scholarly journals Morphological variation of the relictual alveolar structures in the mandibles of baleen whales

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11890
Author(s):  
Carlos Mauricio Peredo ◽  
Nicholas D. Pyenson
Keyword(s):  
Morphological Variation ◽  
Potential Role ◽  
In Utero ◽  
The Body ◽  
Baleen Whales ◽  
Histological Studies ◽  
Feeding Process ◽  
Filter Feeders ◽  
Taxonomic Groups ◽  
Tooth Buds

Living baleen whales (mysticetes) are bulk filter feeders that use keratinous baleen plates to filter food from prey laden water. Extant mysticetes are born entirely edentulous, though they possess tooth buds early in ontogeny, a trait inherited from toothed ancestors. The mandibles of extant baleen whales have neither teeth nor baleen; teeth are resorbed in utero and baleen grows only on the palate. The mandibles of extant baleen whales also preserve a series of foramina and associated sulci that collectively form an elongated trough, called the alveolar groove. Despite this name, it remains unclear if the alveolar groove of edentulous mysticetes and the dental structures of toothed mammals are homologous. Here, we describe and quantify the anatomical diversity of these structures across extant mysticetes and compare their variable morphologies across living taxonomic groups (i.e., Balaenidae, Neobalaenidae, Eschrichtiidae, and Balaenopteridae). Although we found broad variability across taxonomic groups for the alveolar groove length, occupying approximately 60–80 percent of the mandible’s total curvilinear length (CLL) across all taxa, the relictual alveolar foramen showed distinct patterns, ranging between 15–25% CLL in balaenids, while ranging between 3–12% CLL in balaenopterids. This variability and the morphological patterning along the body of the mandible is consistent with the hypothesis that the foramina underlying the alveolar groove reflect relictual alveoli. These findings also lay the groundwork for future histological studies to examine the contents of these foramina and clarify their potential role in the feeding process.

Noise generated by the jaw actions of feeding fin whales

1993 ◽  
Vol 71 (12) ◽  
pp. 2546-2550 ◽  
Author(s):  
Paul F. Brodie
Keyword(s):  
The Body ◽  
Synovial Joint ◽  
Body Movements ◽  
Animal Kingdom ◽  
Balaenoptera Physalus ◽  
Baleen Whales ◽  
Fin Whale ◽  
Filter Feeders ◽  
Fin Whales

The fin whale (Balaenoptera physalus) is representative of baleen whales, which feed by engulfing up to 70 t of seawater in an elastic throat pouch, prior to filtering. This represents (i) the greatest biomechanical action in the animal kingdom, and (ii) a deviation from the flowthrough design of fishing trawls, most filter-feeders, and sampling devices. Based upon observations of fresh carcasses, it is proposed that during the brief period at full gape agile prey may be startled and retained within the pouch by noise: a synovial joint-crack generated during realignment of the tips of the mandibles. It is argued that the previous detection of nonvocal sounds, attributed to the body movements of feeding fin whales, may also include noise resulting from this action.

scholarly journals Use of maternal reserves as a lactation strategy in large mammals

2000 ◽  
Vol 59 (1) ◽  
pp. 99-106 ◽  
Author(s):  
Olav T. Oftedal
Keyword(s):  
Milk Production ◽  
Energy Content ◽  
The Body ◽  
Large Mammals ◽  
Body Protein ◽  
Baleen Whales ◽  
Fur Seals ◽  
Gross Energy ◽  
Taxonomic Groups ◽  
Large Animals

