Bayesian hierarchical models suggest oldest known plant-visiting bat was omnivorous

Abstract

The earliest record of plant visiting in bats dates to the Middle Miocene of La Venta, the world's most diverse tropical palaeocommunity. Palynephyllum antimaster is known from molars that indicate nectarivory. Skull length, an important indicator of key traits such as body size, bite force and trophic specialization, remains unknown. We developed Bayesian models to infer skull length based on dental measurements. These models account for variation within and between species, variation between clades, and phylogenetic error structure. Models relating skull length to trophic level for nectarivorous bats were then used to infer the diet of the fossil. The skull length estimate for Palynephyllum places it among the larger lonchophylline bats. The inferred diet suggests Palynephyllum fed on nectar and insects, similar to its living relatives. Omnivory has persisted since the mid-Miocene. This is the first study to corroborate with fossil data that highly specialized nectarivory in bats requires an omnivorous transition.

Peramorphosis, an evolutionary developmental mechanism in neotropical bat skull diversity

“…This model of evolution predicts that fossils will be found representing more or less linear transitions from the ancestral insectivorous shape and towards each of the more derived and specialized conditions. This prediction is supported by the oldest fossil nectar bat Palynephyllum antimaster . The authors estimated that the extinct bat ate a mix of both insects and nectar prior to the highly specialized nectar‐only diet in the extant lonchophylline species.…”

“…This prediction is supported by the oldest fossil nectar bat Palynephyllum antimaster. 54 The authors estimated that the extinct bat ate a mix of both insects and nectar prior to the highly specialized nectar-only diet in the extant lonchophylline species. It is likely other fossils (such as preserved molar teeth) relevant to phyllostomids will have signatures of an omnivorous transition prior to diet specialization, as in this case a single molar tooth of P antimaster was sufficient to infer both its phylogenetic relationship and its diet.…”

A New Family of Large Omnivorous Bats (Mammalia, Chiroptera) from the Late Eocene of the Fayum Depression, Egypt, with Comments on Use of the Name “Eochiroptera”

“…Carnivorous bats often eat insects; insectivorous bats may occasionally eat small vertebrates, fruit, or nectar; frugivorous bats may supplement their diets with insects; and nectarivorous bats may also eat insects and fruit (Howell, 1974;Gardner, 1977;Freeman, 2000;Mello et al, 2004;Frick et al, 2009;Rex et al, 2010;Dumont et al, 2011;Santana et al, 2011b;Clare et al, 2014;Novaes et al, 2015;Yohe et al, 2015). Diets of some (perhaps many) bat species may also shift dramatically with season (Howell, 1974;Sosa and Soriano, 1996;Mello et al, 2004;Richards et al, 2008;Rex et al, 2010;Clare et al, 2014).…”

“…However, most bat species appear to have morphological specializations for fruit, nectar, or animal-based diets (Freeman, 1984(Freeman, , 2000Dumont, 2003;Swartz et al, 2003, Winter andVon Helverson, 2003) and rely entirely or primarily on one type of food at least in some seasons of the year (Gardner, 1977;Freeman, 1984Freeman, , 2000, thus allowing the categorizations described above. Clear exceptions exist, however-true omnivorous bats that routinely consume a variety of food types including both animal and plant products (Gardner, 1977;Arkins et al, 1999;Lloyd, 2001;Rex et al, 2010;Dumont et al, 2011;Clare et al, 2014;Yohe et al, 2015). These taxa all belong to the Neotropical family Phyllostomidae and the related New Zealand/Australian endemic family Mystacindae.…”

Dietary and body mass reconstruction of the Miocene neotropical batNotonycteris magdalenensis(Phyllostomidae) from La Venta, Colombia

“…The La Venta bat community includes representatives of six families, including extinct representatives of the family Phyllostomidae (Notonycteris magdalenensis, N. sucharadeus, Palynephyllum antimaster), and the oldest evidence of modern species of families Noctilionidae (Noctilio albiventris) and Thyropteridae (Thyroptera lavali) (Czaplewski 1997, Czaplewski et al 2003. P. antimaster represents the earliest phytophagous bat in the New World, a dietary strategy providing a key evolutionary innovation for the order (Czaplewski et al 2003, Yohe et al 2015).…”