Wednesday, August 23, 2017

Who Are The Lebbo' People Of Borneo?

Eurogenes reports that in his efforts to explain the autosomal genetic origins of South Asians that the Lebbo' people of the Indonesian part of the island of Borneo were a better fit to the Ancestral South Asian component of autosomal genetic diversity of South Asians (especially Dravidian speakers) than the Onge people of the Andaman islands who have often been used for that purpose.

This puts front and center the question, "Who are the Lebbo' people of Borneo?"

Two Lebbo' men from this source.

The source for the picture of these two men notes their probably longstanding, pre-Neolithic, presence in the region:
Previous surveys have led to the unexpected discovery of more than 150 caves with unique rock art paintings (mostly hand stencils, Figure 2), dating back to at least the Early Holocene (9900 years BP; Plagnes et al. 2003) and presenting some similarities to those from eastern Indonesian Islands, West Papua and Australia (Fage et al. 2010). These discoveries confirmed for the first time the early human occupation of eastern Borneo. Liang Abu is located 130km north-west of the shore of the Makassar Strait (Figure 1), within the rainforest of a mountainous karstic area (Figure 3). Hundreds of cliff caves and shelters are present, where human activity occurred on three levels: human settlement at the base, burial in the middle and rock art at the top (Chazine 2005). . . . The site is located 6km from the remote Lebbo' village of Merabu. The Lebbo' are an isolated indigenous population of hunter-gatherers and are the only ethnic group which have lived in this inner region for a long time (Figure 5). Ethno-linguistic studies of their oral traditions and cultural practices, to document their former use of caves in relation to the proto-historic and pre-historical periods in the region, are currently under way. Some of the Lebbo's representations can be directly related to the prehistoric rock art found in nearby caves. All these characteristics make Liang Abu a site well suited for the investigation of links between late Pleistocene human occupation, rock art, the communities represented by them as well as the communities of their potential descendants.
The image above is Figure 1 in this article in Nature. The Lebbo' are locating in the Northeast portion of Indonesian Borneo. The Andaman islands, which are home to the Onge are in the chain of Islands extending to the south from Bangladesh to the island of Sumatra (to the west of Myanmar f.k.a. Burma).

The ancestry components of the Lebbo' people based upon a fourteen population admixture analysis (shown in Figure 2 of from the same article, below in bottom panel of the far left) are quite heterogenous, with a plurality component that is most common in Sumatra and Peninsular Malaysia (labeled C13 in the figure below), a significant share of a component that is almost pure in the H'tin people of Thailand (labeled C12), and a notable shares associated with the Ma'anyan people of Borneo (labeled C8, who are linguistically the closest match to the people of Madagascar) and with the people of Sulawesi and the Lesser Sunda islands (labeled C8), but almost none of a Philippine Negrito component (labeled C2), a Hmong component (labeled C7), a component found in the nearby Bidayuh people of Borneo (labeled C9), the Temuan people of Peninsula Malaysia (C10), the Miabei people of Thailand (labeled C5), a West Eurasian component (labeled C6), or an African component (labeled C1).

The same article from Nature also concludes based upon another statistical analysis that mainland Southeast Asia "gene flows reached the west of Borneo, but not the east." But the Lebbo' people are in eastern Borneo (Borneo was, in historic times, divided by a shallow gulf that divided the western and eastern part of the island). An f3-test analysis "showing shared genetic history with Austronesian groups (represented by indigenous Formosan) compared to Mainland Southeast Asian groups (represented by the H’tin)" places the Lebbo' people in an almost overlapping position with the Ma'anyan people (the closest linguistic ancestors of the people of Madagascar), despite their quite different mixes of ancestry components in an Admixture analysis. 

Another analysis, however, puts the Lebbo' equidistant with the Formosan indigenous people from the Ma'anyan people.

In a PCA analysis (Figure 5 in the Nature paper), the Lebbo' people (light gray triangles in a central position on the PCA figure overlapping the green blue and red boxes) are a near perfect match for the Asian component of the ancestors of the people of Madagascar, while the closest linguistic match, the Ma'anyan are clearly not a good match.

There is passing discussion of the Lebbo' who are noted for having some unexpected Austro-Asiatic ancestry in another paper on the current population genetics of the region, and there is more analysis of the genetic data (mostly also discussed in the Nature article) here.

