The ‘Black Hole’ of Palaeoanthropology

Archaeology, Archeology, Human Evolution, Human Origins, Palaeoanthropology, Palaeontology, Paleoanthropology, Paleontology
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The ‘Black Hole’ of Palaeoanthropology is not a term you hear very often, but then again what is there to say about the biogeographic history of a 1.77 million square kilometer region (Turkey, Saudi Arabia, and Iran) with virtually no faunal, human or archaeological sites. At this point it would seem easy to resign yourself to the words of Timothy D. White at the dawn of the 21st century, that we are not going to find many more fossil hominins. The mark of a great palaeoanthropologist is to never give up that curiosity for the unknown. Since White’s depressing prediction, he has been roundhouse kicked to Wrongville, with the spectacular finds of Ethiopia, South Africa, Myanmar, China, Flores and much much more. We have learned so much thus far, don’t lets forget this. Sounds great but these inevitably throw up more questions than answers. And the ‘Black hole’ is a particularly hard nut to crack. 

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What does archaeology have to offer? Ethiopia features the earliest concrete evidence for hominin stone tool manufacture. At 2.6 million years of age it predates the earliest known human – Homo habilis – by less than 300,000 years years (Fossil Code: A.L. 666). Saudi Arabia has a rather rich representation of Mode 1 (Oldowan) stone tool clusters. If you don’t know to millimeter accuracy where the stone tool was found, or if it is a surface find then it is worthless to science.  The Saudi sites were also used during the Holocene (11,700 years ago to present), begging the question how can you separate Early Pleistocene (2.5 million years ago to 700,000 years ago) from Holocene activity? At least we can tell that hominins took one route out of Africa. Stone tools similar to the Oldowan found at Perim Island supports the hypothesis that early hominins crossed the Bab al Mandab Strait (20 miles wide). Iran has probably the most depressing lack of archaeological evidence of the region. Isolated finds dominate, both the Oldowan and Acheulean records of Iran and few excavations have taken place. South of the Caspian Sea is the site of Ganj Par, which yielded 100 limestone tools within half a hectare. This assemblage shares similarities with those of Ubediya, Israel and the Oldupai Gorge (also known as the Olduvai Gorge), Tanzania. Turkey repeats much the same story. Of the 200 Palaeolithic sites, less than 25 have been even partially excavated. The majority are restricted to the fringes of the Anatolian plateau.  None are any older than 1.3 million years of age, further supported by Argon-Argon dating of Kula, western Turkey to 1.24 million years of age. The site was the location of a palaeomeander which contained a solitary Quartz flake, 5 x 4 cm. Volcanic activity interfered with the palaeomeander and it was that lava flow that allowed the date to be so accurate. The take-home-message from Turkey is the earliest securely dated archaeological remains support the 1.1 million years calculated for the Kocabas skullcap, which shares affinities with OH 9 and KNM ER 3733, attributed to H. erectus. Debate continues as to its taxonomic status, but it does reflect a great deal of H. erectus characteristics. The Archaeology tells us that hominins with the ability to make stone tools were already out of Africa 1.8 million years ago, at the site of Dmanisi, Georgia.

It is the richest fossil hominin location at the ‘black hole’ fringe. The Fall of 2013 was just another milestone in sites long history of archaeological investigation. The discovered cranium (D4500) was reunited with its jaw (D2600) and the team of palaeoanthropologists led by David Lordkipandize  concluded that the five individuals represented members of the same species, but retracted the classification of D2600 (Homo georgicus) for Homo erectus ergaster georgicus. This raised some eyebrows in the palaeoanthropological community, particularly Fred Spoor, palaeoanthropologist and lecturer at the UCL Department of Anthropology,  who pointed out that such an action is not outlined in the code of zoological nomenclature. This is a minor debate in the palaeoanthropology, but most agree that Homo erectus exhibited a variation comparable to that seen in modern Homo sapiens today. Dmanisi is proof that hominins were already out of the African continent by 1.8 million years. Additionally, although the dating of the hominins of Java are in the doldrums, these specimens could be as much as 1.8 million years of age. Prior to that time some hominin species made it’s way north, but which one?

