Thierry Smith is a research team leader at the Royal Belgian Institute of Natural Sciences in Brussels, Belgium. He was awarded a Leakey Foundation research grant during our fall 2016 cycle for his project entitled “Diversity and relationships of earliest Euprimates from Tadkeshwar Mine, India.”
Several open cast lignite mines of Gujarat, Western India, that expose the subsurface beds of the early Eocene Cambay Shale Formation (about 54.5 million years old) have yielded the oldest Cenozoic land mammals of India, including primates of modern aspects (euprimates). They are some of the most primitive euprimates in the world. These important discoveries on the Indian plate from the time it was drifting northward toward Asia have recently reopened the debate about the strepsirrhine-haplorhine divergence.
The primate fauna consists of at least two primitive adapoids (Marcgodinotius indicus and Asiadapis cambayensis) and two omomyids (Vastanomys gracilis and V. major), as well as a putative basal anthropoid (Anthrasimias gujaratensis). It appears likely that these are the sister taxa of all later primates, ultimately including humans. Skeletal elements referable to several of the Indian primates are the oldest well preserved euprimate postcrania known to date, and their primitive anatomy suggests that they are very close to the initial divergence between strepsirrhines and haplorhines.
The overall research objectives of our Indian-American-Belgian team are: 1. to study the diversity of early Eocene euprimates from Gujarat and to compare them to other early euprimates, including earliest anthropoids; and 2. to learn more about the role of India in the basal radiation of euprimates that led to our anthropoid ancestors.
It is essential to find more complete specimens in order to determine their significance. Therefore, our field team will explore and excavate the new Tadkeshwar Lignite Mine. We will prospect for continental lenses situated near the lignite beds and fluviatile channels situated between the lignite beds with the help of the mine personnel using heavy equipment to remove overburden to gain access to the fossiliferous deposits in Tadkeshwar Mine. Once matrix has been inspected for vertebrate fossils, it will be screen-washed to recover small bones, jaws, and teeth of primate fossils.