Reflectance Transformation Imaging - Update 2

Finally! The marbles arrived, sphere detection worked and I have created my first RTI....

Some snapshots

Using the HSS Fitter with specular enhancement

And then with the PTM algorithm....

Static Multi Light

Coefficient Unsharp Masking

Image Unsharp Masking

I've uploaded a couple of ptm files to my website http://www.palaeoart.com (beware they are large files) for anyone interested in seeing the end result. Additionally the first eight or so pictures were rendered from PTMs and then cut out in Adobe Photoshop.

I have also reduced the overall processing time by using only PTMfitter in conjunction with a single 'lp' (light profile) file. I am quietly pleased with the dome - it does everything I wanted it to do.

Finally, a photo of the finished dome - with protective covering.

Reflectance Transformation Imaging - Update

Finally working. Some issues tackled in the process, including:

The Canon EOS Utility doesn't work on my Windows 10 platform (it appears that I am not alone in this experience). I eventually resigned myself to finding an alternative piece of software to capture and control images directly from the camera.

I made a bracket that I plan can be modified if I use a different camera. 

I changed the configuration of the LEDs slightly. Originally evenly spaced at 10, 30, 50 and 70 degrees, I've moved the top row down to 65 and the bottom row up to 15 - according to CHI the optimum angles at which to set exposure and aperture settings. The picture below shows the dome after these mods.

I did a trial run and found that sphere detection in the Builder process wouldn't work.... Presumably because the black sphere (a pool ball) was too big relative to the highlights. I will test this assumption when the black marbles I have ordered arrive.

Back soon.

Reflectance Transformation Imaging - Dome construction

Today my Cree LEDs and Arduino-type board arrived in the post, closely followed by the 600mm diameter acrylic dome.

Let the build begin....

600mm acrylic dome with flange, 4mm.

Arduino clone

Cree LEDs. I've gone for 4v through the hole for this initial prototype, sacrificing shorter exposure times since I understand the primary constraining factor will be the speed at which the camera will save pictures in RAW format.

Marking the dome up. This dome will have 48 LEDs, so there are four rows of lights. From the top 8, 12, 16 and 12 in the bottom row.

All 48 holes marked up.

This is the clone wired up to the bread-board with three LEDs to test my programming skills! Wired to the board, the jack end of the remote (now cut in two) successfully focuses and then triggers the shutter whilst each LED is lit in turn. I plan to use the remote switch to a) start the sequence or b) manually advance through the sequence.

LEDs and resistors soldered to boards.

Drilling holes into the dome. A jig is used to obtain the correct angle.

Soldering the ground...

And the live wire

Ta-da! Camera hole cut and first coat of black.

Wired up, painted and the clone is in a case... Next step is to test (and debug I expect).

Neanderthal Art II

Now closed. An exhibition of figure-stones and Mousterian tools from the Palaeolithic site of Fontmaure in France.

Watford Museum,

194 High Street,

Watford

Hertfordshire

WD17 2DT

Opening times: Thursday-Saturday 10:00-17:00

Free Admission

Modern humans and refuted hypotheses

This week Chris Stringer tweeted his response to the Nature paper "An early modern human from Romania with a recent Neanderthal ancestor".

Chris Stringer's comments come as no surprise to those closely following his shift in position: from proposing that so-called "anatomically modern humans" originated as a separate species from Africa who upon migrating into Europe were unable to interbreed with the resident Neanderthals which they soon "replaced", to a position which fundamentally refutes this theory.

Stringer may be one of the last anthropologists to be surprised by the results. By referring to the "belief" of a Neanderthal extinction he implies that the results are extraordinary, or in other words not to be expected to be representative of a wider pattern. Of course by applying taphonomic logic it is evident that the results add further to the evidence refuting the idea that Neanderthals became "extinct".

But before examining his comments closer it is important to scrutinise the facts as they are presented. It is implicitly claimed in the title of the Nature paper that Oase 1 is a "modern human" yet even the description of the mandible by Trinkhaus et al cited (http://m.pnas.org/content/100/20/11231) makes it clear that whilst there are some modern features there are also archaic and derived Neanderthal features. At best, the individual could be considered to be transitional (from robust to gracile) but by no stretch of the imagination could it be concluded that they were a "modern human". Indeed if we assume that Oase 1 was indeed a Neanderthal then the results only add to the evidence for continuity between the robust populations of the past and the gracile populations of the present.

Not unusually but rather typically, Neanderthals are presented by the professor as being cognitively inferior to "modern humans" although no evidence is presented to support this claim. Moreover, there is no explanation for why these hypothetical Neanderthals, who if they are assumed to lack "complex technology" or "more complex behaviour", should want to mimic behaviour or adopt technologies that they had no need for. Not only is there no evidence which places a "complex technology" directly with a specific species or even group of humans, all the evidence suggests that wherever this technological development arose it developed in-situ and over a long period of time (see blogs passim). There simply was no "replacement" of one technology by another. Indeed mounting evidence refutes the previously favoured hypothesis which strangely starts from a premise that denies Neanderthals were capable of a range of behaviours observed in modern day humans until presented with overwhelming evidence to the contrary.

