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The Trials and Tribulations of Homo floresiensis: A Quick Introduction

1 Sep

I haven’t wrote about palaeoanthropology much recently, but I have been meaning to write about Homo floresiensis for a while now.  The diminutive hominin, most likely a new Homo species although this is still debated, was discovered by chance on the Indonesian island of Flores in 2003 during the excavation of the Liang Bua cave site, which was led by the now sadly deceased New Zealand archaeologist Mike Morwood (Brown et al. 2004).  The team that excavated at Liang Bua cave found the remains for a probable 12 separate H. floresiensis individuals dating from around 95,000 years ago to around 13,000 years ago (1), making H. floresiensis one of the last hominin species to live in conjunction with our species, H. sapiens (Brown et al. 2004: 1055).  One of the most complete individuals found at the site is LB1, an adult female aged around 30 who has almost both lower limbs, upper right arm, pelvis and cranium surviving (see image below).  It is this individual that has become the holotype, or type species, for H. floresiensis and on who most of the current research has, and continues, to focuses on (Brown et al. 2004, Brown 2012, Falk et al. 2005, Henneburg et al. 2014).

The majority of this research has been focused on the skeletal remains themselves and archaeological context as attempts to extract ancient DNA (aDNA) from the remains has not been successful, likely due to the cave environment that the skeletons were excavated from and the fragmentary nature of the surviving aDNA.  Morwood’s team formally announced the details of the skeletal remains in 2004 and stated that the remains included primitive and derived features resulting from long term isolation and endemic dwarfing (Brown et al. 2004: 1055-56).  It is important to note here that up until the excavation of H. floresiensis in 2003 it was thought that only H. erectus and H. sapiens were the only Homo hominins present in Late Pleistocene Asia (Brown et al. 2004: 1056).  Later hominin finds, such as at the Denisova Cave excavations in Siberia in 2010 and the announcement of the Denisovan species, have highlighted that other unknown hominins were present in Late Pleistocene Asian contexts helping to fundamental change, and challenge, the way that we think of the evolution of our species H. sapiens (Reich et al. 2010: 1053).

LB1

The species holotype is LB1, found in 2003 in the Liang Bua cave site on Flores, Indonesia. The adult female individual dates to 18,000 years old, stood 3.5 ft tall and represents one of the most complete H. floresiensis individuals found. Notice the large dentition relative to the overall cranium size. Image is not to scale. Image credit: Jennifer Clark (Human Origins Program) and Chip Clark (Smithsonian Institution).

There are many issues surrounding the remains of the H. floresiensis hominins that serve to obstruct and help obfuscate the research that has taken place into understanding the origin and anatomy of the floresiensis hominin.  Inevitability this is ongoing as McVie (2014) highlights in a recent Guardian newspaper article.  Thus it is pertinent to highlight them here to help understand where we are at with understanding the remains of the Flores hominin.  Indeed the H. floresiensis case has all the unfortunate tropes of a spectacular palaeoanthropological find (2) (the unexpectedness of the finds, the bickering academics, mishandling of remains etc.) and continues to show no sign of abating.

As is indicative above, H. floresiensis is a unique and interesting recent hominin ancestor, even more so as the only physical remains of the species are the 12 individuals found and excavated at the Liang Bua cave site in Indonesia.  It is the opposite to our modern notion of the (much maligned) Neandertal, being gracile, petite and small in statue and body.  Perhaps inevitably it was labelled a ‘hobbit’ species (although this word has led to problems with the Tolkein estate).  The type specimen LB1 was quickly repudiated as a H. sapiens individual with a pathology by several researchers and others who have, at various times, stated that all the H. floresiensis individuals, and in particular LB1 and partial skeleton LB6, display attributes varying from myxoedematous endemic cretinism (Oxnard et al. 2010, Brown 2012), Laron Syndrome (Falk et al. 2009, see Hawks 2007), or Down Syndrome (Benton 2014, Henneburg et al. 2014).  There have also comparisons even being made of the singularity of the Late Pleistocene epoch species being compared to the K/T impact boundary event 65 million years ago (Eckhardt et al. 2014), which frankly is a little mystifying.

