Polar dinosaurs on parade: a review of dinosaur migration

Bell, Phil R.; Snively, Eric

doi:10.1080/03115510802096101

Cited by 60 publications

(50 citation statements)

References 53 publications

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“…As in extant birds (13), prolonged nesting cycles may have made some environments improbable for successful reproduction and production of extra broods by some taxa, especially large dinosaurs whose incubation spanned the better part of a year. Speculation that neonates of large ornithischian dinosaurs (e.g., ceratopsians and hadrosaurids) made 2,600-to 3,200-km migrations from lower latitude nesting grounds to rich summer feeding grounds in the Arctic may have been infeasible because of unexpectedly short posthatching windows for seasonal travel (75)(76)(77). Finally, hypotheses regarding nest microenvironment (43, 61), eggshell gas conductance (61,78,79), embryonic physiology (45), reproductive effort, annual numbers of clutches and taxon generation times (21,80,81), and developmental mode (43) can be strengthened or formally tested in light of slower in ovo dinosaur development.…”

Section: Discussionmentioning

confidence: 99%

Dinosaur incubation periods directly determined from growth-line counts in embryonic teeth show reptilian-grade development

Erickson

Zelenitsky

Kay

et al. 2017

Proc. Natl. Acad. Sci. U.S.A.

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Birds stand out from other egg-laying amniotes by producing relatively small numbers of large eggs with very short incubation periods (average 11-85 d). This aspect promotes high survivorship by limiting exposure to predation and environmental perturbation, allows for larger more fit young, and facilitates rapid attainment of adult size. Birds are living dinosaurs; their rapid development has been considered to reflect the primitive dinosaurian condition. Here, nonavian dinosaurian incubation periods in both small and large ornithischian taxa are empirically determined through growthline counts in embryonic teeth. Our results show unexpectedly slow incubation (2.8 and 5.8 mo) like those of outgroup reptiles. Developmental and physiological constraints would have rendered tooth formation and incubation inherently slow in other dinosaur lineages and basal birds. The capacity to determine incubation periods in extinct egg-laying amniotes has implications for dinosaurian embryology, life history strategies, and survivorship across the Cretaceous-Paleogene mass extinction event.Dinosauria | teeth | embryology | Neornithes | extinction

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Section: Discussionmentioning

confidence: 99%

Dinosaur incubation periods directly determined from growth-line counts in embryonic teeth show reptilian-grade development

Erickson

Zelenitsky

Kay

et al. 2017

Proc. Natl. Acad. Sci. U.S.A.

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“…Could dinosaurs have withstood presumptively cool-to-cold ambient temperatures with rates of metabolism that were at the varanid level, or could these dinosaurs have evaded seasonally low temperatures through migration (51)? Migration appears to have been unlikely (45), which must have been the case in island New Zealand (54), although migratory herds may have led to the production of the enormous bone beds of hadrosaurs and ceratopsians in western North America (55). A biophysical analysis (56) indicated that dinosaurs Ͼ2 tons would have been able to maintain T b Ͼ 30°C by behavioral temperature regulation at latitudes up to 55 o N, even under the assumption that they had rates of metabolism equal to those of crocodiles, which, given their propensity for sit-and-wait predation, presumably are below those of varanids.…”

Section: Resultsmentioning

confidence: 99%

Resources and energetics determined dinosaur maximal size

McNab

2009

Proc. Natl. Acad. Sci. U.S.A.