In terms of uniparental genetics, the Lebbo' have the following Y-DNA haplogroups:

C* (13.33%), K* (6.67%), KxLT (13.33%), O2a1 (33.33%), O1a2 (26.67%), and O3a2 (6.67%). This is a subset of the diversity of the Ma'anyan people with one exception understandable given the small sample size.

and the following mtDNA haplogroups:

B4a (21.05%), B5a (15.79%), M20 (15.79%), M71a2 (15.79%), R9b1a1a (10.53%),  and E1a (21.05%). This is about a 50% overlap with the diversity of the Ma'anyan people.

One of the few good references directly discussing the Lebbo' people is a closed access chapter in book of conference proceedings entitled "The Lebbo’ Language and Culture: A Window on Borneo’s Ancient Past" (January 2015), by Antonio Guerreiro, in the book: 12-ICAL Bali, Proceedings volume I, Publisher: ANU, Editors: Wayan Arka, I, pp.149-177. This paper is, however, discussed in a secondary source which recounts that abstract:
The Lebbo’ are former hunter-gatherers/horticulturists; they are localized in remote places in Eastern Borneo, in the regencies of East Kutai and Berau (Province of East Kalimantan). 
Linguistically, they are distinct from the neighbouring Dayak, and Punan (Pnaan) belonging to various branches of the Kayanic and Kenyahic linguistic groups. While the other languages spoken in the region are the Kutai and Berau Malay dialects, besides Bajau and Bugis (on the coastal areas). 
The paper considers the main features and the lexical/phonological aspects of the two Lebbo’ isolects, Lebbo’ Aso’ and Lebbo’ Isi, which amount to less than 1,000 speakers. Both isolects have evolved from the so-called “Basap” language (known also as “Bahasa Sanimban” in Dutch sources). I will relate the Lebbo’ to the other components of this scattered linguistic and cultural group, such as the Ulun Darat (Basap Selatan) in Mangkalihat, the Ulun Latti in Northern Berau and related Basap in Talisayan. Until now the Lebbo’ language has not been recorded and described systematically. 
In central Borneo, the ancient links of the Lebbo’ are to be found with the proposed Rejang-Sajau linguistic group (Hudson 1978). These links, spread across the Island, point to other languages from East to Western Borneo. The field research was carried from 2009 to 2011 in the frame of the French-Indonesian pluridisciplinary programme, and supplemented by the study of archival materials.
Another story (in Spanish) advocating for designation of parts of their homeland as a UNESCO World Heritage site notes (via Google translation of the Spanish) that:
In karst, thick tropical forests conceal the worn limestone towers, among which the team discovered 35,000-year-old bones and charcoal, the oldest test of human occupation found so far in Kalimantan. "These remains are interesting because for a long time Kalimantan was excluded from the history of human evolution." . . .
The Franco-Indonesian team is working in an area where ancient peoples left impressions of their hands in caverns 10,000 years ago or more. In addition to ancient bones, they found hundreds of rock paintings in orange to brown pigments showing figures of tapirs (now extinct in Borneo), wild cattle and some creatures unknown to us today. 
The wonders of the Sangkulirang-Mangkalihat karst are not limited to the human footprint: the southeastern limestone hills and valleys of Southeast Asia have been called "biodiversity coffers" in danger. The region abounds in rare species restricted to limestone. "I saw blind freshwater fish, rare bats, black and white swifts, innumerable animals. It is also a refuge for orangutans fleeing forest fires during the El Niño years," explains biologist Rondang Siregar of the University of Indonesia. 
The diversity of species of bats is greater than in any point of Southeast Asia. Also discovered cockroaches of a species endemic to a cave and that with its 10 centimeters is the largest in the world. 
About 2,000 Lebbo live in the region, the only ethnic group that inhabits this inland part of eastern Borneo. The Lebbo incorporate to their narrations elements of the cave paintings. One of his myths speaks of a young shaman and his eight wives who took possession of the Karst territory marking the caves with paintings of their hands, as was done in the caves millennia ago. 
The Lebbo have been a great help since they know the karst and the forest and collaborate in the location of the shelters and interpret the paintings.
A DVD recounting of the story of the Shaman is available. See also this description of those materials:
A Lebbo' Shaman's Tale 
During the first part of the interview, Pak Kuling, a Lebbo' shaman (belian) from the village of Pana'an (aged about 50), who is currently the kepala adat, tells of the feats of Belian Danyam. Belian Danyam, literally, "The Young Shaman," is a culture hero of the Lebbo' people of the Lesan River area of East Kalimantan. Among the villagers the hero's legacy remains alive to this day. Several important aspects of this narrative are stressed. Generally, the narrative focuses on the idea of territorial origins and shamanic powers. Belian Danyam was miraculously born as a shaman among human beings on earth. However, who his parents were is not known. As a child he was ready to practice rituals at once and did not have to study first with an elder shaman as is usually the case. During his travels and adventures in the Karst region, the hero expelled evil spirits from the earth, thus making it a suitable place for humans to live. Because he was jealous of his eight wives' behavior, he broke the taboo against mocking animals and so had to cope with the anger of the powerful Thunder God, Meruaa Laut, the protector of adat. Eventually, in his flight the hero vanished into a mountain named Batu Lujep located at the headwater boundary of the upper Lesan and Tabalar Rivers. After his disappearance into the rock his seven successors, known by their shamanic titles, continued to perform in the shamanic tradition (adat belian) he instituted. 
It was Belian Danyam's eight wives who made the stencils of their hands and other marks in the caves as a sign of "being there" and of taking possession of the surrounding area. The hero thus produced a social space in this remote Karstic region. Perhaps, this aspect of the narrative can be related to the holistic character of Lebbo' shamanistic representations, involving the forested landscape and the plentiful reproduction of natural resources (fruits, honey, game). Conversely, a feature that is prevalent in the tale is the notion of bounded territories ascribed to Lebbo' local groups. Spatial boundaries are well-known and relate directly to natural resource exploitation within local group territories. 
In the second part of the interview, Pak Ruling describes ritual ideas and practices at the core of Lebbo' shamanism, i.e. the Tuak harvest festival and the Nobet curative/ purification rites.
Not much is known about their languages, as explained in the link to a presentation describing an effort to document these languages:
The project is focussed on documenting the oral traditions and compiling bilingual vocabularies of some former hunters-gatherers’ languages in the Province of East Kalimantan. Until now these languages, mainly the Punan Tubu’ and the Ulun Lebbo’ and Ulun Darat are poorly known and scattered in different Regencies. The topics addressed in this documentation project are: 
• oral traditions (songs, epics, stories, myths, proverbs); 
• linguistic interactions and borrowings, phenomenon of diglossia with the National language (Bahasa Indonesia), and other, regional, languages; 
• lexicology and dialectal variations. 
• Very little information on the oral traditions of these people is available. 
• The main kind of narrative genre is mbui. 15 mbui have been collected and 8 have been transcribed and translated. A dictionary is being prepared and will be published together with the stories and their translations in Indonesian. 
Many languages from multiple only modestly related language families are spoken in the region, although all are apparently Austronesian languages, albeit with substrate influences probably from Austro-Asiatic languages which are common in mainland Southeast Asia.

