A5069216734- Evolution and Paleontology Studies
- Paleontology and Evolutionary Biology
- Geology and Paleoclimatology Research
- Marine animal studies overview
- Bat Biology and Ecology Studies
- Ichthyology and Marine Biology
- Paleontology and Stratigraphy of Fossils
- Amphibian and Reptile Biology
- Geological and Geochemical Analysis
- Pleistocene-Era Hominins and Archaeology
- Animal Ecology and Behavior Studies
- Primate Behavior and Ecology
- Geological formations and processes
- Fish biology, ecology, and behavior
- Geological and Geophysical Studies
- Turtle Biology and Conservation
- Isotope Analysis in Ecology
- Fish Biology and Ecology Studies
- earthquake and tectonic studies
- Geochemistry and Geologic Mapping
- Plant Diversity and Evolution
- Maritime and Coastal Archaeology
- Cephalopods and Marine Biology
- Subterranean biodiversity and taxonomy
- Underwater Acoustics Research
Indian Institute of Technology Roorkee
2014-2024
Government of India
2022
Indian Institute of Management Lucknow
2018
Indian Institute of Technology Indore
2009-2014
Shell (India)
2013
GTx (United States)
2005
University of Michigan–Ann Arbor
1998
Panjab University
1988-1994
University of the Punjab
1989
Cetaceans (whales, dolphins, and porpoises) are an order of mammals that originated about 50 million years ago in the Eocene epoch. Even though all modern cetaceans obligate aquatic mammals, early were amphibious, their ancestors terrestrial artiodactyls, similar to small deer. The transition from land water is documented by a series intermediate fossils, many which known India Pakistan. We review raoellid as well earliest families cetaceans: pakicetids, ambulocetids, remingtonocetids,...
Among mammals, modern cetaceans (whales, dolphins, and porpoises) are unusual in the absence of hind limbs. However, cetacean embryos do initiate hind-limb bud development. In arrests degenerates around fifth gestational week. Initial limb outgrowth amniotes is maintained by two signaling centers, apical ectodermal ridge (AER) zone polarizing activity (ZPA). Our data indicate that forms an AER this structure expresses Fgf8 initially, but neither nor expression maintained. Moreover, Sonic...
Undisputed anthropoids appear in the fossil record of Africa and Asia by middle Eocene, about 45 Ma. Here, we report discovery an early Eocene eosimiid anthropoid primate from India, named Anthrasimias , that extends Asian 9–10 million years. A phylogenetic analysis 75 taxa 343 characters skull, postcranium, dentition living primates indicates basal placement among eosimiids, confirms status Eosimiidae, suggests crown haplorhines (tarsiers monkeys) are sister clade Omomyoidea not nested...
Research Article| January 01, 2011 Early Eocene warming events and the timing of terrestrial faunal exchange between India Asia Mark Clementz; Clementz * 1Department Geology Geophysics, University Wyoming, Laramie, Wyoming 82071, USA *E-mail: mclemen1@uwyo.edu. Search for other works by this author on: GSW Google Scholar S. Bajpai; Bajpai 2Department Earth Sciences, Indian Institute Technology Roorkee, Uttarakhand 247667, V. Ravikant; Ravikant † 3Institute Instrumentation Centre, †Current...
Himalayacetus subathuensis is a new pakicetid archaeocete from the Subathu Formation of northern India. The type dentary has small mandibular canal indicating lack auditory specializations seen in more advanced cetaceans, and it Pakicetus-like molar teeth suggesting that fed on fish. significant because oldest known was found marine strata associated with fauna. extends fossil record whales about 3.5 million years back geological time, to middle part early Eocene [ approximately 53.5 ago...
Abstract The whale ear, initially designed for hearing in air, became adapted underwater less than ten million years of evolution. This study describes the evolution cetaceans, focusing on changes sound transmission mechanisms. Measurements were made 60 fossils whole or partial skulls, isolated tympanics, middle ear ossicles, and mandibles from all six archaeocete families. Fossil data compared with two families modern mysticete whales nine odontocete as well five noncetacean mammals....
Anthracobunidae is an Eocene family of large mammals from south Asia that commonly considered to be part the radiation gave rise elephants (proboscideans) and sea cows (sirenians). We describe a new collection anthracobunid fossils Middle rocks Indo-Pakistan more than doubles number known challenges their putative relationships, instead implying they are stem perissodactyls. Cranial, dental, postcranial elements allow revision species recognition genus. Analyses stable isotopes long bone...
The evolutionary success of mammals is rooted in their high metabolic rate. A rate sustainable thanks to efficient food processing and that turn facilitated by precise occlusion the teeth acquisition rhythmic mastication. These major innovations characterize most members Class Mammalia. Cetaceans are one few groups which has been secondarily lost. Most toothed whales have an increased number simple crowned similar along tooth row. Evolution toward these specializations began immediately...
Archaeological sites hold important clues to complex climate-human relationships of the past. Human settlements in peripheral zone Indus culture (Gujarat, western India) are considerable importance assessment past monsoon-human-subsistence-culture and their survival thresholds against climatic stress exerted by abrupt changes. During mature phase Harappan between ~4,600–3,900yrsBP, ~4,100±100yrsBP time slice is widely recognized as one major, arid-events imprinted innumerous well-dated...
A new primate fauna of early Eocene (Ypresian, approximately 52 Ma) age is reported from the Vastan Lignite Mine, District Surat, Gujarat, western India. From Indian subcontinent, this oldest known Cenozoic rocord as well largest single sample primates, consisting 3 fragmentary jaws and 4 isolated upper cheek teeth. The assemblage comprises at least three, but possibly taxa, which only two are being named here, an adapiform Marcgodinotius indicus n. gen. & sp., omomyid Vastanomys gracilis...
Research Article| January 01, 2009 EARLY DANIAN PLANKTIC FORAMINIFERA FROM CRETACEOUS-TERTIARY INTERTRAPPEAN BEDS AT JHILMILI, CHHINDWARA DISTRICT, MADHYA PRADESH, INDIA G. Keller; Keller 6 1Department of Geosciences, Princeton University, Princeton, NJ 08544, U.S.A. 6Correspondence author. E-mail: gkeller@princeton.edu Search for other works by this author on: GSW Google Scholar S. C. Khosla; Khosla 2Department Geology, Mohanlal Sukhadia Udaipur 310 002, India. R. Sharma; Sharma 3Department...
Dental morphology changes dramatically across the artiodactyl-cetacean transition, and it is generally assumed that this reflects evolutionary change from herbivory omnivory to carnivory. To test hypotheses regarding tooth function diet, we studied size position of wear facets on lower molars stable isotopes enamel samples. We found nearly all investigated Eocene cetaceans had dental different typical in ungulates isotope values indicating they hunted similar prey processed similarly. The...