The substrate demands of lactation must be met by increased dietary intake or by mobilization of nutrients from tissues. The capacity of animals to rely on stored nutrients depends to a large extent on body size; large animals have greater stores, relative to the demands of lactation, than do small animals. The substrate demands of lactation depend on the composition and amount of milk produced. Animals that fast or feed little during lactation are expected to produce milks low in sugar but high in fat, in order to minimize needs for gluconeogenesis while sustaining energy transfers to the young. The patterns of nutrient transfer are reviewed for four taxonomic groups that fast during part of or throughout lactation: sea lions and fur seals (Carnivora: Otariidae), bears (Carnivora: Ursidae), true seals (Carnivora: Phocidae) and baleen whales (Cetacea: Mysticeti). All these groups produce low-sugar high-fat milks, although the length of lactation, rate of milk production and growth of the young are variable. Milk protein concentrations also tend to be low, if considered in relation to milk energy content. Maternal reserves are heavily exploited for milk production in these taxa. The amounts of lipid transferred to the young represent about one-fifth to one-third of maternal lipid stores; the relative amount of the gross energy of the body transferred in the milk is similar. Some seals and bears also transfer up to 16–18 % of the maternal body protein via milk. Reliance on maternal reserves has allowed some large mammals to give birth and lactate at sites and times far removed from food resources.

scholarly journals Tentacle Morphological Variation Coincides with Differential Expression of Toxins in Sea Anemones

Toxins ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 452
Author(s):  
Lauren M. Ashwood ◽  
Michela L. Mitchell ◽  
Bruno Madio ◽  
David A. Hurwood ◽  
Glenn F. King ◽  
...  
Keyword(s):  
Differential Expression ◽  
Morphological Variation ◽  
Expression Profiles ◽  
The Body ◽  
Sea Anemones ◽  
Tissue Specific ◽  
Venom Composition ◽  
Specific Manner ◽  
Branched Structures ◽  
Morphological Variants

Phylum Cnidaria is an ancient venomous group defined by the presence of cnidae, specialised organelles that serve as venom delivery systems. The distribution of cnidae across the body plan is linked to regionalisation of venom production, with tissue-specific venom composition observed in multiple actiniarian species. In this study, we assess whether morphological variants of tentacles are associated with distinct toxin expression profiles and investigate the functional significance of specialised tentacular structures. Using five sea anemone species, we analysed differential expression of toxin-like transcripts and found that expression levels differ significantly across tentacular structures when substantial morphological variation is present. Therefore, the differential expression of toxin genes is associated with morphological variation of tentacular structures in a tissue-specific manner. Furthermore, the unique toxin profile of spherical tentacular structures in families Aliciidae and Thalassianthidae indicate that vesicles and nematospheres may function to protect branched structures that host a large number of photosynthetic symbionts. Thus, hosting zooxanthellae may account for the tentacle-specific toxin expression profiles observed in the current study. Overall, specialised tentacular structures serve unique ecological roles and, in order to fulfil their functions, they possess distinct venom cocktails.

Blood Circulation in Insect Wings

1964 ◽  
Vol 96 (1-2) ◽  
pp. 98-98 ◽  
Author(s):  
J. W. Arnold
Keyword(s):  
Blood Circulation ◽  
The Body ◽  
Insect Wings ◽  
Wing Structure ◽  
Wing Veins ◽  
Taxonomic Groups ◽  
Modified Forms ◽  
Surrounding Membrane

Despite their inert appearance, the wings of insects are living appendages and are supplied with blood. This is true for definitive wings as well as for developing ones, and for modified wings such as tegmina, elytra, hemelytra, and halteres as for those that are specialized for flight. Typically the blood circulates only through the wing veins, but in some insects it escapes into the surrounding membrane in certain areas, and in highly modified forms it may be entirely unconfined. The course of circulation is basically the same in the wings of most insects. It flows outward from the body in the costo-medial veins, moves toward the posterior margins via cross-veins, and returns to the body through the cubito-anal veins and axillary cord. However, rhe precise route followed is highly variable concomitant with distinctive patterns of venation in different taxonomic groups and with wing structure. This is illustrated for a number of orders.

scholarly journals Immunity against COVID-19: Potential role of Ayurveda: A Review

