Resource partitioning among top predators in a Miocene food web

Abstract

The exceptional fossil sites of Cerro de los Batallones (Madrid Basin, Spain) contain abundant remains of Late Miocene mammals. From these fossil assemblages, we have inferred diet, resource partitioning and habitat of three sympatric carnivorous mammals based on stable isotopes. The carnivorans include three apex predators: two sabre-toothed cats (Felidae) and a bear dog (Amphicyonidae). Herbivore and carnivore carbon isotope (d 13 C) values from tooth enamel imply the presence of a woodland ecosystem dominated by C 3 plants. d 13 C values and mixing-model analyses suggest that the two sabre-toothed cats, one the size of a leopard and the other the size of a tiger, consumed herbivores with similar d 13 C values from a more wooded portion of the ecosystem. The two sabre-toothed cats probably hunted prey of different body sizes, and the smaller species could have used tree cover to avoid encounters with the larger felid. For the bear dog, d 13 C values are higher and differ significantly from those of the sabre-toothed cats, suggesting a diet that includes prey from more open woodland. Coexistence of the sabre-toothed cats and the bear dog was likely facilitated by prey capture in different portions of the habitat. This study demonstrates the utility of stable isotope analysis for investigating the behaviour and ecology of members of past carnivoran guilds.

What determines prey selection in owls? Roles of prey traits, prey class, environmental variables, and taxonomic specialization

“…Separation between predatory species in the food niche dimension has been studied extensively in the ecological literature (e.g., Schoener, and references therein; Kamler, Stenkewitz, Klare, Jacobsen, & Macdonald, ; Domingo, Domingo, Badgley, Sanisidro, & Morales, ; Symes, Wilson, Woodborne, Shaikh, & Scantlebury, ; Sheremetev, Rozenfeld, Dmitriev, Jargalsaikhan, & Enkh‐Amgalan, ; Källgren, Pedersen, & Nilssen, ), and a general pattern of increased prey size with increasing predator size has been recognized, for example, in numerous guilds of birds, carnivorous mammals, lizards, wasps, flies, beetles, and marine predators (e.g., Hespenheide, and references therein; Cohen, Pimm, Yodzis, & Saldaña, ; Carbone, Mace, Roberts, & Macdonald, ; Brose et al., ; Costa, ; Nakazawa, and references therein). However, numerous factors affect actual prey intake, including prey availability, the environment, and intensity of competition (e.g., Herrera & Hiraldo, ; Kappes, Weimerskirch, Pinaud, & Le Corre, ; Levesque, Juniper, & Marcus, ; Luiselli, ; Tsuruta & Goto, ).…”

Carnivoran resource and habitat use in the context of a Late Miocene faunal turnover episode

“…; Domingo, M. S. et al . ), but trophic fractionation must be accounted for before predator–prey inferences are undertaken. Fox‐Dobbs et al .…”

Long-Term Isotope Evidence on the Diet and Habitat Breadth of Pleistocene to Holocene Caprines in Thailand: Implications for the Extirpation and Conservation of Himalayan Gorals

“…The cut-off δ 13 C value of lower than −13 is adopted here for the mammals that lived in closed forests according to Cerling et al (1997aCerling et al ( , 2004, Kohn et al (2005), and Biasatti et al (2012). For the isotope comparison between large herbivores and predators, the fractionation factor of δ 13 C values for carnivores is adjusted by +1.3 (Clementz et al, 2009;Domingo et al, 2013). The faunal isotope baseline includes previously analyzed enamel samples from Pha Bong (Bocherens et al, 2017), Khok Sung (Suraprasit et al, 2018), and Tham Wiman Nakin (Pushkina et al, 2010;Bocherens et al, 2017) in Thailand, Nam Lot (Bacon et al, 2018b) in Laos, and Boh Dambang in Cambodia (Bacon et al, 2018c) (see Supplementary Material S4 for raw data).…”