Posted on Leave a comment

Prehistory of Sri Lanka 7 : the Pleistocene flora and fauna of Ratnapura

Chandima Bandara Ambanwala

Department of Archaeology & Heritage Management, Rajarata University of  Sri Lanka, Mihintale.

Translated by. Chryshane Mendis

Chandima Ambanwala

The Pleistocene epoch is a scientific time period in geology which formed millions of years ago. During much of this epoch the world was covered under ice. This Pleistocene epoch had its effects on Sri Lanka as well according to geologists; Dr. Paul Edward Pieris Deraniyagala had conducted the most number of researches into this period in Sri Lanka. The details and results of his investigations into this epoch were included in a thesis which won him his Doctorate from Harvard University in the US. Based on that important thesis his book The Pleistocene of Ceylon was published by the Department of National Museums in 1958 (P.E.P. Deraniyagala (1958), The Pleistocene of Ceylon, Natural History Series, Ceylon National Museum, Ceylon). According to him this epoch would have been from 1.8 million years to 12,000-10,000 years ago.  All due credit for the present knowledge on the Pleistocene epoch amoung the scholarly society in Sri Lanka belong to Dr. P. E. P. Deraniyagala (He is the son of famous historian and Civil Servant Paul. E. Pieris and his son is the notable prehistorian and former Director General of the Archaeology Department Dr. Siran Upendra Deraniyagala). Before and after him, no Sri Lankan could be found with the interest to explore this important aspect of prehistory which is a sad situation. But the effort by Kalum Nalinda Manamendra-archchi out of the modern scholars to the study of fossils from the Rathnapura area must be appreciated. The difficulties in finding evidences, the lack of faith in the evidences revealed, inability to properly date the evidences, and the difficulty in identifying the context in which the finds are found can be stated as some of the factors that discourage scholars in the study of this period.

Dr. P.E.P. Deraniyagala

At 65,610 km2 Sri Lanka is one of the large islands in the Indian Ocean and during the Pleistocene epoch studies have shown that the island was joined to the mainland of the Indian Subcontinent. Due to the cold temperatures of this epoch the scattered glaciers caused the water level to fall and thus much of the places under water today was land during this time. Due to the drop in sea levels Sri Lanka and India was combined for the last time about 7,000 years ago. During the last 500,000 years the island was joined with the Indian mainland several times. According to some scientists during the past 1 million years the two lands were one landmass for most of the time. When the sea level fell approximately 70 meters, Sri Lanka and India was connected by a land bridge of about 100 km in width. Thus this land bridge caused species to inter-migrate between the two lands.

Kelum Nalinda Manamendra-archchi

At the end of the Pleistocene in Sri Lanka as a result of the rising temperatures the ice sheets that covered the world began to melt away. With the melting of the ice sheets the different materials found on the surface of the earth were mixed with the water and were deposited in low areas. Thus along with the alluvial deposits formed, environmental material on the surface through

The Pleistocene of Ceylon

anticline formations have been deposited in these low depths. Thus human and animal remains on the surface had been washed down and embedded in these deposits. The gem and seam deposits and other deposits of Rathnapura and other adjoining areas were created through the above process.

Found below is a comparison of this state of the Pleistocene with that found in the Alps mountain range by Dr. P. E. P. Deraniyagala. These ideas have been expressed by Dr. Deraniyagala with regard to the glacial periods of Gunz, Mindel, Riss and Wurm and also the warmer interglacial periods.

The soil layers of the gem and seam deposits of Rathnapura and the surrounding areas are the results of the melting of the ice from the mountainous areas. The fossilized remains of fauna and flora of that time or even before are preserved within these layers. In the process of excavating these seam deposits for gem stones, fossils of plant and animal life are usually found. Some of the main places that produce fossils in the Rathnapura alluvial deposits are Gatahaththa, Balangoda, Ambilipitiya and Kalawana. The gravel layer with such data is usually between 6 inches to 3 feet in depth and rarely exceeds 3 feet. The alluvial deposits can be found 12-40 feet deep and at certain places like Rakwana it is found 108 feet below the surface but certain places may also contain these deposits on the surface as well. Based on the data collected thus far, the details of the soil layers of a normal Rathnapura alluvial deposit can be stated as below.