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Some dinosaurs reached masses that were Ϸ8 times those of the largest, ecologically equivalent terrestrial mammals. The factors most responsible for setting the maximal body size of vertebrates are resource quality and quantity, as modified by the mobility of the consumer, and the vertebrate's rate of energy expenditure. If the food intake of the largest herbivorous mammals defines the maximal rate at which plant resources can be consumed in terrestrial environments and if that limit applied to dinosaurs, then the large size of sauropods occurred because they expended energy in the field at rates extrapolated from those of varanid lizards, which are Ϸ22% of the rates in mammals and 3.6 times the rates of other lizards of equal size. Of 2 species having the same energy income, the species that uses the most energy for mass-independent maintenance of necessity has a smaller size. The larger mass found in some marine mammals reflects a greater resource abundance in marine environments. The presumptively low energy expenditures of dinosaurs potentially permitted Mesozoic communities to support dinosaur biomasses that were up to 5 times those found in mammalian herbivores in Africa today. The maximal size of predatory theropods was Ϸ8 tons, which if it reflected the maximal capacity to consume vertebrates in terrestrial environments, corresponds in predatory mammals to a maximal mass less than a ton, which is what is observed. Some coelurosaurs may have evolved endothermy in association with the evolution of feathered insulation and a small mass.ectothermy ͉ endothermy ͉ energy expenditure ͉ varanid lizards W hether dinosaurs were endotherms or ectotherms has been controversial, as has been whether their thermal biology had any relevance to their attainment of extraordinarily large masses. Some authors (1-4) maintained that dinosaurs must have been endotherms because of their size, upright posture, bone structure, growth rates, presumed level of activity, and the high-latitude distributions of some species. Others (5-9) suggested that dinosaurs had a thermally constant body temperature as a result of large masses and small surface-to-volume ratios, but they probably had much lower levels of energy expenditure than would be expected of mammals (or birds) of the same mass, which was indicated by intermediate growth rates, narrow nasal passages, and unmodified, bellows-like septate lungs, which implies low ventilation rates. What most of these analyses have neglected is that the consumed resources ultimately control the energy expenditure and body size of organisms. Here, I propose that the maximal size of vertebrates is determined by resource abundance and how it is used by species.A Model. The maximal size of vertebrates is limited principally by the abundance and quality of the resources used to sustain their activities. The maximal daily field expenditure (K, kJ/d) of an individual varies with a variety of factors, including its mass, mobility, and the foods consumed. For example, the maximal expenditures (K h ) and...

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“…During the Late Cretaceous, Edmontosaurus was widely distributed as far north as paleoarctic Alaska, above 70°N latitude, and seasonal migrations of 2000 to 3000km were likely necessary to avoid exposure to prolonged (>3months) darkness and reduced availability of food (Clemens and Nelms, 1993;Bell and Snively, 2011). The climate of the likely southern destinations for Edmontosaurus, located between 51 and 41°N latitude, was similar to present-day New Orleans, LA, USA, characterized by hot, humid summers and mild winters (Dodson, 1971).…”

Section: Thermoregulatory Constraints On Activity In Endothermic and mentioning

confidence: 95%

“…Edmontosaurus is the archetype of presumably migratory dinosaurs (Bell and Snively, 2011). During the Late Cretaceous, Edmontosaurus was widely distributed as far north as paleoarctic Alaska, above 70°N latitude, and seasonal migrations of 2000 to 3000km were likely necessary to avoid exposure to prolonged (>3months) darkness and reduced availability of food (Clemens and Nelms, 1993;Bell and Snively, 2011).…”

Section: Thermoregulatory Constraints On Activity In Endothermic and mentioning

confidence: 99%

Heat storage in Asian elephants during submaximal exercise: behavioral regulation of thermoregulatory constraints on activity in endothermic gigantotherms

Rowe

Bakken

Ratliff

et al. 2013

Journal of Experimental Biology

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SUMMARYGigantic size presents both opportunities and challenges in thermoregulation. Allometric scaling relationships suggest that gigantic animals have difficulty dissipating metabolic heat. Large body size permits the maintenance of fairly constant core body temperatures in ectothermic animals by means of gigantothermy. Conversely, gigantothermy combined with endothermic metabolic rate and activity likely results in heat production rates that exceed heat loss rates. In tropical environments, it has been suggested that a substantial rate of heat storage might result in a potentially lethal rise in core body temperature in both elephants and endothermic dinosaurs. However, the behavioral choice of nocturnal activity might reduce heat storage. We sought to test the hypothesis that there is a functionally significant relationship between heat storage and locomotion in Asian elephants (Elephas maximus), and model the thermoregulatory constraints on activity in elephants and a similarly sized migratory dinosaur, Edmontosaurus. Pre-and post-exercise (N=37 trials) measurements of core body temperature and skin temperature, using thermography were made in two adult female Asian elephants at the Audubon Zoo in New Orleans, LA, USA. Over ambient air temperatures ranging from 8 to 34.5°C, when elephants exercised in full sun, ~56 to 100% of active metabolic heat production was stored in core body tissues. We estimate that during nocturnal activity, in the absence of solar radiation, between 5 and 64% of metabolic heat production would be stored in core tissues. Potentially lethal rates of heat storage in active elephants and Edmontosaurus could be behaviorally regulated by nocturnal activity.

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Polar dinosaurs on parade: a review of dinosaur migration

Cited by 60 publications

References 53 publications

Dinosaur incubation periods directly determined from growth-line counts in embryonic teeth show reptilian-grade development

Dinosaur incubation periods directly determined from growth-line counts in embryonic teeth show reptilian-grade development

Resources and energetics determined dinosaur maximal size

Heat storage in Asian elephants during submaximal exercise: behavioral regulation of thermoregulatory constraints on activity in endothermic gigantotherms

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