Stable isotope analysis (SIA) has emerged as a common tool in ecology and has proven especially useful in the study of animal diet, habitat use, movement, and physiology. SIA has been vigorously applied to the study of marine mammals, because most species live in habitats or undergo large migrations/movements that make them difficult to observe. Our review supplies a complete list of published SIA contributions to marine mammal science and highlights informative case examples in four general research areas: (1) physiology and fractionation, (2) foraging ecology and habitat use, (3) ecotoxicology, and (4) historic ecology and paleoecology. We also provide a condensed background of isotopic nomenclature, highlight several physiological considerations important for accurate interpretation of isotopic data, and identify research areas ripe for future growth. Because it is impossible to conduct controlled laboratory experiments on most marine mammal species, future studies in marine mammal ecology must draw on isotopic data collected from other organisms and be cognizant of key assumptions often made in the application of SIA to the study of animal ecology. The review is designed to be accessible to all audiences, from students unfamiliar with SIA to those who have utilized it in published studies.

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Using stable isotope biogeochemistry to study marine mammal ecology

Although mass extinctions probably account for the disappearance of less than 5% of all extinct species, the evolutionary opportunities they have created have had a disproportionate effect on the history of life. Theoretical considerations and simulations have suggested that the empty niches created by a mass extinction should refill rapidly after extinction ameliorates. Under logistic models, this biotic rebound should be exponential, slowing as the environmental carrying capacity is approached. Empirical studies reveal a more complex dynamic, including positive feedback and exponential growth phase during recoveries. Far from a model of refilling ecospace, mass extinctions appear to cause a collapse of ecospace, which must be rebuilt during the recovery. Other generalities include the absence of a clear correlation between the magnitude of extinction and the pace of recovery, or the resulting ecological and evolutionary disruption; the presence of a survival interval, with few originations, immediately following an extinction and preceding the recovery phase; and the presence of many lineages which persist through an extinction event only to disappear during the subsequent recovery. Several recoveries encompass numerous missing lineages, groups which are found before the extinction, then later in the recovery, but are missing during the initial survival-recovery phase. The limited biogeographic studies of recoveries suggest considerable variability between regions.

Lessons from the Past: Biotic Recoveries from Mass Extinctions

Strontium and stable isotope evidence for diet and mobility in Roman Gloucester, UK

RATIONALE
Oxygen isotope analysis of archaeological human dental enamel is widely used as a proxy for the drinking water composition (δ18ODW) of the individual and thus can be used as an indicator of their childhood place of origin. In this paper we demonstrate the robustness of structural carbonate oxygen isotope values (δ18OC) in bioapatite to preserve the life signal of human tooth enamel by comparing it with phosphate oxygen isotope values (δ18OP) derived from the same archaeological human tooth enamel samples.
METHODS
δ18OC analysis was undertaken on 51 archaeological tooth enamel samples previously analysed for δ18OP values and strontium isotopes. δ18OC values were determined on a GV IsoPrime dual inlet mass spectrometer, following a series of methodological tests to assess: (1) The reaction time needed to ensure complete release of CO2 from structural carbonate in the enamel; (2) The effect of an early pre-treatment with dilute acetic acid to remove diagenetic carbonate; (3) Analytical error; (4) Intra-tooth variation; and (5) Diagenetic alteration.
RESULTS
This study establishes a direct relationship between δ18OC and δ18OP values from human tooth enamel (δ18OP = 1.0322 × δ18OC – 9.6849). We have combined this equation with the drinking water equation of Daux et al. (J. Hum. Evol. 2008, 55, 1138) to allow direct calculation of δ18ODW values from human bioapatite δ18OC (δ18ODW = 1.590 × δ18OC – 48.634).
CONCLUSIONS
This is the first comprehensive study of the relationship between the ionic forms of oxygen (phosphate oxygen and structural carbonate) in archaeological human dental enamel. The new equation will allow direct comparison of data produced by the different methods and allow drinking water values to be calculated from structural carbonate data with confidence

The oxygen isotope relationship between the phosphate and structural carbonate fractions of human bioapatite

The Early Triassic ammonoid recovery: Paleoclimatic significance of diversity gradients

https://hal.archives-ouvertes.fr/halsde-00341152/document

Oxygen isotope fractionation between human phosphate and water revisited

Cenozoic long-term terrestrial climatic evolution in Germany tracked by δ18O of rodent tooth phosphate

Oxygen isotope compositions of phosphate from Middle Miocene-Early Pliocene marine vertebrates of Peru

This work presents two examples of palaeobiogeographic reconstruction using the Interactive Data Language® (IDL). Although this meta-language is devoted to geoscientists and offers an array of easily usable tools, few palaeontologists actually use it. Our purpose is to illustrate how the IDL can be used to generate clear and direct visualizations of simulation results and interpolation methods for personal Geographic Information Systems (GIS). The first example is a paleogeographic simulation of the biodiversity evolution of planktonic species (and especially ammonoids) in the Early Triassic. Principal results of this global scale simulation are that the formation of a marine latitudinal gradient of species richness depends on the shape and magnitude of the Sea Surface Temperature (SST) gradient, and the geographic location of the group’s ancestor. Thus, the recovery pattern of Early Triassic ammonoids species richness can be simulated and explained by a general increasing trend in steepness of the SST gradient. The second example describes a custom-designed GIS for large European Neogene continental mammals. Species richness and ecomorphologic parameters are interpolated, monitored in several ways, and discussed. Comparisons with the presentday distribution of large European mammals are also drawn and allow us to recognize that a broad North/South aridity gradient already existed by the Late Miocene with more open environments in Southern Europe.

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Marie-Anne Héran

Papers

Oxygen isotope fractionation between human phosphate and water revisited

Cenozoic long-term terrestrial climatic evolution in Germany tracked by δ18O of rodent tooth phosphate

Oxygen isotope compositions of phosphate from Middle Miocene-Early Pliocene marine vertebrates of Peru

Triassic and cenozoic palaeobiogeography: two case studies in quantitative modelling using idl®