Browse Items · NEOMED Bibliography Database

Thewissen et al. reply.

Replying to: J. H. Geisler & J. M. Theodor 458, 10.1038/nature07776 (2009)The analysis of Geisler and Theodor confirms our main phylogenetic result, that raoellids are, or include, the sister group to cetaceans. Their study expands on our findings by…

Tags: 2009, Bajpai Sunil, Clementz Mark T, Cooper Lisa Noelle, Department of Anatomy & Neurobiology, LETTERS to the editor, Nature, NEOMED College of Medicine, Thewissen J G M, Tiwari B N, WHALES

Organization and distribution of glomeruli in the bowhead whale olfactory bulb.

Although modern baleen whales (Mysticeti) retain a functional olfactory system that includes olfactory bulbs, cranial nerve I and olfactory receptor genes, their olfactory capabilities have been reduced to a great degree. This reduction likely…

Tags: 2015, Baleen whale, Brain, Cetacea, Department of Anatomy & Neurobiology, George John C, Kishida Takushi, Mysticeti, NEOMED College of Medicine, Olfactory marker protein, Olfactory receptor, PeerJ, Suydam Robert S, Thewissen J G M, Usip Sharon

Development and evolution of the unique cetacean dentition.

The evolutionary success of mammals is rooted in their high metabolic rate. A high metabolic rate is sustainable thanks to efficient food processing and that in turn is facilitated by precise occlusion of the teeth and the acquisition of rhythmic…

Tags: 2013, Armfield Brooke A, Bajpai Sunil, Cetacea, Cetacean, Department of Anatomy & Neurobiology, Evo-devo, NEOMED College of Medicine, Paleontology, PeerJ, Teeth, Thewissen J G M, Vinyard Christopher J, Zheng Zhengui

Validation of Growth Layer Group (GLG) depositional rate using daily incremental growth lines in the dentin of beluga (Delphinapterus leucas (Pallas, 1776)) teeth.

Counts of Growth Layer Groups (GLGs) in the dentin of marine mammal teeth are widely used as indicators of age. In most marine mammals, observations document that GLGs are deposited yearly, but in beluga whales, some studies have supported the view…

Tags: *Beluga Whale, 2018, Animals, Dentin/*growth & development, Department of Anatomy & Neurobiology, NEOMED College of Medicine, Ortiz Joseph D, PloS one, Suydam Robert S, Thewissen J G M, Tooth/*growth & development, Waugh David A

Severe Bone Loss as Part of the Life History Strategy of Bowhead Whales.

The evolution of baleen constituted a major evolutionary change that made it possible for baleen whales to reach enormous body sizes while filter feeding on tiny organisms and migrating over tremendous distances. Bowhead whales (Balaena mysticetus)…

Anthracobunids from the middle eocene of India and pakistan are stem perissodactyls.

Anthracobunidae is an Eocene family of large mammals from south Asia that is commonly considered to be part of the radiation that gave rise to elephants (proboscideans) and sea cows (sirenians). We describe a new collection of anthracobunid fossils…

Tags: *Fossils, 2014, Animals, Bajpai Sunil, Clementz Mark, Cooper Lisa Noelle, Department of Anatomy & Neurobiology, Dugong, Elephants, Hussain S Taseer, India, Madar Sandra I, NEOMED College of Medicine, Pakistan, PloS one, Seiffert Erik R, Thewissen J G M

Aquatic adaptation and the evolution of smell and taste in whales.

INTRODUCTION: While olfaction is one of the most important senses in most terrestrial mammals, it is absent in modern toothed whales (Odontoceti, Cetacea). Furthermore, behavioral evidence suggests that gustation is very limited. In contrast, their…

Tags: 2015, Agata Kiyokazu, Antarctic minke whale genome, Archaeoceti, Cetacea, Chemoreception, Department of Anatomy & Neurobiology, Hayakawa Takashi, Imai Hiroo, Kishida Takushi, NEOMED College of Medicine, Olfactory bulb, Thewissen J G M, Zoological letters

Structure of the external auditory meatus of the Bowhead whale (Balaena mysticetus) and its relation to their seasonal migration.

The external auditory meatus (EAM) in many species of mysticete whales is filled with a waxy ear plug. Though this lamellated structure is often used to age a whale, its formation and development remain undescribed. It is thought that growth layer…

Tags: 2019, bowhead whale, Department of Anatomy & Neurobiology, Epithelium, external auditory meatus, George John C, Journal of anatomy, McBurney Denise M, NEOMED College of Medicine, Rehorek Susan J, seasonality, Stimmelmayr Rafael, Suydam Robert, Thewissen J G M

Evolutionary aspects of the development of teeth and baleen in the bowhead whale.