McVie (2014) has highlighted a potential conflict of interest with regards to both the Eckhardt et al. (2014) and Henneburg et al. (2014) publications, as there is a suggestion that Henneburg (who helped author both articles) picked his reviewers to help favour his research team’s hypothesis and investigation.  The journal that both of the articles were recently published in, Proceedings of the National Academy of Sciences of the United States of America (or PNAS), does not operate a peer review policy in the recognised sense, as most of the other respected journals use, but uses its own specific and trusted system (see here).  Perhaps most surprising is the fact that this team have now published 3 separate papers each focusing on different pathological conditions each time in their continued belief that the H. floresiensis remains are probable members of H. sapiens and represent pathological processes (Henneburg et al. 2014).

Regardless of the ongoing new-species-or-not debate there must be further investigation of the context of the remains.  As Hawks (2007) highlights it is the exact nature of where H. floresiensis fits in both the evolutionary tree and the archaeological context of Asia that remains to be thoroughly demonstrated.  This can only be determined by further finds with consolidated archaeological contexts over an extensive period of time and, with luck, further specimens of this hopeful new species.  The specimens of this population found on Flores, Indonesia, are both tantalising for the human evolution implications and frustrating for their apparent uniqueness in location and time.  As such the Flores H. floresiensis remains are surely one of the most interesting and divisive points of interest in the palaeoanthropological world today.

Notes

(1). A new analysis of the chosen radiocarbon samples and the stratigraphy of the cave site by Sutikna et al. (2016) has led to a serious revision in the chronology of the Homo floresiensis fossils.  It seems that all fossil evidence of H. floresiensis is older than 60,000 years, which is a major revision and leaves a lot of questions regarding the contextual material culture and faunal remains and their association with the fossil hominins.  John Hawks has covered the implications that this new article by Sutikna et al. has in a detailed and interesting read, check it out here.

(2). An excellent counter example of this is the University of the Witwatersrand and National Geographic funded Rising Star project currently underway in South Africa, where the remains of a spectacular palaeoanthropological site (with the evidence of numerous hominin individuals of some importance) has been well and truly open to researchers and members of the public to take part in and to learn about.  This has included an extensive and on-going social media presence and an open call for researchers to join collaborative workshops to study the remains.

Lean More

  • The Smithsonian Institute has a handy guide in introducing the hominins of human evolution at the Human Origins website and, as a part of this, there is a nice guide to H. floresiensis.
  •  For a full round of the issues involved in the research of H. floresiensis and the LB1 type fossil, I highly recommend reading the Wikipedia entry on the species which covers all pertinent academic articles published.

Bibliography

Benton, A. 2014. Was the “Hobbit” a Human with Downs Syndrome? Probably Not. EvoAnth. Accessed 19/08/14. (Open Access).

Brown, P. 2012. LB1 and LB6 Homo floresiensis are Not Modern Human (Homo sapiens) Cretins. Journal of Human Evolution. 62 (2): 201-224.

Brown, P., Sutikna, T., Morwood, M. J., Soejono, R. P., Jatmiko, Wayhu Saptomo, E. & Rokus Awe Due. 2004. A New Small-Bodied Hominin from the Late Pleistocene of Flores, IndonesiaNature. 431 (7012): 1055–1061.

Eckhardt, R. B., Henneburg, M., Weller, A. S. & Hsu, K. J. 2014. Rare Events in Earth History Include the LB1 Human Skeleton from Flores, Indonesia, as a Developmental Singularity, not a Unique Taxon. PNAS. 111 (33): 11961-11966. (Open Access).

Falk, D., Hildebot, C., Smith, K., Morwood, M. J., Sutikna, T., Brown, P., Jatmiko, E. W. S., Brunsden, B. & Prior, F. 2005. The Brain of LB1, Homo floresiensis. Science. 308 (5719): 242-245.

