‘Out of Africa’ theory going out of style?
by Daniel Anderson
Published: 2 May 2007 (GMT+10)
Photo by Erik Trinkaus
A mandible from a skeleton found in China (Tianyuan
Cave, Zhoukoudian, near Beijing City).
The skeletal remains of an early modern human have cast doubt on the popular ‘Out
of Africa’ evolutionary model of human origins.1
Dated at ‘38,500 to 42,000’ years old on the evolutionary time line,
the ancient human fossil was originally discovered in a cave near Beijing, China.
The fossilized remains are claimed to be consistent with an anatomically modern
human, with a mix of archaic characteristics in the teeth and hand bone. Co-author
Erik Trinkaus of Washington University believes this latest fossil provides further
evidence that modern humans interbred with archaic type humans. Incidentally, Trinkaus
also published a study claiming to have identified the fossil remains of a Neandertal/modern
human hybrid in last year’s Proceedings of the National Academy of Science—see
A New Neandertal/Modern
Human Fossil Hybrid? This latest discovery is more welcome news for young
earth creationists! It adds to the evidence that archaic and modern humans are fully
human descendants of Adam and Eve.
Competing origins models
Evolutionists presuppose that humans evolved from ape-like creatures over millions
of years. Based on this presupposition, two competing evolutionary models have emerged.
The more popular ‘Out of Africa’ model hypothesizes that a population
of modern humans spread from sub-Saharan Africa throughout the world tens to hundreds
of thousands of years ago. As they emigrated, they out-competed and replaced the
less fit hominids such as Homo erectus, Neandertal, and ‘archaic’
humans. There would have been little to no interbreeding. The less popular ‘Multiregional
Hypothesis’ theorizes that modern humans evolved in parallel in many regions
of the earth, freely interbreeding with the other human species on occasion.
On the other hand, assuming Genesis is accurate history, creationists presuppose
that the first two humans were specially created on day six of Creation Week about
6,000 years ago. Based on this presupposition, species such as Homo erectus,
Neandertals, archaic humans, and modern humans are simply variations of the same
biblical kind. In other words, they are all fully human descendants of Adam and
Eve, who inhabited various regions throughout the earth after Noah’s Flood
and the dispersion from the Tower of Babel.
Skeletal and genetic variation in humanity
Not everyone is aware that a significant amount of skeletal variation exists in
human beings today. Though evolutionists cling to every little skeletal difference
as evidence that modern humans, archaic humans, Neandertals, and Homo erectus
types were all separate species, all of these differences exist in humanity today—see
Turkana Boy—Getting
past the propaganda. Even several evolutionary paleoanthropologists believe
that Homo erectus, archaic humans, Neandertals, and modern humans all
belong to the same species.2
In addition, there is genetic variation in modern humans. For example, mitochondrial
DNA taken from the remains of an anatomically modern human known as ‘Mungo
Man’ revealed substantial divergence from other modern humans—see Was Adam from Australia?
This discovery has major implications on mtDNA differences between Neandertals and
modern humans. Several Neandertal fossils seemed to suggest significant differences
from modern human mtDNA, and this was offered as clear-cut evidence by ‘Out
of Africa’ evolutionary adherents and progressive creationists that Neandertals
were a separate, subhuman species. However, Mungo Man demonstrates that mtDNA differences
are not the most reliable tool in classifying distinct species. On that same note,
non-human primates can also possess substantially different mtDNA, yet be classified
as the same species.3
Just last year, a new DNA study revealed that a surprising degree of genetic variation
exists in humans alive today.4
In the journal Nature, scientists analyzed the DNA of 270 individuals with
ancestry in Europe, Africa and Asia. To their surprise, scientists discovered large
sections of DNA either entirely missing or duplicated between normal, healthy individuals.
Huntington F. Willard, director of the Institute for Genome Sciences and Policy
at Duke University in Durham, North Carolina, stated ‘The variation among
seemingly “normal” human genomes is quite astonishing.’
the ‘popular’ date can often quickly become ‘out-of-date’ when assumptions
are changed and methods are altered
The genetic findings also suggest that humans and chimpanzees share less DNA similarity
than is commonly touted, although the researchers still consider them to be our
closest evolutionary cousins. This study has major implications for the ongoing
effort of scientists to map the entire Neandertal genome.5 Any small-scale variation should be viewed in light
of the newly discovered variation in the genomes of modern humans living today.
In other words, members of the same species can possess differing degrees of variability
in their nuclear DNA.
Tenuous dating results
Although this latest fossil is dated between 38,500 to 42,000 years old on the evolutionary
scale, these dates are always subject to change. For example, Mungo Man, discovered
by Professor Jim Bowler and Dr Alan Thorne, was originally assigned an age of 26,000
years. Later, by using a different dating method, Bowler lifted the age to 40,000–45,000
years. More dating tests by Thorne raised the age even highter, to 62,000 years.
But this contradicts Bowler’s preferred ‘Out of Africa’ model,
so he will only accept results in the vicinity of 40,000 years. (See
The dating game.) This is far from the only example of discordant dates
arising from different tests being conducted by different individuals—see
Titanic terror bird.
Another classic case is the evolutionary dating of ‘Mitochondrial Eve’—see
A shrinking date for ‘Eve’.
Based on molecular clock assumptions, researchers placed ‘Eve’ between
70,000 and 800,000 years ago, with most ages falling around the 200,000 year mark.
However, a 1997 study revealed that the observed substitution rate of mtDNA in contemporary
humans was as much as 20 times higher than previously estimated. This would mean
that mitochondrial Eve ‘lived about 6,500 years ago—a figure clearly
incompatible with current theories on human origins ...’ But it is compatible
with the biblical creation account. It is crucial to remember that all dating methods
are based on assumptions about past conditions. Without an actual eyewitness account,
these ‘dates’ can be off by many orders of magnitude—e.g. the
‘popular’ date can often quickly become ‘out-of-date’ when
assumptions are changed and methods are altered.
Creationists, on the other hand, look to the infallible eyewitness account
of Genesis to establish a scientific and historical framework for dating past events.
Therefore, the latest Chinese human fossil is not 38,500–42,000 years old,
nor is Mungo Man 40,000–62,000 years old. These ancient, fully human fossils
should be more accurately dated to less than 4,500 years ago, after the global Flood
and the dispersion of people groups at Babel.
Related products
References
- China’s earliest modern human, Physorg http://www.physorg.com/news94753229.html,
02 April 2007. Return to Text.
- Shipman, P., On the origin of races, New Scientist
137(1856):34, 1993. Return to Text.
- Prior e-mail discussion with Dr Rob Carter (genetics). Return to Text.
- Owen, J., DNA varies more widely from person to person, genetic
maps reveal, http://news.nationalgeographic.com/news/2006/11/061122-human-genetics.html,
22 November 2006. Return to Text.
- Moulson, G., Neanderthal genome project launches, AP, 20 July 2006.
Return to Text.
|
