The Pondaung Formation is a geologic formation which consists of layers of red beds alternating with grey sandstones sediments, dated to about 40 million years ago. Several of these outcrops around Bahin village, located in the Dry Zone of central Myanmar, contain fossils of the oldest representatives of anthropoid primates, which correspond to the class that includes monkeys, apes and humans. Therefore, mankind’s earliest primate ancestors are documented from these Paleontological sites which are unique in Asia, and believed to be the oldest in the world. The significance of these sites lies in the fact that for many years it was generally considered by the scientific community that anthropoid primates originated in Africa. But more than thirty years of international research has suggested that the earliest anthropoids arose in South East Asia and subsequently dispersed to Africa at about 40 million years ago during the Middle Eocene. The fossil specimens from the Pondaung Formation contain the oldest knowns anthropoids yet discovered anywhere in the world. These fossil sites have delivered 6 distinct forms of these earliest anthropoids, distributed in two families, the Eosimiidae and the Amphipithecidae. Bahiniapondaungensis, a member of the family Eosimiidae, is the most primitive known anthropoid primate, universally considered as the ancestor of modern anthropoids.
These important fossils have been discovered in several outcrops clustered around Bahin Village, Myaing Township, Magway Region about 80 km from northwest of Bagan. Nearly 100 incomplete primate fossil specimens and thousands of associated mammal and other vertebrate fossils have been collected from these outcrops, and stored in the National Museum of Naypyitaw, in Yangon at the Department of Archaeology, and in the National Museums in Yangon and Mandalay. Although these fossil sites are officially-gazetted protected sites designated by the Department of Archaeology and National Museums, Ministry of Religious Affairs and Culture, and clearly identified as protected site by on-site notification boards, these outcrops are presently under huge pressure due to the intensive economic development of agriculture in the surrounding area, which has dramatically increased exposure, erosion, and weathering of the fossil deposits. Fossiliferous outcrops are trampled by goats and cattle, and are also progressively incorporated into cultivated fields by farmers unaware and ignorant of their scientific value.
Pondaung anthropoid primate sites represent the oldest anthropoid community identified so far from any region of the world. No other in-situ fossil sites have yielded such a diversified anthropoid fauna, at such an early date of 40 million years ago, making these sites unique in the world and of potential high outstanding universal value for their scientific study of anthropoid evolution. Natural erosion and scientific excavations reveal additional fossil anthropoid primates specimens every year, making the Pondaung Formation an exceptional area for the understanding of the earliest steps of anthropoid primate evolution, which led eventually to the evolution of hominids.
Criterion (viii): The Pondaung Formation and associated fossil beds represents a major stage of the Earth’s history wherein the earliest steps of evolution and adaptation of anthropoid primates is documented with in-situ deposits. The Pondaung Formation has not only yielded anthropoid primates fossil but complete ecological communities of contemporary flora and fauna documenting paleo-ecosystems of both fresh water and terrestrial domains 40 million years old. These ecological communities have been well studied and documented through more than 30 years of scientific investigation, which continues. Evidence for the evolutionary interactions between the changing paleo-climates and associated terrestrial mammal communities with the anthropoid primates are important for the study and understanding of how primate (including hominid) evolution may change under long-term climatic stress and temporal variation. As a unique fossiliferous formation, the outcrops of the Pondaung Formation are of potential outstanding universal value to be protected in order to allow ongoing and future scientific research.
In their present state, the nominated anthropoid primates palaeontological fossil sites in the Pondaung Formation are gazetted as protected areas for scientific research and are relatively well safeguarded. Human density in the area is low but is increasing regularly, at a manageable rate. Site boundary markers have been installed around the most important sites by the Ministry of Religious Affairs and Culture. These boundary marker stones delimit the important localities, and indicate to the local inhabitants that theses are areas of high cultural importance, but do not isolate these areas from human or livestock activity. The most specific and immediate threats to these fossil sites comes from the partial or total incorporation of some of the sites into cultivated areas, and in the possibility for some of them to be included in a small-scale irrigation projects and/or as possible sites for future drilling of oil wells.
The anthropoid primate fossil sites of the Pondaung Formation are unique in the world in terms of their (i) age; (ii) diversity of primate families and species represented, and (iii) in-situ association with other mammalian fossils of comparable age.
Messel Fossil Pit: The most similar site inscribed on the World Heritage List may be Messel Fossil Pit, in Germany. Messel Fossil Pit contains exceptionally diverse fossil Lager statten including aquatic and terrestrial fauna and flora of the Early Tertiary, and undoubtedly offers a unique window on the evolution and radiation of mammals. As such Messel Fossil Pit is an important site for the understanding of the evolution of Early Tertiary palaeo-environments.
The Pondaung anthropoid primates paleontological sites are not, however, precisely comparative to Messel Fossil Pit. Whereas Messel Fossil Pit contains fossil remains of a wide range of vertebrates covering the whole of the Eocene period, the Pondaung Formation dates specifically to the late Middle Eocene and contains notably the earliest knows in-situ remains of anthropoid primates(34 families, 69 species from 7 anthropoid primate genera) in association with fossil remains of many mammals and other vertebrate fauna. Therefore, the Pondaung anthropoid primates palaeontological sites stand out for their unique importance for the study and understanding of the earliest step of primate evolution within the context of the evolving paleo-environment.