Dmanisi, Georgia on the fringe of the palaeoanthropological 'Black Hole'
Dmanisi, Georgia on the fringe of the palaeoanthropological ‘Black Hole’

On the 23rd of January 1995, a French-Chadian team of palaeontologists discovered a fragment of fossil jaw (Fossil Code: KT 12/H1) lying on the gravel desert of northern Chad. The fossil (nicknamed “Abel”) could not be accurately dated, nevertheless stratigraphic layers nearby suggested it could as much as 3.5 million years of age. Back then, the river Bahr El Ghazal flowed into a 3 million square kilometer lake called Megachad.  This hominin foraged on grasses that dominated the Koro Toro region. The palaeontologists gave “Abel” a new species name – Australopithecus bahrelghazali distinguishing it from another australopithecean – Australopithecus afarensis. That species lived in the eastern region of the continent, over 2,500 km from the Bahr El Ghazal site. The animal remains found in the stratigraphic layers of both regions were pretty much identical, which means the ecosystems were the same. Therefore, you can see why some palaeoanthropologists consider it plausible that “Abel” is just another Au. afarensis. This goes back to the argument that, what we are looking at here is just another variation of the same species. Either way, here we have australopitheceans in eastern and north central Africa. Theoretically, it is plausible for australopitheceans to have made their way into Arabia.

Chadian Basin: The blue outlines the rough shape and size of Megachad. Note that KT 12/ H1 was uncovered at the site indicated as "KT".
Chadian Basin: The blue outlines the rough shape and size of Megachad. Note that KT 12/ H1 was uncovered at the site indicated as “KT”. (Lebatard et al – 2010 – Application of the authigenic 10Be/9Be dating method to continental sediments: Reconstruction of the Mio-Pleistocene sedimentary sequence in the early hominid fossiliferous areas of the northern Chad Basin)

Every organism has a landscape format that they thrive within. Lions are quite at home in the savannah, Tigers frolick in the dense jungles of the Indian subcontinent and hominins, particularly australopitheceans, were quite at home in savannahs. If we are to prove that they made their way into Arabia, there should be an extension of savannah into the Eurasia 3-4 million years ago. Sadly we are not seeing this, but what do we see. The faunal record of Saudi Arabia is particularly fragmented and sparse. Western Turkey (Calta) 2.3 million years ago, saw Raccoons, Giraffes, Hippos and the extinct “Running” Hyena. Many associate Bethlehem with the Christian story, but few know that at about the same time, this region featured Raccoons, Sabre-Toothed Cats, Rhino, an ancestor to the Mammoth and ancestor to the modern boar. While 110 kilometers north of Bethlehem and 700,000 years later, Baboons lived south of the Lake of Tiberias, around Ubeidiya. Lakes were magnets for faunal activity and therefore hominin activity.

The An Nedfud desert of northern Saudi Arabia is classic wilderness today, 2 million years ago it was the hub of a diverse ecosystem with a lake as the centrepiece. The faunal remains were recovered from three localities and share similarities with the kind of fauna you would expect at Ubeidiya and the Oldupai Gorge. Hippos were found at these sites and since modern day counterparts prefer standing water to a depth of 5 meters, it gives an initial sense of the size of ‘Lake An Nedfud’. A lake capable of supporting fish life, but this is not the only lake to have supported faunal biodiversity in the ‘Black Hole’. ‘Lake Negev’ developed around 1.8 and disappeared around 1.5 million years ago under ever increasingly arid conditions. It supported fish populations and laid down 15 m thick sediments over 18 sq km². Besides these lakes, there were smaller lakes, Oases and springs that would have allowed hominins to hop, skip and jump out of Isis territory and into the more accommodating environments of Europe and eastern Asia. Looking at the faunal remains you can get a sense of the climate that prevailed at whatever time period you are interested in. The climatic mapping of the Pliocene and Early Pleistocene of the ‘Black Hole’ are, you’ve guessed it understudied. We do know that two and a half million years ago, the forests of Azerbaijan gave way to Savannah and the Arabian peninsula experienced 2 million years of humid conditions, capable of keeping many large (now extinct) rivers topped up.