Rabbit, rabbit, rabbit, rabbit, rabbit

And again!

New research suggests that archaeologists are leading scientists astray again...

This time, Dr John Stewart Associate Professor in Palaeoecology and Environmental Change from Bournemouth Uinversity heads up a team who have published a paper http://www.sciencedirect.com/science/article/pii/S0047248413000079 apparently demonstrating that in Iberia at least those super smart (but elusive) "modern humans" survived where those "slightly smarter than we'd previously given them credit for" Neanderthals "disappeared". Or something like that.

What the paper hinges on is the idea that stone tool "typologies" can be used as a proxy for cultural or biological markers - which of course they can't. At best they are technological indices, at worst these classifications exist only within the context of Pleistocene archaeology and are not falsifiable. 

What is apparent from the archaeological record - which can no more be expected to be representative of a wider cultural pattern than a household bin might be expected to be - is that stone tools became smaller over time, with a focus on blade production. Where this development has been documented in-situ in regionally diverse areas across Europe, it ranges from as early as 52,000 years ago to as recently as 8,000 years ago and shows no evidence of a "replacement" of one set of humans with another. See comments and references in past blogs for further info.

Picture, blade production at Fontmaure. Top left blade cores. Jasper and Sandstone.

Exhibition @ Watford Museum

Exhibition 9th July to 1st August.

Figure-stones of Fontmaure.

Watford Museum,

194 High Street,

Watford

Hertfordshire

WD17 2DT

Opening times: Thursday-Saturday 10:00-17:00

Free Admission

Not by the hair on your chinny chin chin

New research reported in the Journal of Anatomy from the University of Iowa reaches an unsurprising conclusion: that the development of the chin did not result from mechanical forces such as chewing.


In fact, the prominence of the chin in present day humans is well documented and understood.


"Compared to chimpanzees and macaques, human skulls exhibit a derived spatial distribution of growth fields, especially in the face (Enlow, 1990). While the internal (basicranial) surface of the maxilla grows via interosseous bone deposition (sutural bone growth), the external (facial) surface of the maxilla as well as the external symphyseal area of the mandible exhibit resporptive fields. As an effect, the human face grows inferiorly and anteriorly through maxillobasiocranial bone apposition, but forward growth is counteracted by maxillofacial resportive growth fields. The combination of these processes results in a retracted, vertically oriented face in which the chin represents the most prominent (i.e., least resorbed) part."


Zollikofer C., 2012, Evolution of hominin cranial ontogeny, Progress in Brain Research, 195: 273-289.


Clearly the chin is a neotenous feature but Robert Franciscus from the University of Iowa proposes that it is evidence of so-called "modern humans" replacing "Neanderthals" around 60,000 years ago. Past horizons (http://www.pasthorizonspr.com/index.php/archives/04/2015/our-chins-developed-when-we-started-to-build-social-networks) quote him saying:


"What we’re arguing is that modern humans had an advantage at some point to have a well-connected social network, they can exchange information, and mates, more readily, there’s innovation and for that to happen, males have to tolerate each other. There had to be more curiosity and inquisitiveness than aggression, and the evidence of that lies in facial architecture.”


So in a desperate bid to support the contention that "modern humans" outcompeted or absorbed Neanderthals Franciscus turns incredibly to face architecture. Whilst it is probably correct to imply that the transition from the robust hominins of the past to the gracile hominins of the present day may be in part explained by changing hormone levels (as a result of increasingly culturally mediated mating behaviour for neotenous features) there is no evidence to support the contention that the chin is a feature found only in populations exiting Africa, or indeed that there were well connected social networks exclusive to these groups.

Scott elaborated on her research at the AAPA 2015 conference which refutes the suggestion that the prominent chin observed in extant humans is an autapomorphy upon which to differentiate between "modern humans" and "Neanderthals".
"...this research, demonstrating overlap in overall anterior symphyseal shape between H. sapiens and Neandertals, raises questions about the distinctiveness of the human chin."

http://meeting.physanth.org/program/2015/session39/scott-2015-the-phylogenetic-utility-of-mentum-osseum-morphology-in-pleistocene-homo.html

As noted on numerous occasions on this blog there is no evidence of a "replacement" of Neanderthals in Europe by "modern humans" let alone evidence for the "well connected social networks" that Franciscus refers to. Past Horizons have confused matters further by referring to work that does not support an evidence base for morphological distinction between so called species but rather underlines the key learning: extant autapomorphies are a result of pedomorphosis through neoteny, a heterochronic process.

#FlintFriday

Exhibition 9th July to 1st August.