The Lebbo' peoples historic range may have been more expansive than it is today.

Monday, August 21, 2017

The 2017 Solar Eclipse In Denver

The 93% solar eclipse in Denver was still surprisingly bright (like a heavily overcast day, much more than moonlight), but discernibly cooler than normal, despite the high fraction of the sun obscured as seen with eclipse glasses.

The relevant physics have been known since the 1600s, and eclipses were predicted by cruder means even back in the late 1400s. So, there was nothing new to learn on that front.

In short, slightly better than meh. It was a fun minor social event.

CMB Constraints On Axion Dark Matter

There is no evidence of axion dark matter in its most natural mass range, which implies that axion dark matter is not a plurality contributor to dark matter and probably makes up only a small percentage of it, if it exists at all. 
The cosmic microwave background (CMB) places strong constraints on models of dark matter (DM) that deviate from standard cold DM (CDM), and on initial conditions beyond the scalar adiabatic mode. Here, the full Planck data set (including temperature, E-mode polarisation, and lensing deflection) is used to test the possibility that some fraction of the DM is composed of ultralight axions (ULAs). This represents the first use of CMB lensing to test the ULA model. We find no evidence for a ULA component in the mass range 1033ma1024 eV. We put percent-level constraints on the ULA contribution to the DM, improving by up to a factor of two compared to the case with temperature anisotropies alone. 
Axion DM also provides a low-energy window onto the high-energy physics of inflation through the interplay between the vacuum misalignment production of axions and isocurvature perturbations. We perform the first systematic investigation into the parameter space of ULA isocurvature, using an accurate isocurvature transfer function at all ma values. We precisely identify a "window of co-existence" for 1025 eVma1024 eV where the data allow, simultaneously, a 10% contribution of ULAs to the DM, and 1% contributions of isocurvature and tensors to the CMB power. ULAs in this window (and all lighter ULAs) are shown to be consistent with a large inflationary Hubble parameter, HI1014 GeV. The window of co-existence will be fully probed by proposed CMB-S4 observations with increased accuracy in the high- lensing power and low- E and B-mode polarisation. If ULAs in the window exist, this could allow for two independent measurements of HI in the CMB using the axion DM content and isocurvature, and the tensor contribution to B-modes.
Renée Hlozek, David J. E. Marsh, Daniel Grin "Using the Full Power of the Cosmic Microwave Background to Probe Axion Dark Matter" (August 18, 2017).

