An international team of researchers has unearthed a 13 million year old fossil of a newly discovered ape species in Jammu and Kashmir’s district Udhampur which is the earliest known ancestor of the modern day gibbon. It provides important new evidence about when the ancestors of today’s gibbon migrated to Asia from Africa. The fossil, a complete lower molar, belongs to a previously unknown genus and species ( Kapi ramnagarensis), and represents the first new fossil ape species discovered at the famous fossil site of Ramnagar in nearly a century.
Prof Rajeev Patnaik (Head of the Department, Dept, of Geology, Panjab University, Chandigarh) told the author that in 2010, an international team comprising of paleontologists and geologists from India and the United States led by him including Prof. Chris Gilbert (City University of New York),Dr Biren Patel(University of California) and Dr. Chris Campisano ( Arizona State University) initiated new paleontological and geological fieldwork in Ramnagar area of district Udhampur. Their research has since then been supported by various agencies like (Department of Science and Technology-PURSE grant to PU, Ministry of Earth Science of India to Rajeev Patnaik) and US based (Leakey Foundation) grants. They focused on studying South Asian mammalian (in particular, primate evolution and biogeography). Their team has documented a number of new fossiliferrous localities from which they have recovered new primate fossils representing a new Sivaldapid genus and species (Ramadapis sahnii; Gilbert et al., 2017) , a large bodied -ape attributed to Sivapithecus (Gilbert et al., 2019) and a new small- bodied ape ( Gilbert et al., 2020) (Figure 1).
According to Chris C Gilbert, “there are other primate species known during that time, and no gibbon fossils have previously been found anywhere near Ramnagar. Since the fossils were discovered in 2015; years of study, analysis and comparison were conducted to verify that the tooth belongs to a new species, as well as to accurately determine its place in the ape family tree”. It pushes back the oldest known fossil record of gibbons by at least 5 million years, providing a much- needed glimpse into the early stages of their evolutionary history. In addition to determining that the new ape represents the earliest known fossil gibbon, the age of the fossil around 13 million years old, is contemporaneous with well known great ape fossils, providing evidence that the migration of great ape, including orangutan ancestors, and lesser apes from Africa to Asia happened around the same time and through the same places.
There have been several reports of the discovery of fossils claimed to be of man’s ‘true ancestors’ from time to time. They include two, named Proconsul and Kenyapithecus, from Kenya; two, named Ramapithecus and Sivapithecus, from locations in India, Pakistan, China and Kenya; and two, named Dryopithecus and Rudapithecus, from Europe. These ape-like creatures lived at various time between about 8 and 20 million years ago. Of these the one that created a sensation and which was once regarded as man’s oldest direct ancestor was Ramapithecus, fossils of the upper jaw of which were first found in the Siwalik Hills in India.
But G. E. Lewis was the first to recognize the Siwalik hominid Ramapithecus from Haritalyangar, a village near Bilaspur, Himachal Pradesh. Later Elwyn Simons’ efforts in the late sixties and early seventies led to an upsurge in research around Haritalyangar, resulting in some outstanding discoveries of fossil primates. Recently, Haritalyangar has yielded additional new evidence of fossil apes, information about their habitat and the main cause of their extinction.
Fossil apes and other mammals have been known from Miocene -aged Lower Siwalik deposits surrounding the town of Ramnagar district Udhampur ( Jammu and Kashmir, India) since Barnum Brown’s American Museum of Natural History expedition in 1922.
Significantly, the first primate fossil discovery at Ramnagar was made by US born collector Barnum Brown in 1924 when he found an important fossil jaw of an early great ape (now known as Sivapithecus indicus), which is a close relative of the living orangutan. Paleontological fieldwork has continued on and off in the Ramnagar region since 1922, resulting in the recovery of a large number of vertebrate fossils, including small number of additional ape specimens attributed to the genus Sivapithecus and a single adapoid primate, Sivaladapis palaeindicus ( Pilgrim,1927; Gregory et al.,1938; Vasishat et al., 1978; Thomas and Verma, 1979; Gaur and Chopra,1983; Nanda and Sehgal,1993; Basu,2004; Kelley,2005; Sehgal and Patnaik,2012).
Over the past century, numerous specimens collected near Ramnagar (J&K) India have proven to be important in understanding the evolution and biography of many mammalian groups, including hominoid apes. Since 2010, they have received fossil prospecting in the lower Siwalik deposits near Ramnagar in an attempt to better understand the evolution, biogeography timing and paleoclimatic context of mammalian radiations in Asia, with a particular focus on primates.
It is believed that the age of the new sites and the Ramnagar region in general, can be bracketed by micro and macro-fauna to approximately 14-12.7 Ma which suggests the area may slightly be older than the classic ape-bearing Chinji deposits on the Pakistan Potwar Plateau. Thus, the Ramnagar region may represent the first occurrence of apes and other mammalian lineages in the Siwalik.
Future plans: According to Rajeev Patnaik that primates are rare elements of the fauna across known Siwalik localities, the recovery of these primate specimens by their team is promising; it shows that the Ramnagar region provides the rare opportunity to obtain additional rare specimens that can now be uncovered with additional fieldwork. Also they are now focusing on the diet and habitat of these primates and associated mammals to understand the influence of climate change on their evolution.