Falk, D., Hildebolt, C., Smith, K., Jungers, W., Larson, S., Morwood, M., Sutikna, T., Jatmiko, E. W. S. & Prior, S. 2009. The Type Specimen (LB1) of Homo floresiensis Did Hot Have Laron Syndrome. American Journal of Physical Anthropology. 140 (1): 52-63.

Hawks, J. 2007. Another Diagnosis for a Hobbit. John Hawk’s Weblog. Accessed 24/08/14. (Open Access).

Henneberg, M., Eckhardt, R. B., Chavanaves, S. & Hsu, K. J. 2014. Evolved Developmental Homeostasis Disturbed in LB1 from Flores, Indonesia, Denotes Down Syndrome and Not Diagnostic Traits of the Invalid Species Homo floresiensis. PNAS. Early View: 1-6. (Open Access).

McKie, R. 2014. Homo floresiensis: Scientists Clash Over Claims ‘Hobbit Man’ was Modern Human with Downs Syndrome. The Guardian. Accessed 19/08/14.

Oxnard, C., Obendorf, P. J. & Kefford, B. J. 2010. Post-Cranial Skeletons of Hypothyroid Cretins Show a Similar Anatomical Mosaic as Homo floresiensis. PLoS ONE. 5 (9): 1-11. (Open Access).

Reich, D., Green, R. E., Kircher, M., Krause, J. Patterson, N., Durand, E. Y., Viola, B., Briggs, A. W. & Stenzel, U. et al. 2010. Genetic History of an Archaic Hominin Group from Denisova Cave in Siberia. Nature. 468 (7327): 1053–1060. (Open Access).

Sutikna, T., Tocheri, M. W., Morwood, M. J., Saptomo, E. W., Awe, R. D., Wasisto, S. … & Storey, M. 2016. Revised Stratigraphy and Chronology for Homo floresiensis at Liang Bua in Indonesia. Nature. In Press. doi:10.1038/nature17179.

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Neolithic Craftsmanship In Central Europe

22 Jan

A recent paper by Tegel et al. (2012) demonstrates the intricate wood crafting abilities of the Neolithic Linearbandkeramik culture, known as the LBK, in the construction of water wells from planks of wood dated from 5500 BC to 5098 BC.  From the analysis of four wooden wells, and a total of 151 oak timbers from the wells, the precise history of their construction can be confirmed.  This is exciting news as it is firsthand evidence from a range of LBK sites of the carpentry skills, as practiced by the builders, that were apparent during the culture’s existence.  The LBK are typically known as one of the first major European cultures that helped spread agriculture via a number of different mechanisms (Bogaard et al. 2011), and are noted for their use of  cemeteries (Zvelebil & Pettit 2012), differential deposits of shoe last adzes in graves, and uniformity of small settlements and clustered long houses throughout Central Europe, although tantalizingly little remains of their famous long houses.

Bentley et al. (2012) have recently delved into extensive strontium isotope testing of cemetery populations and have released a slew of papers suggesting that, due to different ratios in the presence of male and female adult individuals, the LBK culture practiced patrilocality, i.e. that women moved around to other sites to start families or join different villages, whilst the fathers and sons largely stayed within their birthplace landscape.  Although it should be noted that there are some regional differences, with certain populations practicing transhumance with cattle, possibly moving with them throughout a varied landscape (Rasteiro et al. 2012).  Furtheer to this, there has been little coverage or investigation of infant or juvenile remains in the LBK culture, and this is a research bias that is similar to the under-consideration of of such populations in the wider Neolithic archaeological record (Lillie 2008).

journal.pone.0051374.g004

A detail from some from some of the water wells excavated from sites in Eastern Germany that were used in the dendro-chronological analysis and reconstruction (Tegel et al. 2012: 2). The majority of the wells were block lifted from their Neolithic period excavation sites and micro-excavated in wet lab conditions to allow preservation, greater photographic resolution, laser recording and stratigraphic recording. A reconstruction of their wooden joints was possible, because of this technique and the care taken to preserve the wood in-situ.

