Encyclopedia of Evolution.pdf - Online Reading Center

taxonomy See cladistics; Linnaean system.
technology Technology is the use of tools, which are
objects that are not produced by the body of the animal that
uses them. In a more restricted sense, tools are objects that
have been modified from their natural state before use.
There are numerous examples of animal species using
technology in the broad sense:
• Some birds use sticks to pry insects from holes in trees, and
chimpanzees use sticks to remove termites from nests.
• Chimpanzees use rocks to crack nuts.
• Gorillas have been observed to use sticks to check the
depth of water through which they wade.
Technology in the narrow sense has only developed
within the human lineage.
The first evidence of the primate use of modified tools
is the production of stone tools by Homo Habilis and/or
related species. This was the beginning of the Paleolithic
(“old stone”) Age. The toolmakers, of the Oldowan technology
phase (named for Olduvai Gorge in Tanzania), struck
stones, removing flakes and creating sharp surfaces on one
side of the remaining core (unifacial tools) (see table on page
394). These hominins may have used both the flakes and the
cores as tools. Oldowan tools were also made by early Homo
ergaster and by Asian Homo erectus. Later H. ergaster,
and Homo HeiDelbergensis, made tools by producing finer
flakes, and cores that were modified on two sides (bifacial
tools). The cores of the Acheulean technology phase (named
after St. Achuel, in France) had much more cutting surface
per weight of stone than did the older Oldowan tools (see
table). When H. heidelbergensis evolved into Neandertals,
a more advanced technology phase, the Mousterian (named
after Le Mouster in France) emerged. Mousterian tools had
more cutting surface, and showed more diversity within a set
of tools, than Acheulean tools. Mousterian tools were produced
by the Levallois technique (named after yet another
T
archaeological site in France) in which the toolmaker determined
the general shape of the flake as soon as he or she
removed it from the core, then modified the edge. Mousterian
tools had very limited geographical variability.
Some advanced tools, such as an almost 90,000-yearold
bone harpoon, were made in Africa (see Homo sapiens).
Most anthropologists consider that these inventions occurred
only in H. sapiens. Until about 30,000 years ago, progress in
tool technology occurred slowly. For almost 50,000 years,
Neandertals and H. sapiens coexisted in what is now Israel
and Palestine, and both used Mousterian tools.
Advances in toolmaking occurred in H. sapiens populations
in all parts of the world. What is often called an explosion
of technological invention occurred when H. sapiens
reached Europe. Anthropologists speculate that H. sapiens
developed these tools, along with more art and more complex
social structure, in response to the most recent of the ice
ages as well as to the Neandertals who were already present
in Europe. H. sapiens in Europe went through a succession
of technological phases that was rapid in comparison
to the entire previous history of hominins (see table). Finer
tools, a much more diverse toolkit, and geographical differences
in toolkits resulted. The last Neandertals used a toolkit
that was similar to the Aurignacian tools of H. sapiens. These
Châtelperronian tools may have been copied from H. sapiens,
or stolen from them. The possibility that H. sapiens derived
the ideas for Aurignacian tools from Neandertals cannot be
discounted.
Scientific knowledge of toolmaking is restricted to
stone tools, since bone, wood, and other media decompose.
Wooden spears, made 450,000 years ago by H. heidelbergensis,
have been recovered from deposits where moisture and
lack of oxygen restrict decomposition. H. sapiens used stone
tools during the Mesolithic (“middle stone”) Age, as they
hunted, gathered, and formed more complex social groups.
In the Middle East, they set stone or bone into wooden handles
for harvesting wild grains. H. sapiens continued using