The dating game
by Tas Walker
In western New South Wales, Australia, part of a semi-arid desert has been set aside
as a World Heritage area.1 This may
seem curious for such an inhospitable region. But there is a good reason. Evolutionists
believe that the site represents an outstanding example of the major stages in man’s
evolutionary history.
Photo by Carol Drew
Lake Mungo
It all centres on the discovery of human remains in sand dunes surrounding ancient
Lake Mungo—now a dry, flat plain, vegetated by scraggly salt-tolerant bushes
and grasses.
The first major find, in 1969, was of crushed and burnt skeletal fragments, interpreted
to be of a female called Lake Mungo 1, or more affectionately Mungo Woman.2,3 What made the find
significant was the assigned date. Carbon-14 dating (see Dating methods)
on bone apatite (the hard bone material) yielded an age of 19,000 years and on collagen
(soft tissue) gave 24,700 years.3 This excited the archaeologists, because
that date made their find the oldest human burial in Australia.
But carbon-14 dating on nearby charcoal produced an ‘age’ up to 26,500
years. This meant that the skeleton, buried slightly lower than the charcoal, must
have been older. Not surprisingly, the older charcoal age was considered to be the
‘most reliable’ estimate3 and launched Mungo Woman to national
and international fame. Jane Balme, of the Centre for Archaeology at the University
of Western Australia, put it succinctly, ‘There’s a general perception
that there is a competition to get the oldest date and there’s kudos in it.’4
Evolution and the first Australians1
Darwin considered the Australian Aborigines as primitive and not much evolved from
the ‘anthropoid apes’. He anticipated that the ‘wilder races’
would become extinct because survival of the fittest meant they would be superseded
by the evolutionarily-advanced ‘civilised’ races.2 An evolutionary
view of human origins underlies the World Heritage listing of the Lake Mungo site.
Such a view was not good for the first Australians. Many atrocities were perpetrated
on Aboriginal communities because of these evolutionary beliefs.
Incredibly, in the 1800s, it was not uncommon for Aboriginal people to be hunted
and shot as specimens for science.3 Their remains were sent to Europe
to illustrate evolution displays in museums. Only now are these remains being returned
to their communities.4
But the Bible records our true human history. The first Aboriginal settlers to Australia
were descended from people as intelligent and inventive as any other culture at
that time. Like everyone else, they were descended from Noah, who built and managed
the Ark, and from a people who developed an advanced civilization around the Tower
of Babel.5
The Aborigines of Australia lost some of their technological know-how—it can
happen in a generation if parents do not pass it on to their children. (Perhaps
it was because of isolation and the pressure to cope with a worsening climate as
the continent dried out after the Ice Age.) They, like other peoples, are made ‘in
the image of God’ (Genesis
1:26).
References and notes
- For more information, see
We all belong to one human race, the only answer to racism, 14 August 2003.
- Darwin, C., The Descent of Man and Selection in Relation to Sex, 2nd
ed., John Murray, London, p. 188, 1887.
- Wieland, C., Darwin’s
bodysnatchers: new horrors, Creation 14(2):16–18,
1992.
- Aboriginal remains returned to Coorong tribe, ABC Canberra News, www.abc.net.au/canberra/news/metact-5may2003-2.htm,
5 May 2003.
- For more information, see: McKeever, S. and Sarfati, J.,
Was Adam from Australia? The mystery of Mungo Man, 17
January 2001, updated 20 February 2003.
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Certainly, there was kudos in this date. At 26,000 years, Mungo Woman was nearly
twice as old as the previous oldest date for Aboriginal settlement of Australia,
and possibly the earliest human cremation in the world.
Then, in 1974, Bowler and Thorne found a skeleton sprinkled with powdered red ochre
in a grave only 450 metres away.5
This one was well preserved and similar to the skeletons of modern Aborigines. Because
the new skeleton, Lake Mungo 3, was found in the same sand bed (technically the
same stratigraphic horizon), ‘he’ was assigned the same age as Mungo
Woman. Thus Mungo Man became famous too—one of the world’s earliest
ritual burials (even though the sex of the individual is still in dispute6).
