Stone Age drawings showed Lunar calendar?

[Brian G Turner]

This is fascinating, and will be interesting to see what follow-up studies show on this:

Londoner solves 20,000-year Ice Age drawings mystery

Furniture conservator Ben Bacon spent hours of his own time decoding markings on cave paintings.

www.bbc.co.uk

 

[SilentRoamer]

It makes perfect sense, we were migratory and birth cycles would have been a huge part of our migratory movements. Very interesting stuff and well done to Mr. Bacon.

 

[Matteo]

Thanks @Brian G Turner. Would love to read the paper - need to search for that later. Initially I'm skeptical (mainly because I fear that if you want something to have some meaning you can find a way to make it fit).

But, like I said, need to read the paper.

 

[Matteo]

[insert that emoticon where the "smiley" is banging his head against a wall] It's here:

An Upper Palaeolithic Proto-writing System and Phenological Calendar | Cambridge Archaeological Journal | Cambridge Core

An Upper Palaeolithic Proto-writing System and Phenological Calendar

www.cambridge.org

 

[Matteo]

Finally got around to reading this, after printing it off a month ago.

I'm not convinced.

I will certainly accept that the dots and lines represent a numerical notation of some sort - it makes little sense otherwise. But find the authors' conclusions that they are linked to lunar months (specifically mating and birth months) as a method of recording time, a stretch.

They, more or less, dismiss the notion that the dots/lines represent actual numbers: It seems to us unnecessary to need to convey information about the numbers of individual animals, the times they have been sighted, or the number of successful kills of these;

I would suggest that the dots/lines could indeed represent the number of kills. It could simply be an indication of prowess, i.e., "hey! we killed this many!". Or more seriously, "we needed to kill this money to feed the tribe", or perhaps "it needed this many humters to kill this animal". It could also represent a rating "this animal tastes this good".

The authors, in the same sentence, link it to numbers of individuals "it seems far more likely that information pertinent to predicting their migratory movements and periods of aggregation, i.e. mating and birthing when they are predicably located in some number and relatively vulnerable, would be of greatest importance for survival." but I question the leap I have emboldened; my suggestions above could still fit with periods of migration, mating, birthing.

One illustration, taken from Lascaux, shows a red deer with seven dots (part of a larger fresco with more deer).

The authors note that among its row of ‘swimming’ deer stags—usually interpreted as an autumn migration scene—one stag is marked with seven red dots; and this they later link to mating season. But why should this show a migration? It could simply be a herd stampeeding. And at any time of the year.

If one does accept their hypothesis regarding the dots/dashes as indicating months, then there does seem to be a correlation regarding the "Y" mark (birth) and they make the assumption that the "Y" represents parted legs which is reasonable, but not conclusive. In addition, I did not see any evidence that they could link this to depictions of animals wth an obvious gender. And it's interesting to note that the same mark is "one of the most commonly depicted in Palaeolithic art" so it could mean many things.

I have to admit that the statistical analysis that they detail in the paper is beyond me so I cannot speak to its validity. However, and that said, I'm not convinced.

Very interesting though!

 

[Swank]

I don't see why it pays to be critical of a theory based on statistical analysis if you haven't looked into those statistics. That was the sole basis of the interpretation.

When I heard this story on public radio, I was at first surprised that no one had ever considered lunar cycles. To people without other means of documenting the passage of time other than seasons and days, the wax and wane of the moon must have been like the ticking of an enormous clock.

 

[Matteo]

I did look at the statistics - as displayed in the paper - and to me, it seems that they tried to use them to fit their hypothosis. An hypothosis that I felt was rather subjective - the markings could represent something else.

What I meant by it "being beyond me" was that I have no knowledge of, for example, the procedure ‘glm’ with a logit binomial family link function. Or the ANOVA procedure with a chi-squared model comparison test, Or the R package ‘DHARMa’ (Hartig 2022) to test deviation, dispersion and occurrence of outliers prior to logistic regression.

If you are more versed in this than I, and can rely on it being valid to prove the hypothosis, then I can see why you would have a different opinion.