            1 ½ feet – humus

            3 feet – loam

            5 feet – black clay

            5 feet – greyish clay

            3 feet – clay with fossils

            1 ½ feet – sand

            1 ½ feet – gravel

            ½ feet – mineral gravels with large amounts of fossils

            Bedrock

It is evident that certain layers containing fossils have been re-deposited due to the process of glacierization. According to the above it is hard to ascertain that these would have been deposited in a regular/methodical way as certain deposits have been found which were thought to be very old but contained pearls, pottery and iron of much later periods. Such deposits show a disturbed nature therefore because of this it is difficult to properly date the deposits chronologically.

A gem mine in Rathnapura (image taken from www.mysrilankaholidays.com)

In the middle of the 1930s under the supervision of P. E. P. Deraniyagala from the National Museums (in 1939 he was made Director of National Museums), investigations were carried out into the alluvial strata that contained gem stones in the Rathnapura deposits. From then until 1963 the fossils of animal and plant life were subjected to investigation by Dr. Deraniyagala. By examining the fossil records found within these layers, a high knowledge on the species that lived during the Pleistocene was developed and amoung them identifying animal species that have gone extinct and those that are still living.

Below is a list of the large number of spices that have gone extinct.

Scientific name Common name Features
1 Geoemyda trijuga sinhaleya A species of tortoise Can be larger than the present ඝණ කටු සහිත ඉබ්බා tortoise
2 Trionyx punctate sinhaleya A species of tortoise  Can be larger than the present මෘ දු කටුව සහිත ඉබ්බා
3 Crocodylus sp. A species of Crocodile A more slender head than the present crocodile
4 Hypselephus hysundricus sinhaleyus A species of Elephant Comparable to the Indian sub-species.
5 Palaeoloxodon namadicus sinhaleyus A species of Elephant Could be a smaller species than the Indian sub-species.
6 Rhinocerus sinhaleyus A species of Rhinoceros A single horned Rhinoceros
7 Rhinocerus kagavena A species of Rhinoceros A single horned Rhinoceros
8 Hexaprotodon sinhaleyus A species of Hippopotamus A Hippopotamus very similar to Hexaprotodon palaeindicus of the Narmada region but with 6 teeth in the front.
9 Hystrix sivalensis sinhaleyus A species of Porcupine Relatively small in size.
10 Homopithecus sinhaleyus A hominid species From a gem mine in the Karangoda area of Ratnapura.
11 Homo sinhaleyus A hominid species From a area close to Ratnapura.
12 Elephas maximus sinhaleyus A species of Elephant Now extinct.
13 Leo leo sinhaleyus A species of Lion A lion much larger than the present Indian lion.
14 Muva sinhaleya A species of Sambur Small in size.
15 Sus sinhaleyus A species of Wild boar 2/3 the size of the present Wild boar in Sri Lanka.
16 Bibos gaurus sinhaleyus A species of Bison Shorter small horns than the present Indian bison.
17 Gona sinhaleya කුළුමීමා Could be the ancestor of the කුළුමීමා Bos indicus that inhabits the North Central Province.
18 Tatera sinhaleya A species of Rat This species had longer and broader teeth than the present Rat in Sri Lanka.
19 Axis axis ceylonensis Spotted deer The present spotted deer.
20 Rusa unicolor Sambar deer The present Sambar.
21 Bubalus bubalis migona Buffalo The present Buffalo.

Number 10 & 11 in the above, Homopithecus sinhaleyus and Homo sinhaleyus respectively are two of the most important fossil finds. An ancestor of modern humans, the fossil of Homopithecus sinhaleyus which was an incisor tooth was found from a gem mine in the Karangoda area of Ratnapura.