The situation became even more exciting when a different dating method (thermoluminescence,
see Dating methods) was used. In 1998, Bowler reported that
sand from the Mungo 3 site gave an age of some 42,000 years.5,7 Being older than the carbon-14 dates, Mungo Man acquired
a new stature on the world evolution scene. So, the earlier ‘reliable’
carbon-14 ages were abandoned in favour of the thermoluminescence ones.
Then, in 1999, Thorne (not to be outdone) and other scientists from the Australian
National University published a new comprehensive study on the age of Mungo Man.
They used different samples of bone and sand and different dating methods—electron-spin
resonance (ESR), optically-stimulated luminescence (OSL), thorium-uranium (Th/U)
and protactinium-uranium (Pa/U). (Don’t worry about the big names. See
Dating methods.) And the results from all the different methods agreed closely.
Their conclusion? Mungo Man was 62,000 years old! Bowler and Magee described this
20,000-year stretch as ‘commendable in intent.’8
There was just one small problem. The new date meant that the history of Australian
occupation would have to be rewritten and it also affected the ideas of human evolution
in other parts of the world. And Australian archaeologists were still embarrassed
by the Jinmium rock shelter fiasco, where a claimed age of 116,000 years was later
reduced to 5,000 years.9
So, Bowler stubbornly refused to accept the new dates. In his protest to Journal
of Human Evolution, he said ‘For this complex, laboratory-based dating
to be successful, the data must be compatible with the external field evidence.’8
In other words, you don’t just accept a laboratory date without question.
It’s not the last word on the age of something. You only accept the date if
it agrees with what you already think it should be.
And that is what we have been saying all along.10
That is why we won’t accept any date that contradicts the eyewitness evidence
of human history recorded in the Bible. Such contradictory dates can’t be
right.
In short, the dates are wrong because they are based on wrong assumptions.
For example, the carbon-14 method does not account for the disruption of the carbon
balance during the Flood some 4,500 years ago.11
The uranium methods do not make the correct assumptions about the initial conditions
of the samples or about the effects of changing environmental conditions through
time. The luminescence dates have the same problem.
So, who are Mungo Man and Mungo Woman? Like us, they descended from Noah and his
family (Genesis
10). After the Flood, and after the confusion of languages at the Tower
of Babel (Genesis
11), their ancestors migrated to Australia. As the populations grew, they
spread out over the continent. During the Ice Age, when rainfall was higher, Lake
Mungo would have been a lush area to live in, teeming with wildlife.
Dating methods1
- Carbon-14 dates are determined from the measured ratio of radioactive carbon-14
to normal carbon-12 (14C/12C). Used on samples which were
once alive, such as wood or bone, the measured 14C/12C ratio
is compared with the ratio in living things today. The date is calculated by assuming
the change of 14C in the sample is due entirely to radioactive decay.
It is also assumed that carbon has been in equilibrium on the earth for hundreds
of thousands of years.
Wrong dates are usually caused by assuming a wrong initial 14C/12C
ratio, contamination or leaching. Samples from before the Flood, or from the early
post-Flood period, give ages that are too old by tens of thousands of years. This
is because the Flood buried lots of 12C-rich plants and animals. This
would result in a lower 14C/12C ratio, which is wrongly interpreted
as great age.
- Thermoluminescence (TL) dates are obtained from individual grains of common minerals
such as quartz. When such grains are heated, they emit light, and this is related
to the radiation ‘stored’ in the crystal structure. It is assumed that
the radiation was slowly absorbed from the environment, building up from zero at
a certain time in the past (perhaps when the grain was last exposed to sunlight).
A date is calculated by measuring the light emitted from the mineral grain when
it is heated, and measuring the radiation in the environment where the grain was
found.
