1. Whole blood purine nucleotides were determined in 19 species of selachians and 27 species of marine teleosts. Concomitant ATP and GTP were revealed inside the erythrocytes of almost all species studied. 2. ATP seems to be the main potential modulator of oxygen affinity in rays, sharks and teleosts, and GTP was not detected in only two teleost species. 3. The mean erythrocytic NTP concentration and the ratio between NTP and intraerythrocytic Hb concentrations in rays were the lowest (2.3 mM and 0.6 respectively), increasing in sharks (3.8 mM and 1.0), and further in teleosts (5.9 mM and 2.1). 4. The intraerythrocytic phosphate contents probably reflect different adaptative strategies associated with the fish habits and habitats, and with the Root effect expression.
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http://dx.doi.org/10.1016/0300-9629(92)90142-d | DOI Listing |
Zoo Biol
October 2024
Oceanário de Lisboa, Lisbon, Portugal.
Accurate collection of biometric data is important for understanding the biology and conservation of marine organisms, including elasmobranch and teleost fish, both in nature and controlled environments where monitoring marine specimens' health is mandatory. Traditional methods involving specimen capture and handling are invasive, stressful, and disruptive. Some techniques like underwater visual census or laser photogrammetry have been used for noninvasive data collection, but they have limitations and biases.
View Article and Find Full Text PDFPalaontol Z
July 2024
Faculty of Earth Sciences, Geography and Astronomy, Department of Palaeontology, UZA 2, Geocentre, University of Vienna, Josef-Holaubek-Platz 2, 1090 Vienna, Austria.
J Fish Biol
December 2024
Department of Biological Sciences, Florida International University, North Miami, Florida, USA.
In June 2024, a large female oceanic whitetip shark (Carcharhinus longimanus) was observed near San Andres Island, Colombia, bearing at least 41 healed circular scars on its skin. These scars, resembling those left by cookiecutter sharks on large teleost species, suggest repeated predation events. Cookiecutter sharks typically leave one or two bite marks per prey item, with a small percentage showing five or more marks.
View Article and Find Full Text PDFDev Biol
December 2024
Life Sciences Institute and Faculty of Dentistry, University of British Columbia, Canada. Electronic address:
The dentition is critical to animal survival and teeth are present in modern vertebrates including teleost fish, sharks, amphibians, mammals and reptiles. The developmental processes that give rise to teeth are not just preserved through evolution but also share high level of similarity with the embryogenesis of other ectodermal organs. In this review we go beyond the embryonic phase of tooth development to life-long tooth replacement.
View Article and Find Full Text PDFCurr Biol
June 2024
Earth to Ocean Research Group, Department of Biological Sciences, Simon Fraser University, Burnaby, BC V5A 1S6, Canada.
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