Sankar Chatterjee: From Dino-Man To Evolutionary Theorist


Dr. Subhamay Dutta: Bioinspiration and biomimetics have led to a variety of robotic designs in the history of robotic engineering. Tapejarawellnhoferi, a pterodactyloid of pterosaur from the Early Cretacious Period of Brazil provides critical information about the aerodynamic function of its cranial crest.’

Sankar Chatterjee is the Paul Whitfield Horn Professor of Geosciences and the curator of paleontology at Texas Tech University. He is a promising scientist from India who has led expeditions to India, China, Antarctica, and the American Southwest in search of dinosaur and early bird remains. His life according to me has two phases. In the first phase for about 40 years, he has worked on different types of flesh-eating and grass-eating dinosaurs and on the flight dynamics of pterosaurs. (Pterosaurs were avid flyers with highly developed wings. But they were reptiles and not dinosaurs which lived on this planet in the Early Mesozoic Age [266 – 65 MYA]). The second phase of his scientific life began about 10 years ago when he was dealing with the “Origin of Life” Theory the oldest scientific riddle posed by Darwin and Neo Darwinist like Alexander Oparin and JBS Haldane. So it’s an amazing story of the life of a scientist who turned into an evolutionary bioscientist from a dinosaur man.

First Phase

Before beginning with the first phase of Dr. Chatterjee’s life, I would like to brief some basics of dinosaurs.

 

The above tree is the simplified classification of the dinosaur family. Sauraschia is the reptile-hipped or lizard-hipped branch of dinosaurs. They are further classified into two subdivisions

  • Theropoda: Theropoda is a diverse group of bipedal dinosaurs from which modern birds came.
  • Sauropodamorpha: Sauropodamorpha were the long-necked, long-tailed vegetarian dinosaurs that we all saw in the movie Jurassic Park. They were harmless. Example: Brachiosaurus. On the other hand, Ornithischia was an extinct clade of mainly herbivorous dinosaurs characterized by a pelvic structure similar to that of birds, though they are not the ancestors of birds. Dr. Chatterjee has mainly focused on the origin, evolution of the anatomy of Mesozoic vertebrates in his first phase of the scientific career.

Among the Mesozoic Vertebrates, he worked on basal archosaurs (Extinct crocodilian relatives), dinosaurs, pterosaurs, and birds. He mainly focussed on the origin of flying birds as birds are the living dinosaurs. In his book “ The Rise of Birds -225 Million Years of Evolution” he has given a detailed explanation of his works and also the pioneering works of greats like John Ostrom, Robert T Bakker and to name a few. This puzzle of the missing link between birds and reptiles was first posed when a feathered Theropoda by the name Archeopteryxlithographica” was found in the limestone deposits of Solnhofen Germany. It was unearthed in 1860 and described in 1861 by Hermann von Meyer. Thomas Henry Huxley, the champion biologist and often known as “Darwin’s bulldog” worked on it and classified it as the ancient bird in the 1860’s. After that, a lot of great paleontologists tried to work on it. Othniel Charles March and Edward Drinker Cope also fought a lot on this puzzle but were unable to find a new path. The early 1990s discovery of Jeholbiota in Liaoning Province of northeast China and Daohugou biota completely changed the scenario of this old scientific puzzle of the missing link. Now Jeholornis is considered as the ancient bird. The detailed story of 225 millions of evolution is well presented by Dr. Chatterjee in his book” The Rise of Birds”. In the book, there is a chapter on Protoavis which Dr. Chatterjee discovered in the 1980s from the Late. Triassic Cooper Canyon Formation of West Texas. Protoavis is a controversial specimen. It lived around 210 million years ago. Its skeletal structure is far more advanced than that of Archeopteryx. But as the postcranial remains of Protoavis are badly preserved it was difficult for anatomical reconstruction. But certain features of its skeletal remains gave a hint that if it could be described as a primitive bird, it would push back the avian origins some 60-75 million years back. From 1975 to 2011, Dr. Chatterjee named 11 genera of dinosaurs :

Year Name of Genus (place of discovery)
1975 Barapasaurus (Pochampally, Telengana)
1985 Postosuchus (Post, Texas, US)
1987 Tikisuchus (Shahdol district of central India)
1991 Protavis (Post, Texas, US)
1993 Shuvosaurus (named after his younger sonShuvo [Western texas, US])
1994 Alwalkeria (Southern India) [ named after British palaeontologist Alick Walker ]
1995 Technosauras (Bull Canyon Formation of Texas, US)
2007 Lamplughsaura (Dharmaram formation of India)
2007 Pradhania (Dharmaram formation of India)
2011 Jaklapallisauras (Andhra Pradesh, India)
2011 Nambalia (Andhra Pradesh, India)

 

