Lake Mungo remains

Mungo Man

The Lake Mungo remains are three prominent sets of bodies: Lake Mungo 1 (also called Mungo Lady, LM1, and ANU-618), Lake Mungo 3 (also called Mungo Man, Lake Mungo III, and LM3), and Lake Mungo 2 (LM2). Lake Mungo is in New South Wales, Australia, specifically the World Heritage listed Willandra Lakes Region.

LM1 was discovered in 1969 and is one of the world's oldest known cremations. LM3, discovered in 1974, was an early human inhabitant of the continent, who is believed to have lived between 40,000 and 68,000 years ago, during the Pleistocene epoch. The remains are the oldest anatomically modern human remains found in Australia to date. His exact age is a matter of ongoing dispute.

Geology

The shore of Lake Mungo.

Landsat 7 imagery of Lake Mungo. The white line defining the eastern shore of the lake is the sand dune, or lunette, where most archaeological material has been found

Lake Mungo is a dry lake located in south-eastern Australia, in the south-western portion of New South Wales. It is about 760 kilometres (470 mi) due west of Sydney and 90 kilometres (56 mi) north-east of Mildura. The lake is the central feature of Mungo National Park, and is one of seventeen lakes in the World Heritage listed Willandra Lakes Region. Sediments at Lake Mungo have been deposited over more than 100,000 years. There are three distinct layers of sands and soil forming the Walls. The oldest is the reddish Gol Gol layer, formed between 100,000 and 120,000 years ago. The middle greyish layer is the Mungo layer, deposited between 50,000 and 25,000 years ago. The most recent is the pale brown Zanci layer, which was laid down mostly between 25,000 and 15,000 years ago.

The Mungo layer, which was deposited before the last ice age period, is archaeologically the richest. Although this layer corresponds with a time of low rainfall and cooler weather, more rainwater ran off the western side of the Great Dividing Range during that period, keeping the lake full and teeming with fish and waterbirds. It supported a significant human population and had abundant resources, as well as many varieties of Australian megafauna.

During the last ice age period, the water level in the lake dropped, and it became a salt lake. This made the soil alkaline, which helped to preserve the remains left behind.

Lake Mungo 1 (LM1)

LM1 was discovered in 1969 in the Willandra Lakes Region by Jim Bowler with the University of Melbourne. LM1 has been 14C dated at 24,700 to 19,030 years ago. A date of 26,250 ±1120 BP was achieved with charcoal from a hearth 15 cm above the burial. Preservation of the remains is poor. Very limited detailed information was published before the bones were unconditionally repatriated to the Indigenous people of Australia in 1992. A lack of a detailed description of the remains along with a limited distribution of casts with no access to the original artifacts makes it difficult to assess the published material.

Cremation burial

The reconstruction and description were mainly done by Alan Thorne at the Australian National University. The LM1 was an early human inhabitant of the continent of Australia. Her remains are one of the oldest anatomically modern human remains found in Australia.

It represents one of the world's oldest known cremations. The finding implies that complicated burial rituals existed in early human societies.

The pattern of burn marks on the bones of LM1 is thought to imply that after she died, the corpse was burned, then smashed, then burned a second time before being liberally covered with ochre sourced from a location several hundred kilometres from the site. One suggested explanation for this behaviour is that the process was perhaps a ritual wherein the descendants try to ensure that the dead did not return to haunt them.

Current status

The bones were unconditionally repatriated in 1992 to the traditional owners, an alliance called the Three Traditional Tribal Groups (3TTG), consisting of the Paakantji, the Mathi Mathi, and the Ngiyampaa. LM1 had become a symbol of the long Aboriginal occupation in Australia, and an important icon for both archaeologists and indigenous Australians. LM1 is now in a locked vault at the Mungo National Park exhibition centre. The vault has a double lock and can only be opened if two keys are used. One key is controlled by archaeologists, the other by the local indigenous peoples.

Lake Mungo 3 (LM3)

Discovery

Lake Mungo 3 (LM3) was discovered by ANU geomorphologist Dr. Jim Bowler on 26 February 1974 when shifting sand dunes exposed his remains. He was found near Lake Mungo, one of several dry lakes in the southeast part of the continent and 500m east of the LM1 site. The body was sprinkled with red ochre, in the earliest known example of such a sophisticated and artistic burial practice. This aspect of the discovery has been particularly significant to indigenous Australians, since it indicates that certain cultural traditions have existed on the Australian continent for much longer than previously thought. At the time of LM3's discovery, it was believed that Aboriginals had arrived in Australia from Asia around 20,000 years ago. Further archeological finds at Lake Mungo suggests that human occupation of the area dates as far back as 50,000 years ago.

Morphology

The skeleton had belonged to an individual who, based on evidence of osteoarthritis in the lumbar vertebrae, eburnation, and severe wear on the teeth with pulp exposure, was about 50 years old – relatively old for an early human – when he died. The bone structure had a gracile character, which contrasts with the morphology of modern indigenous Australians. Parts of the skeleton had deteriorated in situ: substantial portions of the skull were missing and most of the bones in the limbs have suffered surface damage.

Determination of LM3's sex was initially difficult, due to the deterioration of the skull and pelvis bones, which normally carry many features used for this purpose. Nevertheless, studies of other features suggest strongly that the remains were those of an adult male. Subsequent studies using the length of limb bones to estimate LM3's height, suggest a height of 196 centimetres (77 inches or 6 ft 5 in), a height that is unusually tall for modern Aboriginal males.

