It was expected that we would discover a number of hominid species
and that is now clarified here. Yet is is also worth recalling that
unique geological circumstances have given us a window into the past
that is generally missing most everywhere else. With three
successful species in just this window the presumption is that all of
Africa at least was well populated with primates.
It has also been convincingly argued that humanity rising overran or
inter married with all other primates besides themselves. Yet it is
reasonable that those populations were never large at all. Small
populations can survive by simple avoidance and specialization in a
different biological niche. Thus we have come to understand the
Sasquatch and its obvious relatives in Asia.
Could a range of different small hominids also exist? So long as
they stay out of our niche, it is certainly possible. If we have had
difficulty in working with the Sasquatch, then this would be a much
larger challenge and we have certainly had difficulty.
It is not particularly obvious that small hominids would share our
ecological niche and that is necessary for rising humanity to hunt
them out into extinction.
If we presume instead that they are skilled forest dwellers and
nocturnal hunters as well ,then the chance for mutual contact
approaches zero and general avoidance is easy.
We do have cultural evidence that has been dismissed for centuries
but still makes the point. They are always small and manlike. I
have even posted on at least one conforming sighting.
The fact that there is little in the fossil record also misstates the
fossil record. There is far too little fossil record at all. We
have almost nothing between the West African fossil window and now.
All we really know is what was possible.
Kenyan fossil find:
The KNM-ER 1470 cranium, discovered in 1972, combined with the new
lower jaw KNM-ER 60000; both are thought to belong to the same
species. The lower jaw is shown as a photographic reconstruction, and
the cranium is based on a computed tomography scan. (Credit: © Photo
by Fred Spoor)
ScienceDaily (Aug. 8,
2012) — Exciting new fossils discovered east of Lake Turkana
confirm that there were two additional species of our genus
-- Homo -- living alongside our direct human ancestral
species,Homo erectus, almost two million years ago. The finds,
announced in the scientific journal Nature on August 9th, include a
face, a remarkably complete lower jaw, and part of a second lower
jaw.
They were uncovered
between 2007 and 2009 by the Koobi Fora Research Project (KFRP), led
by Meave and Louise Leakey. KFRP's fieldwork was facilitated by the
Turkana Basin Institute (TBI), and supported by the National
Geographic Society, which has funded the KFRP since 1968.
Four decades ago, the
KFRP discovered the enigmatic fossil known as KNM-ER 1470 (or "1470"
for short). This skull, readily distinguished by its large brain size
and long flat face, ignited a longstanding debate about just how many
different species of early Homo lived alongside Homo erectus during
the Pleistocene epoch. 1470's unusual morphology was attributed by
some scientists to sexual differences and natural degrees of
variation within a single species, whereas others interpreted the
fossil as evidence of a separate species.
This decades-old
dilemma has endured for two reasons. First, comparisons with other
fossils have been limited due to the fact that 1470's remains do not
include its teeth or lower jaw. Second, no other fossil skull has
mirrored 1470's flat and long face, leaving in doubt just how
representative these characteristics are. The new fossils address
both issues.
"For the past 40
years we have looked long and hard in the vast expanse of sediments
around Lake Turkana for fossils that confirm the unique features of
1470's face and show us what its teeth and lower jaw would have
looked like," says Meave Leakey, co-leader of the KFRP and a
National Geographic Explorer-in-Residence. "At last we have some
answers."
"Combined, the
three new fossils give a much clearer picture of what 1470 looked
like," says Fred Spoor, leader of the scientific analyses. "As
a result, it is now clear that two species of early Homo
lived alongside Homo erectus. The new fossils will greatly help
in unraveling how our branch of human evolution first emerged and
flourished almost two million years ago."
Found within a radius
of just over 10 km from 1470's location, the three new fossils are
dated between 1.78 million and 1.95 million years old. The face
KNM-ER 62000, discovered by field crew member Elgite Lokorimudang in
2008, is very similar to that of 1470, showing that the latter is not
a single "odd one out" individual. Moreover, the face's
well-preserved upper jaw has almost all of its cheek teeth still in
place, which for the first time makes it possible to infer the type
of lower jaw that would have fitted 1470. A particularly good match
can be found in the other two new fossils, the lower jaw KNM-ER
60000, found by Cyprian Nyete in 2009, and part of another lower jaw,
KNM-ER 62003, found by Robert Moru in 2007. KNM-ER 60000 stands out
as the most complete lower jaw of an early member of the genus Homo
yet discovered.
The team working on
the new finds included Christopher Kiarie (TBI), who carried out the
laboratory preparation of the fossils, Craig Feibel (Rutgers
University), who studied the age of the fossils, and Susan Antón
(New York University), Christopher Dean (UCL, University College
London), Meave and Louise Leakey (TBI, Kenya; and Stony Brook
University, New York) and Fred Spoor (Max Planck Institute for
Evolutionary Anthropology, Leipzig and UCL), who analyzed the
fossils. The National Geographic Society funded the fieldwork, the
Leaky Foundation funded geological studies, and the Max Planck
Society supported laboratory work.
TBI is a privately
funded, non-profit initiative founded by Richard Leakey and Stony
Brook University, New York, that seeks to facilitate
multi-disciplinary fieldwork within the Lake Turkana Basin in
affiliation with the National Museums of Kenya. The primary research
focus is human prehistory and related earth and natural science
studies. For more information, visit TBI at:
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