Article Abstract:

“The European Neolithization ~6000−4000 BC represents a pivotal change in human history when farming spread and the mobile style of life of the hunter-foragers was superseded by the agrarian culture. Permanent settlement structures and agricultural production systems required fundamental innovations in technology, subsistence, and resource utilization. Motivation, course, and timing of this transformation, however, remain debatable. Here we present annually resolved and absolutely dated dendroarchaeological information from four wooden water wells of the early Neolithic period that were excavated in Eastern Germany. A total of 151 oak timbers preserved in a waterlogged environment were dated between 5469 and 5098 BC and reveal unexpectedly refined carpentry skills. The recently discovered water wells enable for the first time a detailed insight into the earliest wood architecture and display the technological capabilities of humans ~7000 years ago. The timbered well constructions made of old oak trees feature an unopened tree-ring archive from which annually resolved and absolutely dated environmental data can be culled. Our results question the principle of continuous evolutionary development in prehistoric technology, and contradict the common belief that metal was necessary for complex timber constructions. Early Neolithic craftsmanship now suggests that the first farmers were also the first carpenters.”

Read more here.

Below are further sources to delve into the intriguing LBK culture.

Bibliography and Further Sources:

Bentley, R. A., Bickle, P., Fibiger, L., Nowell, G. M., Dale C. W., Hedges, R. E. M., Hamiliton,. J., Wahl, J., Francken, M., Grupe, G., Lenneis, E., Teschler-Nicola, M., Arbogast, R-M., Hofmann, D. & Whittle, A. 2012. Community Differentiation and Kinship Among Europe’s First Farmers. Proceedings of the National Academy of Sciences Early Edition. doi:10.1073/pnas.1113710109. 1-5.

Bogaard, A., Krause, R. & Strien, H.-C. 2011. Towards a Social Geography of Cultivation and Plant Use in an early Farming Community: Vaihingen an der Enz, South-West Germany. Antiquity. 85: 395-416.

Bramanti, B., Thomas, M. G., Haak, W., Unterlaender, M., Jores, P., Tambets, K., Antanaitis-Jacobs, I., Haidle, M. N., Jankauskas, R., Kind, C.-J., Lueth, F., Terberger, T., Hiller, J., Matsumura, S., Forster, P & Burger, J. 2009. Genetic Discontinuity Between Local Hunter-Gatherers and Central Europe’s First Farmers. Science. 326 (5949): 137-140.

Lillie, M. C. 2008. Suffer the Children: ‘Visualising’ Children in the Archaeological Record. In: C. Barcvarov (ed.) Babies Reborn: Infant/Child Burials in Pre- and Protohistory. Conference Proceedings, UISPP, Lisbon. BAR International Series. 1832. Oxford: Archaeopress. pp. 33-43.

Rasteiro, R., Bouttier, P., Sousa, C. C & Chikhi. 2012. Investigating Sex-biased Migration During the Neolithic Transition in Europe, Using an Explicit Spatial Simulation Framework. Proceedings of the Royal Society B Biological Sciences. Doi:10.1098/rspb.2011.2323 accessed on the 20th of May 2012.

Tegel W., Elburg R., Hakelberg D., Stäuble H. & Büntgen U. 2012. Early Neolithic Water Wells Reveal the World’s Oldest Wood ArchitecturePLoS ONE. (12): 1-8. e51374. doi:10.1371/journal.pone.0051374

Vanmontfort, B. 2008. Forager-Farmer Connections in an ‘Unoccupied’ Land: First Contact on the Western Edge of LBKTerritory. Journal of Anthropological Archaeology. 27 (2): 149-160.

Zvelebil, M. & Pettitt, P. 2012.  Biosocial Archaeology of the Early Neolithic: Synthetic Analyses of a Human Skeletal Population from the LBK Cemetery of Vedrovice, Czech Republic. Journal of Archaeological Science. In Press.

The Origins of Tuberculosis & Smallpox

3 Jun

The following articles cited were brought to my attention by the good work of Confusedious: A Science Blog, and his entries on TB and its  possible origin.