Bioinspiration and biomimetics have led to a variety of robotic designs in the history of robotic engineering. Tapejarawellnhoferi, a pterodactyloid of pterosaur from the Early Cretacious Period of Brazil provides critical information about the aerodynamic function of its cranial crest (cranial crest in the big flat structure over its head). In 2008, Dr. Chatterjee with Rick Lind of Aerospace Engineering Unit of the University of Florida developed an Unmanned Aerial Vehicle (Pterodrone) inspired by the flight dynamics of Tapejarawellnhoferi. The “Shiva Crater” is a geologic structure hypothesized by Dr. Sankar Chatterjee while studying the structure of Bombay High and Surat Depression. He proposed that the Shiva Crater was formed about 65 million years ago due to the bombardment of a meteorite during the fifth mass extinction: Cretaceous – Paleogene mass extinction event like the Chixulub Crater of Mexico. This is a briefing on the first phase of his scientific life.

Second Phase

“Origin of Life” theory is the oldest scientific puzzle that baffled the mind of many great scientists. Charles Darwin was the Father of Evolutionary Biology but he never directly posed the question of the first life on earth. In 1871, he told his botanist friend Joseph Dalton Hooker that if there was a pond where there were all the crucibles for life. Then with the help of some electric discharge or heat, it can participate in a chemical reaction to form a more complicated structure. Darwin was close enough to theorize it but he didn’t go beyond this. After 70 years two scientists from different parts of the world speculated a theory on the Origin of life. They were Alexander I Oparin from Russia and J.B.S Haldane from England. They both thought life to be formed from Methane, Water vapor, Hydrogen gas, and Ammonia with the support of a series of lightning and U.V. rays. These individual components of life got energized by lightning and rain from the atmosphere and created the organic soup known as “primordial soup.” But they didn’t consider the presence of oxygen at that ancient time as oxygen gas was first released by the photosynthetic bacteria during the process of photosynthesis. Their speculations were more or less the same but they had different conclusions. Haldane thought the prebiotic soup to be the prerequisite for nucleic acid formation while Oparin thought it to be the pre-requisite for protein formation. Chemist Stanley Miller and physicist Harold Urey did a famous experiment in 1950 to test this theory. They mixed the ingredients thought to be present on primitive earth and supplied electric spark to signify lightning. The results were amino acids. They got 20 amino acids as a result of this experiment but were unable to solve the combination pattern of these 20 amino acids to form a protein. Between the 1950’s and 1980s lot of scientists over the globe tried to create life but were unable to do that. In the late 1990s, David Deamer came up with a different theory of membraneous boundary structure that defines life today based on the analysis of Murchison meteorite that falls near Murchison, Victoria in Australia in 1969. Thus there were three scenarios present :

Protein first → Metabolism World (A.I. Oparin)

Gene first → RNA World (JBS Haldane)

Membrane first → Sequestered World (David Deamer)

Dr. Chatterjee in his symbiotic theory of the origin of life tried to hypothesize the different stages of development of life-based on the symbiogenesis theory of Lynn Margulis (evolutionary theorist and biologist) and Konstantin Merishkowich (botanist). Dr. Chatterjee’s hypothesis also took into account the results of the Stardust Mission of NASA. He proposed life to be formed in 4 stages as given in the picture below.

 

He is trying to decipher the origin of life from a geologic perspective. In recent times he has combined biology with information technology to decipher the origin of prebiotic information mystery to get the detailings of symbiogenesis. He along with Dr. Surya Yadav (Professor of Information System; Texas Tech University) has developed a software called CATI (Codon – Amino Acid – Translator – Imitator) to get a glimpse of Universal Genetic code responsible for all the evolutions of life forms.

This is the story of the transformation of a dinosaur man to an evolutionary theorist. Dr. Chatterjee in his 50 years of research life has 101 research items to his credit. He is the fellow of the Geological Society of America, Society of Vertebrate Paleontology, American Association for the Advancement of Science.

AWARDS & HONORS

Antarctic Service Medal, US: 1982

Headliner Award: 1992

  1. Rama Rao Birth Centenary Award; GSI, 2006.

BOOK

The Rise of Birds: 225 Million Years of Evolution: Johns Hopking University Press, 1997.

“JaistherHoludDufur” – Ananda Publishers.

“PrithibirSeshPrante” – Ananda Publishers.

He has been active contributors to journals including Science, Nature, Philosophical Transactions of Royal Society, Journal of Vertebrate Paleontology, etc.

Words: Dr. Subhamay Dutta

Photos: Wikimedia, Dr. Subhamay Dutta


About the author: Dr. Subhamay Dutta, Research Scholar of Applied Mathematics (Nonlinear Dynamics and Fluid Kinematics) and ardent nature lover. Hobby: Listening to music ( Eastern and Western Classical), Birder, loves to read any subjective text.

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