Figure-stones of Fontmaure.

Watford Museum,

194 High Street,

Watford

Hertfordshire

WD17 2DT

Opening times: Thursday-Saturday 10:00-17:00

Free Admission

#FlintFriday

Exhibition 9th July to 1st August.

Figure-stones of Fontmaure.

Watford Museum,

194 High Street,

Watford

Hertfordshire

WD17 2DT

Opening times: Thursday-Saturday 10:00-17:00

Free Admission

#FlintFriday

Exhibition 9th July to 1st August.

Figure-stones of Fontmaure.

Watford Museum,

194 High Street,

Watford

Hertfordshire

WD17 2DT

Opening times: Thursday-Saturday 10:00-17:00

Free Admission

Oxford University - right behind the mainstream narrative

Stone tool assemblages and models for the dispersal of Homo sapiens out of Africa, 2015, Quaternary International (in press), by Groucutt et al purports to test models for the dispersal of Homo sapiens out of Africa.
https://www.academia.edu/10985350/Stone_tool_assemblages_and_models_for_the_dispersal_of_Homo_sapiens_out_of_Africa
Consider this for a moment. The mostly Oxford based researchers contend that analysis of stone tools can yield information relating to biological or cultural dispersion.
Even if the authors of the paper were able to reliably identify the culture or "species" of human responsible from a given assemblage of stone tools, any analysis concerning the distribution or "pattern of dispersal" would relate only to preservation conditions and chance detection. The idea that a species could be tracked by simply referring to a set of etically described stones is critically flawed and therefore the results are untestable and unscientific.
Any (subjectively) perceived similarities between so called East African lithic assemblages and those from elsewhere is moot in the face of the continuity of in-situ technological development evident from the Middle Palaeolithic into the Upper Palaeolithic at sites throughout Europe.
The assertion that "Most researchers accept that Homo Sapiens evolved in Africa during the late Middle Pleistocene" is argumentum ad populum and ignores the mounting genetic, fossil, stone tool and cultural evidence which refutes it.

#Flintfriday

Hertfordshire Exhibition venue to be announced

Right or wrong?

Published recently by the authors (Holliday, Gautney and Friedl) and Jean-Jaques Hublin (one of the commentators) on Academia.edu is Right for the Wrong Reasons: Reflections on Modern Human Origins in the Post-Neanderthal, 2014, Current Anthropology: 55(6), pp. 696-724.
Genome Era.

https://www.academia.edu/9697813/Right_for_the_Wrong_Reasons_Reflections_on_Modern_Human_Origins_in_the_Post-Neanderthal_Genome_Era

The authors contend that the persistence of Neanderthal genes is more readily explained by the Assimilation (AM) model than the Replacement with Hybridization (RWH) model and reject Multiregional Evolution (MRE).

"We argue this because we reject one of the major tenets of MRE: global gene flow that prevents cladogenesis from occurring. First, using reconstructions of Pleistocene hominin census size, we maintain that populations were neither large nor dense enough to result in such high levels of gene flow across the Old World."

All scenarios suggested for population sizes are at best untestable and at worse entirely fictitious (Bednarik 2013). The failure of many Pleistocene archaeologists to comprehend the implications of taphonomic logic are readily illustrated by the tendency to base these population estimates on the archaeological record. Of course this record is not a record of human population sizes and/or distribution but rather is representative of where the best preservation conditions occur and where researchers have looked. For instance, some estimates assume that there were large unpopulated regions. However, as Bednarik (2013) suggests, a sensible null hypothesis would be to assume that by 45,000 years ago all environments of four continents were as densely occupied as their carrying capacities allowed for. In other words, that there was a contiguous population from Africa to Asia. In such a scenario, following thousands of years of regionalisation reticulate introgression, genetic drift and episodic genetic isolation may all have occurred as suggested by Franz Weidenreich's in 1946. Note that the multiregional model of polycentric  human evolution has diagonal lines (Figure 1) which accommodate these conditions.
The Assimilation theory (AM) concedes the occurrence of genetic exchange between so-called "Neanderthals" and "Modern Humans", i.e. it accepts that they are conspecific - able to produce fertile offspring (Bednarik 2011). AM merely claims an in-flow of African genes. All models of reticular gene flow are in fundamental agreement with the original "trellis" diagram of Weidenreich and AM is no exception however positioned. Wrong isn't right.

Figure 1. Franz Weidenreich's trellis diagram 1946.

What the authors attempt to do is show that these population estimates, which more often than not are simply circular references to the dominant and false Pleistocene archaeological narrative, support the idea that cladogenesis may have occurred - resulting in "modern humans". The duration of time required for reproductive isolation to have occurred is suggested to be in the region of 1 million years and therefore the conclusion of the authors' is at odds with their own estimate as Wolpoff notes in his commentary. They are right and wrong for the right reasons.