In utero, baleen whales initiate the development of several dozens of teeth in upper and lower jaws. These tooth germs reach the bell stage and are sometimes mineralized, but toward the end of prenatal life they are resorbed and no trace remains…

Unique biochemical and mineral composition of whale ear bones.

Abstract Cetaceans are obligate aquatic mammals derived from terrestrial artiodactyls. The defining characteristic of cetaceans is a thick and dense lip (pachyosteosclerotic involucrum) of an ear bone (the tympanic). This unique feature is absent in…

Developmental basis for hind-limb loss in dolphins and origin of the cetacean bodyplan.

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 dolphins, the bud arrests and degenerates around the fifth gestational…

Tags: *Body Patterning, 2006, Animals, Bajpai S, Cell Polarity, Cohn M J, Department of Anatomy & Neurobiology, Developmental, Dolphins/*embryology/genetics/metabolism, Gene Expression Regulation, Heyning J, Hindlimb/cytology/*embryology/metabolism, Horton W E Jr, Limb Buds/cytology/embryology/metabolism, NEOMED College of Medicine, Phylogeny, Proceedings of the National Academy of Sciences of the United States of America, Stevens L S, Thewissen J G M

Whales originated from aquatic artiodactyls in the Eocene epoch of India.

Although the first ten million years of whale evolution are documented by a remarkable series of fossil skeletons, the link to the ancestor of cetaceans has been missing. It was known that whales are related to even-toed ungulates (artiodactyls), but…

Eocene evolution of whale hearing.

The origin of whales (order Cetacea) is one of the best-documented examples of macroevolutionary change in vertebrates. As the earliest whales became obligately marine, all of their organ systems adapted to the new environment. The fossil record…

Beyond thermoregulation: metabolic function of cetacean blubber in migrating bowhead and beluga whales.

The processes of lipid deposition and utilization, via the gene leptin (Lep), are poorly understood in taxa with varying degrees of adipose storage. This study examines how these systems may have adapted in marine aquatic environments inhabited by…

The spiral ganglion and Rosenthal's canal in beluga whales.

With the increase of human activity and corresponding increase in anthropogenic sounds in marine waters of the Arctic, it is necessary to understand its effect on the hearing of marine wildlife. We have conducted a baseline study on the spiral…

Review and experimental evaluation of the embryonic development and evolutionary history of flipper development and hyperphalangy in dolphins (Cetacea: Mammalia).

Cetaceans are the only mammals to have evolved hyperphalangy, an increase in the number of phalanges beyond the mammalian plesiomorphic condition of three phalanges per digit. In this study, cetaceans were used as a novel model to review previous…

Ontogeny of the Orbital Glands and Their Environs in the Pantropical Spotted Dolphin (Stenella attenuata: Delphinidae).

The nasolacrimal duct (NLD) connects the orbital (often associated with the Deep Anterior Orbital gland: DAOG, a.k.a. Harderian gland) and nasal regions in many tetrapods. Adult cetaceans are usually said to lack an NLD, and there is little agreement…

Sensory Hairs in the Bowhead Whale, Balaena mysticetus (Cetacea, Mammalia).

We studied the histology and morphometrics of the hairs of bowhead whales (Balaena mysticetus). These whales are hairless except for two patches of more than 300 hairs on the rostral tip of the lower lip and chin, the rostral tip of the upper lip,…

Development of the skull of the pantropical spotted dolphin (Stenella attenuata).

We describe the bony and cartilaginous structures of five fetal skulls of Stenella attenuata (pantropical spotted dolphin) specimens. The specimens represent early fetal life as suggested by the presence of rostral tactile hairs and the beginnings of…

Tags: 2011, Anatomical record (Hoboken, N.J. : 2007), Animals, Department of Anatomy & Neurobiology, Ear, Ear Ossicles/anatomy & histology/growth & development, Middle/anatomy & histology/growth & development, Moran Meghan M, NEOMED College of Medicine, Nummela Sirpa, Skull/*anatomy & histology/*growth & development, Stenella/*anatomy & histology/*growth & development, Thewissen J G M

Sound transmission in archaic and modern whales: anatomical adaptations for underwater hearing.

The whale ear, initially designed for hearing in air, became adapted for hearing underwater in less than ten million years of evolution. This study describes the evolution of underwater hearing in cetaceans, focusing on changes in sound transmission…

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