 

[Swank]

I did look at the statistics - as displayed in the paper - and to me, it seems that they tried to use them to fit their hypothosis. An hypothosis that I felt was rather subjective - the markings could represent something else.

What I meant by it "being beyond me" was that I have no knowledge of, for example, the procedure ‘glm’ with a logit binomial family link function. Or the ANOVA procedure with a chi-squared model comparison test, Or the R package ‘DHARMa’ (Hartig 2022) to test deviation, dispersion and occurrence of outliers prior to logistic regression.

If you are more versed in this than I, and can rely on it being valid to prove the hypothosis, then I can see why you would have a different opinion.

No, I just meant that everything I heard about the analysis from the amateur that did it was that he treated the data as a code to break without having a particular pre-conception. That's where those functions neither of us is familiar with come in.

He certainly could be lying. I just don't like starting with that premise.

 

[Matteo]

I'm sure that the amateur and the authors behind the paper are not lying.

However, my concern with that is there appears to have been an initial "manipulation" to make the data fit. They state "these artificial/external memory systems would have limited use unless their sequence of months could be anchored to a well-defined start date, in other words, a calendar." This reasonable, and is certainly needed to fit their hypothosis. However, they go to say "Many annual calendars are based on astronomy: for example, the timing of the equinoxes and solstices. However, these are hard to observe and, while pertinent to the agricultural year, are not relevant for Palaeolithic hunter-gatherers." It is here that I start to doubt their methods. Surely the winter/spring equinox is an ideal "start" to the year (and are they difficult to observe?) - regardless of whether you are agrarian or hunter gatherers. Unfortuantely, that would put their start date back two months (March) and the data would no longer fit. They instead use "bonne saison" as the start point - as spring, starting in late May.

I also wonder why it would be neccessary to point out mating and birth seasons. Surely this would be observed (and therefore known) by descendants of the cave painters? Arguably, the same could be true for my suggestions (number of kills needed to feed the tribe, or number of hunters needed) but I would argue that this would be more useful to know in advance. Of course, it could simply be "this many killed".

The above said, it's still a fascinting paper and I'm not prepared to dismiss it entirely.

 

[Wayne Mack]

Surely the winter/spring equinox is an ideal "start" to the year (and are they difficult to observe?)

The winter and summer solstices are the shortest and longest days of the year, while the spring and fall equinoxes are the days when daylight and darkness are equal. Without a pretty precise way to measure these, it would seem doubtful that one could simply observe them. In non-tropical locations, hunters would be aware of springtime events, such as animals emerging from hibernation and the birth of young. Likewise, gatherers would be aware of new plant growth and later flowering that presages fruit.

 

[Wayne Mack]

a chi-squared model comparison test

This is the key part of the argument (other references appear to be related to a particular software package used for statistical analysis). A chi-squared test is a way of determining the level of correlation between two data sets, in this case, lunar months from an arbitrary spring time to the number of dots. This is summarized in the two statements, "The first key message is that the birth periods are significantly well predicted by the position of <Y> (p < 0.0146)" and "Our second key finding is that mating periods are significantly well predicted by length of sequences of dots or lines not containing a <Y> (p = 0.00236)." This, of course, does not disprove other interpretations, but other meanings would need to show at least as strong a correlation to challenge this one.

 

[Cthulhu.Science]

This is the key part of the argument (other references appear to be related to a particular software package used for statistical analysis). A chi-squared test is a way of determining the level of correlation between two data sets, in this case, lunar months from an arbitrary spring time to the number of dots. This is summarized in the two statements, "The first key message is that the birth periods are significantly well predicted by the position of <Y> (p < 0.0146)" and "Our second key finding is that mating periods are significantly well predicted by length of sequences of dots or lines not containing a <Y> (p = 0.00236)." This, of course, does not disprove other interpretations, but other meanings would need to show at least as strong a correlation to challenge this one.

I love that there are members of this site that understand statistics well enough to
A. know what the authors were talking about
B. have a serious opinion about it.

Keep it going guys. This is way, way, way over my head. But this discussion is great!