The tooth belonging to Homopithecus sinhaleyus and the skull fragment above the left eye of Homo sinhaleyus. (Images by Kalum Nalinda Manadendarachchi )

The enamel of the tooth has turned black and is semi-cylindrical at the bottom which enlarges when going up. The deposit stratification of the site that contained this fossil is given below:

6 feet – black mud

 6 feet – laterite soil

3 feet – organic materials and sand

 1 ½  feet – blue clay

1 feet – fine white sand

 ½ feet – hardened sand

1 feet – Gem gravel with fossils (the layer in which these fossils were found)

Decayed rock

Bedrock

The fossil of the hominid Homopithecus sinhaleyus was found along with the fossils of Hexaprotodon sinhaleyus, Rhinoceros kagavena, Elephas maximus sinhaleyus, Axis axis ceylonensis, and Rusa unicolor unicolor and through the Uranium dating method were dated to the same period.

Below is a result of the comparison of the incisor tooth of Homopithecus sinhaleyus with the same of a modern Gorilla and Human.

The extinct Hypeselephas hysundricus

Through this comparison it is proven that this belonged to an ancestor of modern humans and also it shows close resemblance to those of Pithecanthropus robustus of Java and Gigantopithecus blacki of China. Further Prof. A. Raymond of the University of Kyle? Through his great knowledge on the subject has stated this to be a fossil of an ancestor of humans.

The fossil of Homo sinhaleyus was found in a location close to Ratnapura and make up the bone fragment of the skull above the left eye. Along with this, the fossils of Hexaprotodon and Elephas maximus sinhaleyus and the deposit stratification of the site that contained these fossils are given below:

            3 feet – humus

            2 ½  feet – laterite soil

            4 feet – blue clay

            1 ½  feet – organic material and mud layer

            2 feet – black sand

            ½ – 2 feet – Gem gravel with fossils (the layer in which these fossils were found)

            Bedrock

When taking the measurements of this bone fragment, the eye cavity was found to be relatively small, thus based on these measurements Dr. Deraniyagala has stated that this could be compared to the Neanderthal humans.

The relative age of the fossils of the Ratnapura deposits can be determined through comparison. Therefore the assumptions can be arranged as below:

  1. Hexaprotodon is older than Elephas maximus sinhaleyus.
  2. Hexaprotodon can sometimes be even older than Rhinoceros kagavena.
  3. Hexaprotodon, Elephas maximus sinhaleyus, Rhinoceros kagavena are same period/contemporary. There is a high possibility that the incisor tooth of Homopithecus sinhaleyus is of the same period as them.
  4. Rhinoceros kagavena can be twice as old as Elephas maximus sinhaleyus and also a bit older than

There are also plant fossils found from these deposits and according to the radiocarbon dating done by the TATA Corporation of India, the below results were arrived at:

  • Mesua species more than 47,000 years BP (Before the Present)
  • Largestroemia speciosa 7520 +/- 150 BP

These plants can even be found at present in this region.

The now extinct Rhinocerus sinhaleyus that lived during the Ice Age (Pic.by. K.N. Manamendra-archchi)

The fossils found from the gem mines of Ratnapura share a comparison with those found in the regions of Swahilik and Narmada basins of India as shown by Dr. Deraniyagala. These regions of India belong to the Middle Pleistocene epoch.

Through this we could get a sound knowledge on this historical time period which is the Pleistocene. But as shown above due to the re-depositing, it is an obstruction to dating these finds accurately. But with modern technological developments it is important to re-examine these fossils; this could be done through the collaboration of future archaeologists, archaezoologists and geologists which could yield more important evidences.