Unfortunately, there are many unknowns and many assumptions need to be made, including
the amount of radiation ‘stored’ in the mineral at a certain time in
the past, that the change in radiation has only been affected by the radiation in
the environment, that the radiation in the environment has remained constant, and
that the sensitivity of the crystal to radiation has not changed. All these factors
can be affected by water, heat, sunlight, the accumulation or leaching of minerals
in the environment, and many other causes. - Optically-stimulated luminescence
(OSL) dates are based on exactly the same principle as TL. But instead of heating
the grain, it is exposed to light to make it emit its ‘stored’ radiation.
The calculated date is based on the same assumptions, and affected by the same uncertainties,
as for TL.
- Electron-spin resonance (ESR) dates are based on the same principles as TL and OSL.
However, the ‘stored’ radiation in the sample is measured by exposing
it to gamma radiation and measuring the radiation emitted. The measuring technique
does not destroy the ‘stored’ radiation (as does TL and OSL), so the
measurement can be repeated on the same sample. The calculated date is based on
the same assumptions, and affected by the same uncertainties, as for TL and OSL.
- Thorium-uranium (Th/U) dates are based on measuring the isotopes of uranium and
thorium in a sample. It is known that uranium-238 decays radioactively to form thorium-230
(through a number of steps, including through uranium-234). The dating calculation
assumes that the thorium and uranium in the sample are related to each other by
radioactive decay. Furthermore, before a date can be calculated, the initial ratios
of 230Th/238U and 234U/238U need to
be assumed, and it is also assumed that there has been no gain or loss of uranium
or thorium to/from the environment—i.e., that the system is ‘closed’.
However, the bone and soil must have been ‘open’ to allow these elements
to enter and accumulate.
- Protactinium-uranium (Pa/U) dates are based on similar principles as Th/U dating,
but use uranium-235 and protactinium-231 instead. The isotope 235U decays
radioactively to form 231Pa. Again, it is assumed that the isotopes in
the sample are related to each other by radioactive decay. Also, the initial ratio
of 231Pa/235U has to be assumed, and it is assumed that there
has been no gain or loss of uranium or protactinium to/from the environment—i.e.,
that the system is ‘closed’. Again, any bone sample containing uranium
must have been ‘open’ to allow it to accumulate in the first place.
Reference
- Details about dating methods may be obtained from such sources
as:
Smart, P.L. and Frances, P.D. (Eds.), Quaternary Dating Methods—A User’s
Guide, Quaternary Research Association, Technical Guide No. 4, Cambridge,
1991, or
Faure, G., Principles of Isotope Geology, 2nd edition, John
Wiley & Sons, New York, USA, 1986.
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References
- Willandra Lakes Region: inscribed 1981, <www.ea.gov.au/heritage/awhworldheritage/sites/willandra/>,
4 August 2003. Return to text.
- Fannin, P., Mungo jumbo, The Age, p. 5, Saturday, 13 January
2001. Return to text.
- Brown, P., Lake Mungo 1, <www-personal.une.edu.au/~pbrown3/Mungo1.html>,
21 February 2003. Return to text.
- In the beginning, The Bulletin, pp. 26–33, 24 June
2003. Return to text.
- Thorne, A., et al., Australia’s oldest human remains:
age of the Lake Mungo 3 skeleton, Journal of Human Evolution 36:591–612,
1999. Return to text.
- Brown, P., Australian Pleistocene variation and the sex of Lake
Mungo 3, Journal of Human Evolution 38:743–749,
1999. Return to text.
- Bowler, J.M., et al., New ages for human occupation and
climatic change at Lake Mungo, Australia, Nature 42(6925):837–840,
2003. Return to text.
- Bowler, J.M. and Magee, J.W., Redating Australia’s oldest
human remains: a sceptic’s view, Journal of Human Evolution 38:719–726,
2000. Return to text.
- Brown, P., The first Australians: the debate continues, Australasian
Science 21(4):28–31, 2000. Return to text.
- Walker, T.,
The way it really is: little known facts about radiometric dating, Creation
24(4):20–23, 2002. Return to text.
- Batten, D. (Ed.), The Creation Answers
Book, Creation Ministries International, Brisbane, Australia, Chapter
4, 2006. Return to text.
(Available in Polish)
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