Maxime Aubert

Maxime Aubert

I am Maxime Aubert, a Professor in ARCHE at Griffith University. I specialise in the development and application of analytical techniques to key questions in human evolution and rock art.

Location I live in Northern New South Wales, Australia

Activity

  • @JScottLooman The two dates in question are minimum - it doesn't mean they were made 5000 years apart.

  • We have dates from multiple popcorn in the same cave - even over the same image. Contamination is usually from dust but its is easily identified and can be corrected for if its negligible.

  • Hi Amelia, We can sometimes correct for impure samples but we cannot correct for open system. We can only test for open or close system.

  • Yes leaching of uranium could be a problem. If so, the ages will be too old. Thats why we always sample a series of layers. They should get younger towards the surface of the sample. If we have a reverse age profile it means that uranium has leached out. It wasn't a problem for any of our samples

  • Hi John, Thank you for your question. Uranium is soluble in water but thorium is not. We can see large stalactites and stalagmites in the caves but I suspect they are much older. The popcorn are found on the ceiling and top walls. They can also form from condensation. I believe the monsoon started to intensified about 15,000 years ago - after the LGM.

  • Most of the ancient cave surfaces are gone but where remnants of the old surfaces are still there we often see paintings - even deep inside caves where most of the old cave surfaces have disappeared.

  • The pigment is made of iron oxide hematite. We haven't found the source.

  • Hi Alvaro, Yes the Deep Skull from Borneo is about 40,000 years old.

  • Hi Erin, Thank you for your question. 28,000 years is generally accepted as the oldest dated rock art in Australia. Is is from Narwal Gabarnmang in Arnhem Land.

  • @TrevorHawkeswood Unfortunatly they're not but just send me an email m.aubert@griffith.edu.eu

  • @JohannaTruijens Its an interesting hypothesis but unfortunatly not something we can prove or disprove.

  • @AndrewHainsworth No, the limit of the technique is about 600 000 years. Its because we don't have any evidence for modern humans in Southeast Asia dating to 100 000 +.

  • @EugeniaFaces If the U-series dates the layer above the painting it provides a minimum age and If it dates the layer under the painting it provides a maximum age for that painting. If the charcoal pigment layer is directly dated with radiocarbon it only provides the age of the charcoal (essentially when the tree died) hence the maximum age. It doesn't date...

  • Hi Janet. We need to do more research in order to understand whats going on but I suspect that local limestone mining has an impact.

  • Hi Ali, Its a good question. The short answer is no. To date the calcite we need a mass spectrometer with a huge magnet. We also need to do wet chemistry before we can run the samples on the mass spectrometer. I have experimented with laser a ablation system so we don't need to do wet chemistry but we still need the giant mass spectrometer and the laser...

  • Hi Michael, Yes, the oldest rock art from Africa is from Apollo 11 Cave in Namibia. There are much older traces of possible ocher use (for example at Blombos cave in South Africa) with incised ochre pieces, ochre in shell vessel interpreted as a painting kit, ochre supposedly dawned on a rock surface. In my views, these are all circumstantial evidences. It is...

  • Hi Alan, We also get maximum ages for the art from calcite layers underneath the pigment layer. Sometimes the maximum age is older than 100,000 years so not meaningful. On other occasions we were able to bracket the age of the pigment layer between 42,000 and 28,000 years; 35,000 and 28,000 years; 27,000 and 23,000 years. The youngest maximum age we have for...

  • @ColinArmstrong we don't know

  • Hi Antje. Thank you for your question. I personally don't have any issues with the possibility that Neanderthals were engaging in cave art but I have issues on how the samples were taken in that study. I believe that the samples could be maximum rather than minimum ages. My colleague and I wrote a reply:...

  • Hi Margaret. Thank you for your comment. We recently did a short film with the English sculptor Antony Gormley. It was interesting to hear an artists point of view. The film was broadcasted 2 weeks ago on the BBC in the UK. It is called 'How Art Began'.

  • Hi Rebecca, The sampling of mineral deposits in association with rock art will always be destructive. We are only taking a very small sample after obtaining permission for each individual samples from the Indonesian Department of Conservation and Heritage. From our perspective, our carefully considered sampling of some of the pigment concealed beneath...

  • Hi Colin, For Leang Lompoa 1, we found traces of pigment where the middle finger should have been. To me, this suggest that the 'baby' and 'ring' fingers were folded against the cave wall leaving a void under the middle finger for pigment to be blown in.

  • Hi Karen, Thank you for your comments. Yes we have dated the mineral layer under the pigment providing maximum ages for the art. Sometimes the maximum age is older than 100,000 years so not meaningful. On other occasions we were able to bracket the age of the pigment layer between 42,000 and 28,000 years; 35,000 and 28,000 years; 27,000 and 23,000 years. The...

  • Hi Valentina, It is sometimes possible to date the pigment if it contains organic matter (using radiocarbon) but this is quite rare and the method can be problematic. You can read about it at:https://www.journals.uchicago.edu/doi/10.1086/694414

  • Hi Bill,
    The El Castillo date was 40,800 years old so essentially at the same time that modern humans arrived in Europe. Since in was a minimum age (the dated sample was on top of the painting) the authors of the study proposed that it could be Neanderthal.
    In a more recent study the same team manage to get much older dates for "Neanderthal cave art". See:...

  • Hi Samuel, The cave popcorns are actually quite rare and I think they help preserving the art (even if sometimes its hard to see the art). Perhaps one day we will have the technology to image the art through the popcorn.

  • Hi Catriona, You're right, climatic condition play a role in the formation of cave popcorn. In this case we know that they have been forming for tens of thousands of years.

  • Hi Ruth, the cave popcorn doesn't form in the shape of the art. We have to visit a lot of caves before we can find images that are in clear association with a popcorn sample. Human saliva would have no impact on popcorn formation.

  • Hi Chris,
    There are no 40,000 years old dates for rock art in Australia. This is based on assumptions by some archaeologists and is not supported by scientific data.

  • Hi Amanda, the paper you refer to can be found at: http://www.pnas.org/content/early/2017/03/28/1619013114

    It is not just rock art in Sulawesi but also what appears to be portable ornements and also multiple ochre pieces found in stratified archaeological deposits. The deposits are contemporaneous to the rock art.

    We don't know exactly how they made the...

  • Hi Barbara, When possible we also try to get calcium carbonate from under the art in order to provide maximum age. This is the only was we can see continuity or changes in the art through time.

  • Hi Alyson, Sulawesi in on the eastern side of the Wallace line so it was never connected to mainland Asia. There are similar paintings in Borneo, on the western side on the Wallace line. We have a paper coming out shortly on the dating of cave art from Borneo.

  • Hi Amanda and Marie, These are all interesting questions. There are are so many examples of hand stencils in this region of Sulawesi. We will probably never know what they meant to people 40,000 years ago but there are sections of caves that are exclusively covered with children hand stencils.

  • Hi Jayne and Janet, I have my doubts about the early date for "Neanderthal cave art". The association between the dated samples and the art is not clear and I suspect that the old ages are in fact maximum ages rather than minimum ages for the art. See our latest paper at: https://www.sciencedirect.com/science/article/pii/S0047248418300915

  • Hi Rachael,

    At the time we had no idea about the age of the rock art.
    But the Indonesian government was very supportive and were/are an integral part of our research team.

  • Hi Cathy,

    Cave art provides an invaluable and irreplaceable record of
    ancient human visual culture, and it is never a simple matter or an
    easy choice from an ethical perspective to justify its partial
    destruction for scientific research. However, archeology, by nature,
    often involves the destruction of the primary evidence, including
    the exhumation of...