Posted on Leave a comment

Excavating Alugalge: archaeology.lk visits the excavations of the prehistoric site

By Chryshane Mendis

Chryshane Mendis

Excavation of the prehistoric cave of Alugalge is conducted by the Field Archaeology Unit of the Postgraduate Institute of Archaeology (PGIAR) led by Professor Raj Somadeva and a team of Researchers from the PGIAR and University students. The excavation which is funded by the PGIAR and the National Science Foundation (NSF) is part of the field work of the ‘Hunters in Transition’ project which aims at identifying the pre and proto historic transition which would have occurred in the mid or late Holocene Epoch. This project is the extension of the research programme of ‘Archaeology of the UdaWalave Basin’ begun in 2006 the area of which had been identified as an environmentally optimal area to study this transition. This 15 year project is currently running in its 9th season with the present excavation. The Archaeology.lk team visited the excavations in mid-March to gain an insight on this current excavation and as to what goes on during an archaeological dig.

Alugalge is located in the village of Illukumbura in Balangoda of the Rathnapura District. To reach here one must travel to Balangoda and upon reaching Kirimatithenna junction which is 3.5km passing Balangoda town on the Kaltota road, turn right on the Weligepola road and proceed about 10km to Kongasthenna junction. From here take the Illukkumbura road to the right and proceed about 5km passing the scenic Panana village to a sharp 90 degree turn to the left, from where one must take the small road to the right and travel about 2km through the hilly tea estates and home gardens to the Illukkumbura school and from here it is a 1km downhill hike from the road onto the left. The team of Archaeologists and Prof. Somadeva are based in a rented house in the beautiful peaceful village of Illukkumbura which is about 3km from the site.

[wpgmza id=”1″]

Alugalge Cave on Google Map

Summary of the excavations 

Speaking to the Professor and the team, they explained that this is the second phase of the excavation of the Alugalge cave which commenced on the 20th February 2017 and is planned for a period of 6 weeks but that the duration could be extended or shortened based on the excavations.  This cave was for the first time surveyed and excavated in August 2016 which yielded evidence of prehistoric habitation and put the occupation of the site in about 3,450 B.C. with the most interesting find being that of a Shark tooth pendant.

Inquiring into the identification of this site, they explained that after every excavation an exhibition and awareness programme is conducted in the villages from which the residents share their knowledge of possible locations which are afterwards surveyed. The cave of Alugalge was one of the many such locations identified by the people and after conducting several surveys of other nearby caves, this particular cave was selected. Such programmes with the village folk have proved very valuable and their interest in identifying and reporting on possible locations is quite noteworthy and the help and support given to the excavation by people is remarkable as the writer witnessed.

Explaining on how they conducted the excavations; about a week was spent on surveying the site and only after a thorough survey is it decided to excavate. The cave, which was excavated on the previous occasion, was excavated to a further depth this season. Once the surveying was completed they laid the gird plan and conducted the profile drawing of the levels which is of most importance and only then was it begun to excavate.

Excavation within the cave. (Photograph by Dinesh Devage)

 

Prof. Somadeva examining some finds (Photograph by Dinesh Devage)

The excavated soil layers go through two processes in order to obtain artefacts, first by dry sieving and second by wet sieving. The section of the excavated soil is marked by the grid number and layer number for a systematic identification and only then taken through the above two processes which are conducted at the site. This dry and wet sieving is a careful process and is done through experienced hands due to the delicate nature of the artefacts. Artefacts are selected during these two stages as well and further after the wet sieving; the soil is carefully dried and brought in marked bags back to the house for a more careful piece by piece identification and selection.

Photograph by Dinesh Devage

The recovered soils which are carefully marked are brought back to the house and some entire days are spent on selecting the artefacts from them. When the writer visited the excavations, both days spent there were on this separation of artefacts from the soil layers; which as the writer witnessed is equally exciting and fun as digging in the cave because for to the archaeologically eyed participant, every step of an excavation be it in the field or indoors is sensational as something new to knowledge is brought to light every moment.

Drying of the soil after wet sieving

 

Sorting out the artefacts at the house

Once dried, the soil is spread on a white polythene sheet on a table and using a variety of twisers one by one the tiny particles are separated into different containers.