Surprising Origins of Tuberculosis & Smallpox

Recent genetic investigations into the origin of the above diseases, of the chromosomes in TB and the study of smallpox’s ‘biological clock’, has revealed interesting information regarding their origin.   TB and Smallpox were previously thought caused or at least had its early origins during the domestication of animals, and by the dense urbanisation of human populations, first seen during the Mesolithic to Neolithic transition (Tuberculosis- Barnes et al 2011, Larsen 1997, Roberts & Manchester 2010, Smith et al 2009, Smallpox- Li et al 2007, Waldron 2009).

Compression Of Vertebrae As An Effect Of TB

Tuberculosis was originally thought to be spread from bovine at the period of domestication, with the strains M. Tuberculosis and M. Bovis to be considered the main organisms for TB infection in humans.  New genetic research has led to distinguish that M. Tuberculosis did not evolve from M. Bovis at the time of domestication of animals as a direct zoonosis; however it must be remembered that ‘it is probable that a necessary condition for its transference from animal to human is the close association between the two’ (Roberts & Manchester 2010: 184, Smith et al 2009).  I’d imagine the intensification of the Neolithic domestication undoubtedly led to higher rates of cross-species infection.  Research has also shown that the Mycobacterial Tuberculosis strain appeared some 15,300-20,400 years ago, well before the domestication of the earliest animals (Roberts & Manchester 2010: 185).  However there is no doubting the record that during the Neolithic, and up to the present day, that TB has damaged numerous lives.  The effects of TB on the human body can produce results found in osteological remains (Waldron 2009).  This will be discussed in a later blog entry on diseases found in human bones.

The threat of smallpox, a unique infectious disease to humans, was wiped out in AD 1980, but its origins are mysterious.  As Roberts & Manchester (2010: 181) note smallpox (Variola major or minor) ‘would obviously need highly populated urban areas for its success…and it is unlikely it was a problem until urbanization occurred’.  Recent genetic investigations into the origin of the Variola major/minor have discovered that it likely diverged from an ancestral African rodent-borne Variola-like virus either 68,000 to 16,000 BP (Li et al 2007).  However, it is well known that in its most virulent form in humans as smallpox, it has ravaged human urbanised populations for at least 2000 years, and is definitely dated to 10,000 BP.  Curiously, from documentary data and archaeological data, it seems there is a particular lacking of recorded smallpox cases in ancient Greece and ancient Rome (Roberts & Manchester 2010).

The Effects of Smallpox Decimated The Americas When The Europeans Helped Spread the Disease in the 16th Century, As Depicted In This, The Florentine Codex.

New genetic data is providing the backdrop for how infectious diseases spread, and more about their origin.  It is also helping scientists develop past population pathways for infection routes and rates (Jurmain et al 2011).It is apparent that new genetic data has opened up a whole raft of new research potentials into the origins and evolution of tuberculosis, and the relationship before, during and after the domestication of animals.

Bibliography:

Barnes, I.Duda, A. Pybus, O. G. Thomas, M. G. 2011. ‘Ancient Urbanization Predicts Genetic Resistance To Tuberculosis’. In Evolution. 65 (3): 842-848. Blackwell Publishing: London.

Jurmain, R. Kilgore, L. & Trevathan, W.  2011. Essentials of Physical Anthropology International Edition. London: Wadworth.

Li, Y. Carroll, D. S. Gardner, S. N. Walsh, M C. Vitalis, E. A. & Damon, I. K. 2007. ‘On The Origin of Smallpox: Correlating Variola Phylogenics with Historical Smallpox Record’. In PNAS. 104 (40). October 2nd.  15,787-15,792.National Academy of Sciences: Wisconsin.

Roberts, C. & Manchester, K. 2010. The Archaeology of Disease Third Edition. The History Press: Stroud.

Smith, N. H. Hewinson, R. G. Kremer, K. Brosch, R. & Gordon, S. V. 2009. ‘Myths and Misconceptions: The Origin and Evolution of Mycobacterium tuberculosis’. In Nature Reviews: Microbiology. Vol 7. 537-544. Macmilan Publishers Limited: London.

Waldron, T. 2009. Palaeopathology: Cambridge Manuals in Archaeology. Cambridge:Cambridge University Press.