 

[Cthulhu.Science]

Counter theory.
People making cave paintings were high as a kite and picked caves that would result in hypoxia - to get higher - when they burned torches in them.
Though the theories are probably not mutually exclusive...

Shameless link

 

[Matteo]

The winter and summer solstices are the shortest and longest days of the year, while the spring and fall equinoxes are the days when daylight and darkness are equal. Without a pretty precise way to measure these, it would seem doubtful that one could simply observe them. In non-tropical locations, hunters would be aware of springtime events, such as animals emerging from hibernation and the birth of young. Likewise, gatherers would be aware of new plant growth and later flowering that presages fruit.

It's a reasonable assumption, but it was my understanding that by this time (21,500 BC for the Lascaux paintings) Palaeolithic people were able to plot the equinoxes. I also thought that certain cave paintings depicted these (though my memory may be at fault here). And it made more sense to me to use the "time of the year when days become longer than nights" as the start of the year.

 

[CupofJoe]

The winter and summer solstices are the shortest and longest days of the year, while the spring and fall equinoxes are the days when daylight and darkness are equal. Without a pretty precise way to measure these, it would seem doubtful that one could simply observe them. In non-tropical locations, hunters would be aware of springtime events, such as animals emerging from hibernation and the birth of young. Likewise, gatherers would be aware of new plant growth and later flowering that presages fruit.

Given time it is more than doable. You just need a few decades [if not longer] to repeat the observation, a lot of curiosity and probably a fortuitous event/alignment to get you thinking.

 

[Swank]

It's a reasonable assumption, but it was my understanding that by this time (21,500 BC for the Lascaux paintings) Palaeolithic people were able to plot the equinoxes. I also thought that certain cave paintings depicted these (though my memory may be at fault here). And it made more sense to me to use the "time of the year when days become longer than nights" as the start of the year.

How do you tell that the day is longer than the night when you've method of keeping time is to observe the movement of the sun?

 

[CupofJoe]

How do you tell that the day is longer than the night when you've method of keeping time is to observe the movement of the sun?

There are the stars, constellations etc. as well, as well as the position of where the sun rises and sets and height of the sun across different days [assuming you are not at the poles or equator]. Given a few repetitions [okay, a lot of repetitions] of marking highs and lows, easts and wests, and I think you should be good within a day or two.

 

[Swank]

There are the stars, constellations etc. as well, as well as the position of where the sun rises and sets and height of the sun across different days [assuming you are not at the poles or equator]. Given a few repetitions [okay, a lot of repetitions] of marking highs and lows, easts and wests, and I think you should be good within a day or two.

Those are astronomical observations of the location of the sun in the sky, not direct measures of the length of the day or night in time.

And those sort of observations would require near daily access to a fixed observation point, which might not be possible if you are a migratory hunter.

 

[Elckerlyc]

Hunter/Gatherers lived by the seasons. They migrated, depending on the season and the seasonal products they were after, and would be more alert to what they saw in nature around them, down on Earth. It's dreamers that have the time to look up at the sky and, perhaps after a long while, may notice certain patterns... if they remained on the same spot long enough. It seems more likely to me that it was only with the first settlements, and thus a year-round fixed observation point, that the movement of the sun throughout the year became more apparent.
It's easy for us to say it's quite apparent when you pay attention to it. But that's because we know.
Without clock it's not doable to measure the length of day, let alone establish what the shortest day was. From mid December to mid January there is very little difference noticeable. That's a full moon period.

 

[Swank]

Hunter/Gatherers lived by the seasons. They migrated, depending on the season and the seasonal products they were after, and would be more alert to what they saw in nature around them, down on Earth. It's dreamers that have the time to look up at the sky and, perhaps after a long while, may notice certain patterns... if they remained on the same spot long enough. It seems more likely to me that it was only with the first settlements, and thus a year-round fixed observation point, that the movement of the sun throughout the year became more apparent.
It's easy for us to say it's quite apparent when you pay attention to it. But that's because we know.
Without clock it's not doable to measure the length of day, let alone establish what the shortest day was. From mid December to mid January there is very little difference noticeable. That's a full moon period.

How can certain times year be a "full moon period"? The lunar year is only 354 days long.