It is amazing as to the amount of artifacts that turn up from just one bag of soil; for when spread out on the sheet, what seems like a heap of soil and dirt, when separated piece by piece reveals an array of artefacts. The artefacts found are Quartz stone tools and flakes, remains of animal bones and bone tools including teeth, shells, pieces of burnt clay, pieces of charcoal, and sometimes tiny pieces of graphite. The more remarkable findings are measured and cataloged separately for further analysis.

Before separation

Bone fragments
Burnt clay
Identified stone tools

Stone tools are usually made from Quartz and Chert, but from this site only Quartz tools were found and make up the largest percentage of artefacts found and these are classified as microliths due to many being less than a centimeter in size.

The artefacts sealed in separate bags.

Some of the shells discovered belong to the species Acavus haemastoma and seeds found here are identified as Dik Kekuna (Canerium zelanicum) which are still found in this area. These artifacts are then sealed in small transparent bags and labeled according to the grid and layer number from where they were excavated. These will be taken for further analysis.  The bags of soil recovered from the site amount to over a hundred and from morning till night are being painstakingly sorted out by the team. The patience that one requires to perform this is immense and it requires a trained eye to spot the artefacts from the soil and rocks.

When at the site the team would spend about 8 hours from 8 am in the morning till about 4 pm in the evening and when at the house as when the writer witnessed, from around 7 am they would sit on the benches sorting out the artefacts till 10 pm in the night only resting for meals and tea and the interesting stories of the Professor.

Traveling to the source of these wonderful finds, the Alugalge cave is located 3km from the house, the first two kilometers is motorable and turning off from the Illukkumbura school to the left we parked the motor cycle in a house nearby and began the 1km downhill hike to the cave. The first 500m is through the backyards of few houses and then takes a rather steep decent through patches of forests and small tea estates. The path is very narrow and there are many other footpaths joining the main path which makes it tricky but is now quite familiar to the team now used to trekking this path daily for almost a month. Traveling through the beautiful woods to a very low elevation the path turned north along a small ridge and came up beside a massive rock several dozen feet high, here lay the shelter of the prehistoric man, the Alugalge cave. The area has been arranged well for the dig, with a hose and tap brought from a nearby estate and much equipment such as spades and shovels including a generator used to light up the inside of the cave. The mouth of the cave opens up to the west and is surrounded by thick evergreen forests. When excavating, the team hikes down here daily, leaving the house at 7 am in the morning and arriving near the Illukkumbura School in a hired truck and making the downwards decent to the site carrying all the equipment and meals and work at the site till about 4 pm in the evening. The villagers are very supportive and have great respect to the Professor and team as the writer witnessed and many children from the village come to observe the excavations. For the lover of nature and history, this is the ultimate satisfaction.

On the way to the site
Some of the scenic houses on the way to the cave.
Entering the cave from the path.
Lighting the inside of the cave.

The team with Prof. Somadeva (Photograph by Dinesh Devage)

The excavations are scheduled to conclude end of March and only a scientific analysis of the findings back at the PGIAR would reveal the full worth of this season’s discoveries. The fascinating field of archaeology never fails to amuse the mind of even the most uninterested person with its wonderful stories of the past, spectacular findings, most of the time touched last by human hands over thousands of years ago and also the stories of the present, of the places visited, people encountered and the diversity of cultures witnessed. Although separated from family and friends for several weeks, the lover of archaeology is ever happy at heart for he who uncovers history finds happiness in diversity and wherever he or she may be, will always feel at home.

References

  • Somadeva, R. (2011), Archaeology of the Uda Walave Basin. Occasional Paper no. 2, Postgraduate Institute of Archaeology, Colombo: Postgraduate Institute of Archaeology.
  • Somadeva, R. (2014), Archaeology of Mountain, Occasional Paper no. 3, Postgraduate Institute of Archaeology, Colombo: Postgraduate Institute of Archaeology.