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Endothermy and activity in vertebrates.
Resting and maximal levels of oxygen consumption of endothermic vertebrates exceed those of ectotherms by an average of five- to tenfold. Endotherms have a much broader range of activity that can beExpand
The evolution of endothermy in mammals and birds: from physiology to fossils.
  • J. Ruben
  • Biology, Medicine
  • Annual review of physiology
  • 1995
TLDR
Endothermic warm­ bloodedness or, more correctly, endothermic homeothermy generally results from a combination of high resting, aerobically supported heat production rates in virtually all soft tissues, and insulation sufficient to retard excessive heat loss. Expand
The Evolution of Endothermy in Terrestrial Vertebrates: Who? When? Why?
TLDR
The fossil record of nonmammalian synapsids suggests that at least two Late Permian lineages possessed incipient respiratory turbinates, but this suggests that dinosaurs and nonornithurine birds generally lacked the capacity for high, avian‐like levels of sustained activity, although the aerobic capacity of theropods may have exceeded that of extant ectotherms. Expand
The Metabolic Status of Some Late Cretaceous Dinosaurs
TLDR
Analysis of the nasal region in fossils of three theropod dinosaurs and one ornithischian dinosaur showed that their metabolic rates were significantly lower than metabolic rates in modern birds and mammals. Expand
Cursoriality in bipedal archosaurs
TLDR
Surprisingly, Caudipteryx, described as a theropod dinosaur, possessed an anterior centre of mass and hindlimb proportions resembling those of cursorial birds, which may have implications for interpreting the locomotory status of its ancestors. Expand
MORPHOLOGICAL CORRELATES OF PREDATORY MODES IN THE COACHWHIP (MASTICOPHIS FLAGELLUM) AND ROSY BOA (LICHANURA ROSEOFUSCA)1
TLDR
Investigation of middorsal axial musculature and body conformation during lateral undulatory locomotion in the coachwhip, Masticophis flagellum and rosy boa, Licha- nura roseofusca indicates that constriction and locomotory speed may be mutually exclusive in snakes. Expand
Respiratory and Reproductive Paleophysiology of Dinosaurs and Early Birds
TLDR
The absence of nasal respiratory turbinates in these animals indicates that they were likely to have maintained reptile‐like (ectothermic) metabolic rates during periods of rest or routine activity, and persistent in vivo burial of their nests and apparent lack of egg turning suggests that clutch incubation by dinosaurs was more reptile- than birdlike. Expand
Aerobic and anaerobic metabolism during activity in snakes
  • J. Ruben
  • Biology
  • Journal of comparative physiology
  • 2004
TLDR
The data support conclusions that maximal energy production by these snakes correlates well with their respective modes of predation and defense, the highly active predators Coluber andMasticophis being capable of the greatest net energy production during activity. Expand
Lung Structure and Ventilation in Theropod Dinosaurs and Early Birds
TLDR
Paleontological and neontological evidence indicates that theropod dinosaurs possessed unmodified, bellowslike septate lungs that were ventilated with a crocodilelike hepatic-piston diaphragm mechanism, consistent with an ectothermic status for theropid dinosaurs and early birds. Expand
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