From the introduction in the body text:
A central role in the standard cosmological model is played by Cold Dark Matter (CDM). Using a combination of temperature (T), E-mode polarisation, and weak gravitational lensing power spectra of the CMB, the CDM density is measured to be
Ωch^2 = 0.1199 ± 0.0022 (Planck Collaboration et al. 2016b). CDM is the only form of Dark Matter (DM) required by the data, providing the backbone of the “cosmic web” of large scale structure on linear scales.  
One well-motivated theoretical possibility for the CDM is the axion, a new hypothetical particle motivated by the charge-parity conjugation problem of quantum chromodynamics (QCD) (Peccei & Quinn 1977; Weinberg 1978; Wilczek 1978; Abbott & Sikivie 1983; Dine & Fischler 1983; Preskill et al. 1983). On scales of relevance to cosmology, QCD axions with mass ma < 10^−4 eV are produced non-thermally, have the correct cosmological relic density, and behave as CDM.  
There are very few direct constraints on the QCD axion CDM parameter space (e.g. Asztalos et al. 2010). The lightest supersymmetric particle also provides a canonical CDM candidate (Jungman et al. 1996), though limits on “natural” regions of its parameter space are strong (e.g. Akerib et al. 2017).  
The CMB places stringent limits on a variety of theoretical models for DM beyond CDM, including limits on the mass of standard model neutrinos (Planck Collaboration et al. 2016b), thermal axions (Archidiacono et al. 2013), DM interactions (Wilkinson et al. 2014b; Wilkinson et al. 2014a), and generalized models (Cyr-Racine et al. 2016; Thomas et al. 2016).  
A particularly interesting bound comes from constraints on non-thermally produced ultralight axions (ULAs), as this establishes an absolute lower-bound on the DM particle mass from linear observables, ma > 10^−24 eV (Hlozek et al. 2015). The constraints of Hlozek et al. (2015) (hereafter, H15) not  only bound the particle mass of the dominant component of DM, but also place stringent limits on the axion DM density over many orders of magnitude in particle mass (10^−33 eV < ma < 10^−24 eV) for models in which the DM is a mixture of “standard” CDM and ULAs.  
Cosmology thus probes not only the abundance but also the composition of the dark sector. ULAs are expected to be ubiquitous in string theory (e.g. Svrcek & Witten 2006; Conlon 2006; Arvanitaki et al. 2010) and provide candidates for dark matter (if ma > 10^−27 eV) or dark energy (if ma > 10^−27 eV) components, depending on their mass. 
For fairly natural values of the axion initial field value in string models, φ¯ i ∼ fa < 10^17 GeV, where fa is the axion “decay constant”, ULAs contribute at the percent level to the cosmic critical density (Marsh 2016; Hui et al. 2017).[1]  
[1] The boundary between the two regimes is a matter of convention. Here it has been chosen as approximately the inverse Hubble parameter at matter radiation equality.
Within the range of particle mass (10^−33 eV < ma < 10^−24 eV) the axion ULA percentage of all mass-energy in the universe in the mid-range is most likely about one part per thousand and definitely not more than one part per hundred. It could potentially be almost 10% at the high end of 10^-24 eV with the high end of the error bars (less than half that at 10^25 eV), where it almost reaches a CDM threshold, and potentially even more at the extreme 10^-33 eV low end (almost totally absent at 10^-32 eV) where there is degeneracy between dark matter and dark energy contributions allow it to hit 20.3% of the total mass-energy of the universe.

The bottom line is that there are strict experimental constraints from the CMB on axion dark matter, and it is basically ruled out for many orders of magnitude of particle mass as the sole component of dark matter. Another recent study also disfavored axion dark matter. More constraints on axion dark matter from cosmology observations are here. QCD evidence suggests that if axions exist that they should be heavier than the ULA mass range (see also here).

This matters, of course, because experimental and observational evidence is increasingly ruling out dark matter particle candidates.