Bhopal: Scientists from Delhi University, during their fieldwork, have discovered double-layered in-situ egg in a titanosaurid sauropod nest in the Upper Cretaceous Lameta Formation of Padlya of Dhar District, Madhya Pradesh in central India.
This find represents the first discovery of ovum-in-ovo pathology in dinosaurs.
The discovery of double-layered in-situ egg is significant as it represents the first discovery of ovum-in-ovo pathology in dinosaurs. Harsha Dhiman, along with Vishal Verma and Guntupalli V.R. Prasad, have hypothesised in their research article published on 7 June 2022 by Nature, a weekly peer-reviewed international research journal that ovum-in-ovo pathology is not unique only to birds, and sauropod dinosaurs had a reproductive anatomy more similar to those of archosaurs such as crocodiles and birds, rather than to those of non-archosaurian reptiles like turtles and lizards.
The report by senior author Harsha Dhiman, et al, states “The in-situ pathological titanosaurid dinosaur egg was found in the sandy limestone/calcareous sandstone of the Upper Cretaceous Lameta Formation exposed in the lower Narmada valley. The Lameta Formation in the Narmada valley consists of arenaceous, argillaceous, and calcareous sediments deposited in continental palaeoenvironmental conditions in a semi-arid to arid palaeoclimatic setting. “
“It is widely distributed in the form of isolated and patchy outcrops in central (M.P., Maharashtra) and western India (M.P., Gujarat). The Lameta Formation is well known for its titanosaur nesting sites, isolated eggs and eggshell fragments. During multiple field-works conducted by the authors in the Bagh-Kukshi areas of Dhar District of M.P., 108 titanosaur nests were identified which include intact clutches, isolated eggs and several eggshell fragments.”
“The nest preserving the pathologic egg is documented from the village Padlya of Dhar District, M.P. (Fig. 2). Here the Lameta outcrops measure less than a meter to 4–5 m in thickness and exhibit dark-grey surface color.”
Fifty-two sauropod dinosaur nests have been documented from the village Padlya in the form of clutches consisting of two to twenty eggs, nests with single eggs, and outcrops with only eggshell fragments. The pathologic ovum-in-ovo egg has been documented from an outcrop (nest number P7) situated near the Padlya village, which has now been shifted to the premises of Dinosaur Fossil National Park (designated by M.P. state government), close to Padlya village to keep it safe from illegal fossil collectors.
The nest P7 preserves eleven eggs randomly placed with respect to each other in a circular nest arrangement as indicated by variable diameters of circular shaped eggs (Fig. 4). The eggs are present in the form of semi- to completely circular outlines (Figs. 5, 6), bottom surfaces of eggs encrusted with eggshells (Fig. 7), circular-shaped molds of eggs (Fig. 6a), and as eggshell fragments present inside and/or around the egg outlines (Fig. 6b). Some eggshell fragments also occur randomly (Fig. 8). The minimum and maximum egg diameters are 13 cm and 16.6 cm, respectively and the eggs are sub-circular to elliptical in shape, the latter of which is a compressed egg.
Madhya Pradesh has a number of fossil parks. These are Ghughwa, near Jabalpur. Here one can see millions of year old tree fossils.
Close to where the Delhi University researchers found the Dinosaur egg in situ is Dinosaur National Park in Bagh falling under the Dhar Forest Division. The park’s wild landscapes, topography, geology, paleontology, and history make it a unique resource for both science and recreation. This landscape was once part of Coast of Tethys Sea when India subcontinent was travelling towards Eurasian approx. 100 million years ago. Due to Deccan lava explosions and volcanic activities these estuarine ecosystem is beautifully preserved under constant flow of lava over it. Since whole estuarine landscape got fossilized diversity in fossils is huge and unparalleled which cannot be found in any other part of the world.
Fossils discovered from this area includes sauropod (herbivore dinosaur) bones, Complete nest of dinosaurs along with the eggs , shark teeth , footprint of dinosaur , tree Fossils ,marine mollusks such as oysters and gastropods, inoceramids and other marine organism fossils
About 12 years ago, a team of local archaeologists led by Rajiv Choubey, had found Dinosaur fossils with a wing-span of 30 feet near near the Siddhanath Ghat in Thala Dighavan village on the northern bank of Narmada river, not far from Udaipura town in Raisen district of Madhya Pradesh. The village has many fossilised remains of different species of dinosaurs.