Distribution of Landscapes (Dowsett et al. 1994, Figure 11)
Distribution of Landscapes (Dowsett et al – 1994 – Joint investigations of the Middle Pliocene climate I: PRISM paleoenvironmental reconstructions)

There you have it. We know alot, but we know so very little about this massive region of the world. We lack fossil hominins in this region and I don’t think Isis would be willing in finding their early ape ancestry any time soon. It would definitely be a useful distraction from Wahhabism. Do something useful for a change, Isis! Get out there and find us those damn fossils! You ignorant misogynistic apes!

Homo floresiensis: extracting ancient DNA: It’s been 8 years, any success?

Archaeogenetics, Archaeology, Archeogenetics, Archeology, Genetics, Palaeoanthropology, Paleoanthropology

I recently came across this scientific article in the Journal of Human Evolution entitled, Ancient DNA Analysis of Dental Calculus by Weyrich et al. It reminded me of the research conducted on the Indonesian hominin, Homo floresiensis. So, here I summarise what we know thus far. Dating to between 95,000 and 17,000 years ago, the hominin was found in the cave of Liang Bua, overlooking the Wae Racang river valley, on the island of Flores. It’s most remarkable feature was the 1.06 m stature of the individual found. Begging the question, how is this hominin related to us and what led to its diminutive stature. Much of the debate was thoroughly summarised in Leslie Aiello’s paper entitled, Five Years of Homo floresiensis, back in 2010. In short, some questioned the validity of naming these individuals a new species of human. Evidence was brought forward to support the hypothesis that these people were suffering from the neurodevelopmental disorder, Microcephaly and other diseases that induce a reduced stature. As time has passed, media sensation abated and researchers had a chance to step back, the majority are now more accepting of the Australian-Indonesian team’s decision to apply the new hominin nomenclature. Much of the debate hinges on skeletal comparisons between Homo floresiensis and other hominins, like us. There is one piece of information that the individuals of Liang Bua have yet to reveal – Deoxyribonucleic Acid.

Kilimutu Crater Lakes, Flores, Indonesia
Kilimutu Crater Lakes, Flores, Indonesia

Two teams of scientists, the Australian Centre for Ancient DNA (ACAD) and the Department of Evolutionary Anthropology at the Max Planck Institute (MPI) attempted and failed to extract DNA from the individual’s teeth in 2006. This was due to the environment in which the hominins were found, which was not conducive to DNA preservation. Christina Adler of ACAD hypothesised that the reason for extraction failure could be due to extraction procedure. In 2007 the ACAD team sucessfully extracted DNA from a pig tooth unearthed at the Liang Bua Cave, which was about 6,000 years old. The team suggested that first, Cementum (calcified root covering) is the richest source of DNA and second, drilling the specimen destroys the very molecule they are after. Armed with this knowledge another attempt to extract DNA from the hominins of Liang Bua is still yet to be carried out. The year 2013, saw the successful extraction of 400,000 year old DNA in Spain, so Floresiensian DNA may still lie within the teeth. I’m hoping, despite the less than ideal high temperatures of the cave sediments, there lies within those hominin individuals such strands of the good stuff.

Cranium and mandible cast of Homo floresiensis individual, LB1
Cranium and mandible cast of Homo floresiensis individual, LB1

Returning to the paper I mentioned at the beginning, it is a summary of all we know regarding the extraction of aDNA and steps to take when extracting it from calculus on teeth. Calculus is a hardened group of micro-organisms that appear as a yellow build-up usually around the gum-tooth boundary. The first demonstration of aDNA in Calculus was documented in a paper entitled Ancient Bacterial DNA (aDNA) in dental calculus from archaeological human remains by Preus et al., in 2011. A year later, aDNA was extracted from Neolithic Argentinian and Chilean humans. In that study, five bacterial species gene sequences were amplified by targeted polymerase chain reactions (PCR). By 2014, Warinner et al., used the power of the metagenomic sequencing strategy demonstrated increased resolution, the identification of antibiotic resistence genes and though the specimens were put through an Ethylenediaminetetraacetic acid (EDTA) and bleach treatments, DNA was recoverable.

Deoxyribonucleic Acid (DNA)
Deoxyribonucleic Acid (DNA)

When analysing hominin diets, microfossils are a large component, but the strides being made in aDNA extraction will mean that the species of plant or animal will be identified or as it usually does, throws up more questions than answers.

