14 The mountain gorilla, as the biologist George Schaller documented, “stands or sits, and pulls, breaks, or bends in vegetation which it places around and under its body.” Regardless of their basic construction technique, “the precise method employed varies with the particular circumstance—whether the nest is in a tree or on the ground, whether it is on a steep slope or a flat area.”15 Similar to the chimpanzees, gorillas apparently reoccupy nests only when abundant fruits or other foods tempt them to stay in an area.16
In less than five minutes, a gorilla can make a treetop nest, bending down the branches in a tree’s crown or weaving limbs into a platform bed. Ground-level nests take even less time, built from a few handfuls of foliage roughly arranged in less than thirty seconds.17
But what are the functions of the nests built by chimpanzees, bonobos, and gorillas?
There are several possible answers.18 Arboreal nests may protect sleeping primates from predators, although various monkeys sleep in trees without building nests. Sleeping in treetops may protect primates from mosquitoes and other biting insects that transmit diseases. One of the strongest explanations links nest building and body heat, the “thermoregulation hypothesis,” because the differences appear linked to local environment and weather. Unlike other animals—whose constructions are uniform, presumably because those behaviors are genetically hardwired—higher apes appear to have a basic drive to nest, but vary their constructions based on local circumstances. As the authors of one study of gorillas living in the Congo put it, the variations in nests “appear to be in response to wet and cool conditions, clearly suggesting that the gorillas call on innate nest-building tendencies with a quite flexible, adaptive specificity.”19
These findings suggest that the nests built by African apes differ from other examples of animal architecture in one fundamental regard: the constructions vary in response to local conditions. While we recognize that modern apes are not our hominid ancestors, it is interesting to realize that, like these primate relatives, all humans make shelters but do so in different ways. It may be that this common adaptive propensity is the essential connection. Despite the variations and differences between ape nests and human dwellings, there exists this broad connection, leading one primatologist to ask, “Was there no place like home?”20
. . .
As of this writing, the oldest home I have excavated is merely 6,000 years old. In June and July of 2006, I directed excavations in far northern Peru at a small prehistoric site called El Porvenir. I had first seen the site in 1996 during an archaeological reconnaissance near the border between Peru and Ecuador; it had taken ten years to raise the funds to return and excavate the site (not an uncommon occurrence in archaeology).
El Porvenir caught my attention and drew me back a decade later because I thought it would contain evidence of ancient homes. The site consisted of a group of six earthen mounds around an open space, which I assumed was a cluster of house mounds around a central plaza. El Porvenir covered an area a bit larger than a football field, 120 × 90 meters. The mounds were simple ovals, 10 to 30 meters at their bases, and the tallest mound was only 1.6 meters tall. The mounds were noticeable, but not impressive. What these surface details suggested was this: these were not monumental constructions or carefully built public architecture, but rather simple mounds probably containing archaeological evidence of ancient dwellings and households. And that is why I excavated El Porvenir.
On the surface of the site, we found a few stray burnished brick-red potsherds decorated with lines and dots of a creamy white. Based on what we knew in 2006, we thought this pottery style dated sometime between 500 B.C. and A.D. 500 (the vagueness of the date simply reflecting how little we understood of the region’s prehistory). Since the El Porvenir mounds were relatively small (these were not massive accumulations like Near Eastern tells) I expected that even the oldest layers of El Porvenir would date sometime within the 500 B.C. to A.D. 500 range or perhaps a few centuries older—but not by much.
I was very wrong.
We began excavating the mounds of El Porvenir. We laid out 2 × 2 meter test pits arranged in a row to transect the mound, their edges lined by taut staked strings. We scraped through the hard dun clay, and within inches of the surface encountered the first traces of ancient dwellings.
There was not much to see. A few irregular lumps of adobe bricks, fire-reddened and ashy—the remains of a cooking hearth. A harder surface was a floor compacted by footsteps. A right-angled line of postholes penetrated the floor, small divots darkened by the rotted wooden poles that once supported the walls. A cluster of sun-dried clay chunks bore grooved imprints of river canes. From such prosaic traces, we discovered a portion of a roughly rectangular structure built from wattle and daub, and the cooking hearth indicated that we had uncovered an ancient home.
Below this floor was a jumbled stratum of fill, a craze of rubble and shells. The shells were principally of oysters and other mollusks that lived in mangrove swamps now located 6–10 kilometers west of El Porvenir. The clutter of shells, cocked at every angle, was a garbage dump, or midden, rather than the floor of a prehistoric home.
Under the midden layer were the fragments of another earlier house. Later occupants of El Porvenir had dug into and destroyed the lower levels, yet enough remained of the earlier structure to partially reconstruct it. In one corner there was a basin-shaped hearth molded from mud and holding grey ash and charcoal flecks. We found sections of compact floor made from intentionally poured layers of grayish river mud; the grey mud floor was ripped away in places by later trenching, but clearly defined an earlier dwelling. More post-molds were visible in the preserved patches of flooring, arching in a broad curve that indicated an elliptical structure. There were no traces of mud daub, indicating that this earlier house differed in plan and construction from the rectangular wattle and daub house perched above it.
We troweled into even earlier layers. As each stratum was uncovered, all the features were mapped and photographed. The soil was screened to recover the smallest fragments of the past.
We dug through another thick stratum of oyster, removing over 500 kilograms of bone-grey shells. In the same layers we found hundreds of fragile fish bones from catfish, mullet, tuna, sea bass, and other delectable fish. Some species had been netted and hooked in the quiet mangrove estuaries, others taken from boats on the open sea. Small pottery shards and stone flakes sprinkled the shell midden as we dug down in the mound.
And finally we came upon the very oldest house at El Porvenir.
The traces of the house were simply a curved wall marked by small post-molds. The posts had been set in pairs, presumably on both sides of an elliptical wall. Additional posts were set in the middle of the floor, apparently supporting narrow roof-beams that intersected like the spokes of a wheel. We estimated that the structure would have been about five meters in diameter. The floor consisted of a compact layer of dense midden.
When we excavated this floor we thought it was old, but only six months later—after we were able to export samples for radiocarbon dating and obtained the laboratory results—did we know just how old. The samples from the oyster shell layer dated to 4700–4340 B.C. and the floor was older than that—the house was more than 6,000 years old.
