Coprolites in natural traps: direct evidence of bone‐eating carnivorans from the Late Miocene Batallones‐3 site, Madrid, Spain

Abstract

We describe two carnivoran coprolites found in the pseudokarst natural carnivore trap of Batallones-3, from the Late Miocene of Spain. The larger one, comprising multiple indistinguishable fragments of broken and corroded bones, indicates that the producer of the dropping might have been highly capable of crushing the softer parts of large bones. On the other hand, the smaller one shows several relatively larger and more complete bone fragments, thus exhibiting a greater capacity to break and swallow large portions of bone. The external morphology of the large coprolite is similar to that of extant bears, whereas the smaller one more closely resembles that of the living insectivorous hyaenid Proteles in morphology, on the one hand, and that of the viverrid Genetta in size, on the other hand. We hypothesize that the amphicyonid Magerycion anceps was the producer of the large coprolite and the jackal-sized basal hyaenid Protictitherium crassum excreted the smaller one. Thus, we present the first direct evidence of a bone durophagous diet in the carnivorans of Batallones. □ Carnivora, fossil faeces, Iberian Peninsula, Late Miocene, pseudokarst.

X-ray tomographic microscopy of Eocene coprolites from Pipestone Springs Main Pocket, southwest Montana

“…The difficulty of identifying bone inclusions within the PSMP coprolites using µCT to a level beyond generic bone type was not a limitation of µCT itself, but rather a consequence of how much the bones were masticated and digested. Similar results were documented by Abella et al (2022), wherein they solely used µCT, but found many of the bones were not identifiable to a certain anatomical bone or taxon, and instead the authors relied on describing the general shape and features. Studies comparing the results of mechanical extraction and µCT analysis have encountered similar difficulties.…”

“…Evidence of osteophagy was based on abundant skeletal inclusions including fragments that appeared to belong to larger bones while others display depressions resembling partial tooth marks. Similar to the Class I PSMP coprolites, the larger specimen of the Spanish coprolites (specimen BAT-3′9.178) preserves irregular bone fragments not identifiable to a specific anatomical bone but does show evidence of digestive corrosion (Abella et al, 2022). The smaller coprolite (BAT-3′10.153), which is comparable in length to the PSMP Class I coprolites exhibits more complete skeletal elements and has a greater proportion of bone inclusions relative to the larger coprolite at the same locality (Abella et al, 2022;Figures 4, 6).…”

“…Similar to the Class I PSMP coprolites, the larger specimen of the Spanish coprolites (specimen BAT-3′9.178) preserves irregular bone fragments not identifiable to a specific anatomical bone but does show evidence of digestive corrosion (Abella et al, 2022). The smaller coprolite (BAT-3′10.153), which is comparable in length to the PSMP Class I coprolites exhibits more complete skeletal elements and has a greater proportion of bone inclusions relative to the larger coprolite at the same locality (Abella et al, 2022;Figures 4, 6). Several medium-sized carnivores were suggested as the producer of the smaller coprolite though the most probable was Protictitherium crassum, a member of Hyaenidae.…”

“…In a previous study employing comparable µCT methods, evidence of an osteophagous diet was inferred from two carnivoran coprolites of discrete sizes from the late Miocene, Spain (Abella et al, 2022). Evidence of osteophagy was based on abundant skeletal inclusions including fragments that appeared to belong to larger bones while others display depressions resembling partial tooth marks.…”

“…Examination of such fossils typically requires sub-sampling of the specimen, often employing destructive sampling techniques (e.g., disaggregation or dissolution) to either a portion of the specimen or its entirety (Bryant, 1970;Fry, 1970;Shillito et al, 2020). Recent studies have utilized non-destructive three-dimensional (3D) imaging techniques, such as x-ray tomographic microscopy (µCT) and synchrotron microtomography, to reveal macroscopic and microscopic inclusions that may otherwise be lost via more traditional methods (Bravo-Cuevas et al, 2017;Qvarnström et al, 2017;Wang et al, 2018;Romaniuk et al, 2020;Abella et al, 2022). Challenges with x-ray-based methodologies persist, however, often owing to the attributes of the sample.…”