2021 ◽  
Vol 8 (3) ◽  
pp. 989-992
Author(s):  
Mula Ram Suthar ◽  
◽  
Manjry Anshumala Barla ◽  
Rakesh Roushan ◽  
◽  
...  
Keyword(s):  
Infectious Disease ◽  
Potential Role ◽  
Defense Mechanism ◽  
Well Being ◽  
Communicable Diseases ◽  
The Body ◽  
Disease Concept ◽  
First Case ◽  
Modern Perspective

The Severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) is an infectious disease caused by coronavirus disease 2019 (COVID-19) and has affected people's lives globally, since first case was detected in Wuhan, China in December 2019. The coronavirus pandemic has turned the world’s attention to the immune system, the body’s defense mechanism against disease. Concept of Ojas is well explained in all ayurvedic classics, in modern perspective it is considered as immunity (Vyadhikshamatava). Ojas is necessary for well-being of the body, and mind. In Ayurveda textbook, the epidemics and along with their management are discussed under the term of Janapadodhvansa. The preventive and curative treatments for communicable diseases of the Janapadodhvansa (epidemics) are Panchkarma (five bio-purification therapies), Rasayana Chikitsa (rejuvenation treatment), Achara Rasayana (good conducts), and migrate to the place, free from communicable diseases. The intake of all types Rasayanas leads to increase of Ojas and reduce all psychological (mainly stress and emotional) disorder, thereby causes increase immunity responses and help to fight against covid-19. Key Words: Ayurveda, Covid-19, Immunity, Janapadodhvansa, Ojas, Rasayana Chikitsa.

scholarly journals Infants and Mothers

2018 ◽  
Author(s):  
Rebecca Gowland
Keyword(s):  
Gender Identity ◽  
Cultural Beliefs ◽  
In Utero ◽  
The Body ◽  
Newborn Baby ◽  
Social Forces ◽  
Social Worlds ◽  
The Past ◽  
Blank Slate ◽  
Medical Writings

There is a burgeoning interest in the variable ways in which past and present societies construct the notion of foetal and infant entities and the beginnings of personhood. The newborn baby has often been conceptualized as a tabular rasa, a blank slate, which progressively becomes moulded by biological, environmental, and social forces. Within this construct the infant is likened to clay and indeed this analogy is made explicit in early medical writings. However, infants are conceived and born into social worlds and these impact on their nascent identities whilst still in utero. Likewise, cultural beliefs concerning gender identity, reproduction, and the pregnant body may have biological repercussions for the developing foetus. This chapter aims to explore the interplay between the body and society in the formation and conceptualization of infant bodies in the past.

scholarly journals The Protective Effect of Exercise in Neurodegenerative Diseases: The Potential Role of Extracellular Vesicles

Cells ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 2182 ◽  
Author(s):  
Oliver K Fuller ◽  
Martin Whitham ◽  
Suresh Mathivanan ◽  
Mark A Febbraio
Keyword(s):  
Physical Activity ◽  
Extracellular Vesicles ◽  
Potential Role ◽  
The Body ◽  
Therapeutic Effects ◽  
Health And Wellbeing ◽  
Systemic Factors ◽  
Diabetes And Obesity

Physical activity has systemic effects on the body, affecting almost every organ. It is important not only for general health and wellbeing, but also in the prevention of diseases. The mechanisms behind the therapeutic effects of physical activity are not completely understood; however, studies indicate these benefits are not confined to simply managing energy balance and body weight. They also include systemic factors which are released into the circulation during exercise and which appear to underlie the myriad of benefits exercise can elicit. It was shown that along with a number of classical cytokines, active tissues also engage in inter-tissue communication via extracellular vesicles (EVs), specifically exosomes and other small EVs, which are able to deliver biomolecules to cells and alter their metabolism. Thus, EVs may play a role in the acute and systemic adaptations that take place during and after physical activity, and may be therapeutically useful in the treatment of a range of diseases, including metabolic disorders such as type 2 diabetes and obesity; and the focus of this review, neurological disorders such as Alzheimer’s disease.

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