LM3 had been buried lying on his back, with hands interlocked over his groin.

Age

The first estimate of LM3's age was made in 1976, when the team of paleoanthropologists from the Australian National University (ANU) who excavated LM3 published their findings. They estimated that LM3 was between 28,000 and 32,000 years old. They did not test LM3's remains directly, but rather established an estimate by stratigraphic comparison with LM1, an earlier set of partially cremated remains also found at Lake Mungo.

In 1987, an electron spin resonance test was conducted on bone fragments from LM3's skeleton, which established an estimate of his age at 31,000 years, plus or minus 7,000 years. In 1999 Thermoluminescence dating work was carried out on quartz from unburnt sediment associated with the LM3 burial site with the selective bleach results indicating a burial older than 24,600 ± 2,400 and younger than 43,300 ± 3,800 years ago. Later Thorne et al. (1999), arrived at a new estimate of 62,000 ± 6,000 years. This estimate was determined by combining data from uranium-thorium dating, electron spin resonance dating and optically stimulated luminescence (OSL) dating of the remains and the immediately surrounding soil.

However, this estimate was very controversial. The lowest level of the LM3 which are as old as 43,000 years demonstrated that LM3 should not be older than the lowest layer. However, the ANU team had dated the stratum itself to be between 59,000 and 63,000 years old. The problems with using uranium-thorium dating on tooth enamel was criticized. The results from 25 additional OSL tests suggests that LM3 can not be older than 50,000 years BP. According to anthropologist Peter Brown, with the absence of the original deposit that once lay above the burial, a minimum age for the burial has not been established, only a possible maximum.

In 2003, collaboration of several Australian groups reached a consensus that LM3 is about 40,000 years old. This age largely corresponds with stratigraphic evidence using 4 different dating methods. The age of 40,000 years is currently the most widely accepted age for the LM3, making LM3 the second oldest modern human fossil east of India. The study also found that LM1 was a similar age to LM3, and not 30,000 years old, as previously thought. The LM1 remains are generally held to be the earliest evidence of human cremation yet discovered.

The current mainstream thinking, the recent African origin of modern humans model, suggest that all humans alive today descended from a small group, which left Africa at a specific time, currently generally estimated at about 60,000 years ago. This estimate of 60,000 years is arrived at from the recent breakthrough of widespread genetic investigation. In the model, humans then fairly quickly spread over the whole globe, from that starting point or bottleneck (indeed, with Australia being perhaps the furthest, most difficult to reach, area).

This explains the controversy of Thorne and other's older dates for LM3 - the establishment of (fully modern) human settlements in the different continents, could only have happened after (although perhaps remarkably shortly after) the exodus of the original (perhaps remarkably small) group of humans who left Africa via the middle-East.

Mitochondrial DNA and origins

In 2001, mitochondrial DNA (mtDNA) from the Lake Mungo 3 (LM3) skeleton was published and compared with several other sequences. It was found to have more than the expected number of sequence differences when compared to modern human DNA (CRS). A portion of the mtDNA of LM3 survives in modern humans as a segment found in chromosome 11.

The divergence of the LM3 sequence before the MRCA of contemporary human sequences is indicated by its grouping with the Insert sequence (Fig. 1B), which other reports have suggested diverged before the MRCA of sequences in living humans

Comparison of the mitochondrial DNA with that of ancient and modern Aborigines has indicated that Mungo Man is not related to Australian Aborigines. The results indicated that Mungo Man was an extinct subspecies that diverged before the most recent common ancestor of contemporary humans. These results, if correct, may support the multiregional origin of modern humans hypothesis.

These claims are both scientifically and politically controversial and have been met with a general lack of acceptance in scientific communities, the sequence is criticized as there has been no independent testing and some of these differences may be due to posthumous modification and thermal degradation of the DNA. Authentication tests need to be performed before the results can be accepted but further testing is unlikely as the indigenous custodians, the Paakantji, the Mathi Mathi, and the Ngiyampaa, are not expected to allow further invasive investigations.

Further discoveries

In 1988, the skeleton of a child believed to be contemporary with Mungo man was discovered. Investigation of the remains was blocked by the 3TTG with the remains subsequently protected but remaining in-situ. An adult skeleton was exposed by erosion in 2005 but by late 2006 had been completely destroyed by wind and rain. This loss resulted in the indigenous custodians receiving a government grant of $735,000 to survey and improve the conservation of skeletons, hearths and middens that were eroding from the dunes. Conservation is in-situ and no research is permitted.

Tourism

Mungo National Park can be visited by tourists and is accessed by an unsealed road. Boardwalks have been installed throughout the sand dunes and visitors are forbidden from stepping off the boardwalks unless accompanied by an Aboriginal guide. In 2014, fake bones were buried throughout the area as part of an experiment for La Trobe University. Within two weeks, nearly all of the artificial bones had disappeared.

See also

• Recent African origin of modern humans
• Multiregional origin of modern humans

Further reading

• Anne-Marie, Cantwell, "Who Knows the Power of His Bones": Reburial Redux, Annals of the New York Academy of Sciences (2000).
• General Anthropology Bulletin of the General Anthropology Division Vol. 10, No. 1, pp. 1–15, (2003)