SKULL AND BONES
IN 200,000 YEARS WE'LL BE FOSSILIZED BITS TO PONDER
Are we, Homo sapiens
sapiens (wise wise man?), the culmination of the 5 million
years of human evolution, or a
step along the way to something else, to Homo
sapiens futuristis? Two hundred thousand
years ago, Neanderthals--technically
Homo sapiens neanderthalensis--were the dominant human
life on Earth. What kind
of people will the earth see 200,000 years from now?
Fifteen years
ago, when I first started researching for The Clan of the Cave
Bear, the earliest known
appearance of modern humans was in Europe around 40,000
years ago, during the last ice age.
They were the ones referred to as
Cro-Magnons, and there was evidence that for a period of
time, they lived side
by side with Neanderthals,
The case for their coexistence has now
become much stronger. The skeleton of a
Neanderthal was found in France that dates to
around 30,000 years ago,
demonstrating that western Europe was home to both for perhaps
10,000 years, but
even more astonishing are discoveries from the rest of the world. New
techniques
have dated the bones of an anatomically modern man discovered in Israel as
90,000
years old. There is still some doubt about the dating method, but if the
date holds it
means that both modern and Neanderthaloid types of humans occupied
that part of the world
for 60,000 years!
When did these two subspecies of Homo sapiens emerge? Around a million
and a
half years ago in Africa, an earlier form of hominid, Homo erectus, began
migrating
and eventually populated the rest of the Old World. Neanderthal types
that have been found
throughout Africa and Eurasia apparently evolved directly
from the local H. erectus. In
France, for example, there are erectus sites such
as Tautavel that date back 400,000 years,
and the recently excavated Grotte
Vaufrey that date Neanderthals at about 300,000 years.
At one time most archaeologists thought that modern humans, H. sap. sapiens,
evolved in
Europe from H. sap. neanderthalensis, but new evidence suggested that
we arrived later,
bringing with us a more developed stone tool kit. It was then
theorized that at some
unknown location, east or south, modern humans evolved
from an earlier type, perhaps H.
erectus, and migrated to Europe.
Then, a few years ago, DNA studies indicated that
anatomically modern humans
could be traced back to an original mother, dubbed Eve, though
it may have been
a group of related women who evolved, again in Africa, less than 200,000
years
ago. Those early modern humans are thought to have migrated to all the rest of
the
world, completely replacing the existing populations.
That theory has been disputed by some
paleoanthropologists who have examined
skulls of earlier forms, such as H. erectus,
particularly in Asia, and found
indications of characteristics still seen in Oriental
people today. How could
the newcomers replace existing populations but take on their
physical traits?
Could there have been some intermixing? In central Europe and the Mideast,
a
combination of Neanderthal and modern human characteristics is sometimes found
in a single
skull, but scientists debate whether it shows evolution or
crossbreeding.
Debates are the
heart of the scientific process, but looking at the past can
shed light on the future. The
evidence suggests that evolution is still going
on, but what lies ahead? Drastic climatic
changes probably played a major role
in the adaptive strategies of ancestral hominids, but
mutational changes occur
at different rates and contemporary societies have so much
control of their
physical environment, they can live in any climate, including no climate
at all,
in space. Will that lessen the selective pressures to change and cause the
process
of evolution to slow?
Or will the pollution, the chemical fertilizers and pesticides, the
toxic and
nuclear wastes, the greenhouse effect, and the depletion of the ozone layer
accelerate
mutations? What about reactor meltdowns? Nuclear winter? Nuclear war?
Though most would be
harmful or fatal, might some mutations actually be
beneficial? Perhaps selecting for
immunity from some of the effects? What about
genetic engineering?
There are no more
Neanderthals, but are there still a few Neanderthal genes?
Were they replaced or
assimilated? Would we share our world with another kind of
intelligent human being? One
that might make us the next Neanderthals? The
thought is fascinating to consider. One
could even imagine stories...