17 Palaeoanthropological Terms in Irish

Archaeology, Archeology, Evolution, Human Origins, Palaeoanthropology, Palaeontology, Paleoanthropology, Paleontology
Model: Shep – The Border Collie (12 years old)
Location: Carrowkeel, Co. Sligo
Taken: 26th of May 2018

Here are just some of the words, that you are likely to use in discussion of human evolutionary research. For more information regarding how to pronounce the words check out the video below.

Gaeilge To English

Pailéantraipeolaíocht – Palaeoanthropology

Anailís Lithic – Lithic Analysis

Seandálaíocht – Archaeology

Astrálaipiticín – Australopithecine

Scaipeadh – Dispersal

Bhreismheascadh – Admixture

Antrapóideach – Anthropoid

Pléisticéineach – Pleistocene

Geomoirfeolaíocht – Geomorphology

Bunús Daonna – Human Origins

Daoine anatamaíoch Nua-aimseartha – Anatomically Modern
Human

Ilchríoch – Continent

An Afraic – Africa

An Eoráise – Eurasia

Anailís Timpeallachta – Environmental Analysis

Dátú Argón-Argón – Argon/Argon Dating

Anailís Ghéiniteach – Genetic Analysis


17 Palaeoanthropological Terms in Irish / 17 Téarmaí Pailéantraipeolaíochta as Gaeilge

Cancer: The Earliest Carcinoma Yet Discovered

Archaeology, Archeology, Cancer, Human Evolution, Palaeoanthropology, Palaeopathology, Paleoanthropology, Paleopathology

You are looking at the rise of metastatic carcinoma in human body cells. A form of cancer with the ability to infect other organs in a biological organism. While Leprosy is the oldest documented disease in the world, thus far, dating to 4000 B.C. India. Ignoring the debate regarding the true age of knowledge in the Edwin Smith Papyrus (While it dates to 1600 B.C, the knowledge it contains may be as much as 1400 years older), evidence for Cancer may date back to northern Sudan 3,200 years ago.

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 Skeleton 244-8 was recovered from tomb G244 in the Amara West C cemetery in 2013. This 25 to 35 year old man was found with a considerable coverage of pin-sized perforations from shoulder to proximal femor. The bone tissue was therefore attacked by something. Historically Metastatic organ cancers are the most likely candidate as they prefer bone tissue. Tumor cells spread through haematopoietic-rich bone marrow creating holes as a result of bone reabsorption in a process known as osteolysis.

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 This research is helping us better understand the evolution of cancer and is a useful glance-back to remind us that animals and plants are not the only organisms that evolve, disease causing bacteria have evolved with us (animals, plants etc.) for hundreds of millions of years.

What about insects in hominin diets?

Archaeology, Archeology, Diet, DNA, Human Evolution, Insects, Journal of Human Evolution, Lithics, Palaeoanthropology, Paleoanthropology, Research
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For those fans of human evolutionary research news, you will be well aware of the lack of research into the role insects played in the diet of hominins over the past 6 or so million years.

This topic was addressed back in 2001 in the chapter of an academic volume by William McGrew of the department of Archaeology and Anthropology, University of Cambridge. Since then nothing has been done to address ways in which such an investigation could be conducted. What can be done to address this? Look at what we………..modern primate diets and the role insects play in their diets from the human to the Orang-utan. Let’s then look at the earliest evidence for hominin consumption of insects. South Africa has nabbed that prize, thus far. The Lower Palaeolithic sites of Swartkrans, Sterkfontein and Drimolen contained hominin fossil bone tools with wear patterns similar to those wear patterns you find on sticks used by Chimps to fish for termites. Fossil remains of Paranthropus robustus were found at these sites and the evidence suggests they were feasting on termites.

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Paranthropus boisei (Extinct cousin of Paranthropus robustus)

Examining the fossil evidence is one focus, but there are others including, lithics, residues, dental microwear, stable isotopes, DNA and coprolites (Fossilised shit…..basically). The dental microwear is quite problematic, because you have to take note that the tooth has been in the earth for millions of years (2.4 million years for the earliest Paranthropus specimen). Stable isotopic research is the much more promising of the topics discussed in William McGrew’s latest paper for the Journal of Human Evolution.