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Giant beaver palaeoecology inferred from stable isotopes.

ABSTRACT: This is a multi-individual (n?=?11), stable carbon and nitrogen isotope study of bone collagen (?13Ccol and ?15Ncol) from the giant beaver (genus Castoroides). The now-extinct giant beaver was once one of the most widespread Pleistocene megafauna in North America. We confirm that Castoroides consumed a diet of predominantly submerged aquatic macrophytes. These dietary preferences rendered the giant beaver highly dependent on wetland habitat for survival. Castoroides' ?13Ccol and ?15Ncol do not support the hypothesis that the giant beaver consumed trees or woody plants, which suggests that it did not share the same behaviours as Castor (i.e., tree-cutting and harvesting). The onset of warmer, more arid conditions likely contributed to the extinction of Castoroides. Six new radiocarbon dates help establish the chronology of the northward dispersal of the giant beaver in Beringia, indicating a correlation with ice sheet retreat.

SUBMITTER: Plint T

PROVIDER: S-EPMC6509321 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature

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Giant beaver palaeoecology inferred from stable isotopes.

Plint Tessa T Longstaffe Fred J FJ Zazula Grant G

Scientific reports 20190509 1

This is a multi-individual (n = 11), stable carbon and nitrogen isotope study of bone collagen (δ13Ccol and δ15Ncol) from the giant beaver (genus Castoroides). The now-extinct giant beaver was once one of the most widespread Pleistocene megafauna in North America. We confirm that Castoroides consumed a diet of predominantly submerged aquatic macrophytes. These dietary preferences rendered the giant beaver highly dependent on wetland habitat for surviva ...[more]

PMID: 31073145

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Giant beaver palaeoecology inferred from stable isotopes.

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Giant beaver palaeoecology inferred from stable isotopes.

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