Endothermy in fishes: a phylogenetic analysis of constraints, predispositions, and selection pressures

  title={Endothermy in fishes: a phylogenetic analysis of constraints, predispositions, and selection pressures},
  author={Barbara A. Block and John R. Finnerty},
  journal={Environmental Biology of Fishes},
  • B. Block, J. Finnerty
  • Published 1 July 1994
  • Biology, Environmental Science
  • Environmental Biology of Fishes
SynopsisEndothermy, the ability to raise body temperature by internal heat production, is unusual in teleost fishes and has only been documented within one suborder, the Scombroidei. Two separate modes of endothermy have evolved in the scombroidei; tunas warm their muscles, brain and viscera using heat exchangers in the circulation to these metabolically active tissues while billfishes and one primitive mackerel have a thermogenic organ situated beneath the brain. Both modes of endothermy… 
Evolution and Consequences of Endothermy in Fishes
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The evolution of mechanisms involved in vertebrate endothermy
  • L. LegendreD. Davesne
  • Biology, Environmental Science
    Philosophical Transactions of the Royal Society B
  • 2020
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Evidence for cranial endothermy in the opah (Lampris guttatus)
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Molecular Evolution of Cytochrome c Oxidase in High-Performance Fish (Teleostei: Scombroidei)
Focusing on a catalytic subunit of cytochrome c oxidase (COX II), it is found that the rate ratio of nonsynonymous (dN; amino acid changing)-to-synonymous (DS; silent) substitutions was not increased in lineages leading to the tuna but was significantly increased in the lineage preceding the billfish.
Whole‐body endothermy: ancient, homologous and widespread among the ancestors of mammals, birds and crocodylians
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Rates of mitochondrial DNA evolution in sharks are slow compared with mammals
Examination of mtDNA sequence variation for 13 species of sharks from two orders that are well represented in the fossil record to test the constancy hypothesis finds differences in mtDNA substitution rates among taxa indicate that it is inappropriate to use a calibration for one group to estimate divergence times or demographic parameters for another group.
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