DOI: 10.5061/dryad.2v6wwpzmf
title: Foraging strategies, craniodental traits and interaction in the bite force of Neotropical frugivorous bats (Phyllostomidae: Stenodermatinae)

description: 1. Bats in the family Phyllostomidae exhibit great diversity in skull size
 and morphology that reflects the degree of resource division and
 ecological overlap in the group. In particular, the subfamily
 Stenodermatinae has high morphological diversification associated with
 cranial and mandibular traits that is associated with the ability to
 consume the full range of available fruits (soft and hard). 2. Was
 analyzed craniodental traits and their relationship to the bite force in
 343 specimens distributed in seven species of stenodermatine bats with two
 foraging strategies: nomadic and sedentary frugivory. We evaluated 19
 traits related to feeding and bite force in live animals by correcting
 bite force with body size. 3. We used a generalized linear model (GLM) and
 post hoc tests to determine possible relationships and differences between
 cranial traits, species, and sex. We also used Blomberg's K to
 measure the phylogenetic signal and Phylogenetic generalized least-squares
 (PGLS) to ensure the phylogenetic independence of the traits. 4. We found
 that smaller nomadic, A. anderseni and A. phaeotis have a similar bite
 force to the large species A. planirostris and A. lituratus; furthermore,
 P. helleri registered a bite force similar to that of the sedentary bat,
 S. giannae. Our study determined that all the features of the mandible and
 most of the traits of the skull have a low phylogenetic signal. Through
 the PGLS we found that the diet and several cranial features (mandibular
 toothrow length, dentary length, braincase breadth, mastoid breadth,
 greatest length of skull, condyloincisive length and condylocanine length)
 determined bite force performance among Stenodermatiane. 5. Our results
 reinforce that skull size is a determining factor in the bite force, but
 also emphasize the importance of its relationships with morphology,
 ecology, and phylogeny of the species, which gives us a better
 understanding of the evolutionary adaptions of this highly diverse
 Neotropical bat group.
description: We followed two procedures
 for collecting data. The first involved fieldwork in selected areas of the
 Colombian tropical dry forest (TDF) in the department of Tolima (Figure 1;
 Appendix 1) from February 2019 to January 2020. Conventional survey
 methodology was used, including mist-nets placed along trails within
 forest areas, at the edge of forest remnants, and near waterbodies. Each
 sampling night consisted of four standard-size mist nets (12 x 2.5 m) in
 the forest understory, eight nets (6 x 2.5 m) in the sub-canopy and a
 triple high net (30 x 7 m) in clearings, with a sampling intensity of
 36,288 m<sup>2</sup> nets/h, corresponding to 864 h in 144
 nights. The captured bats were handled according to the American Society
 of Mammalogists guidelines for the use of wild animals for research
 purposes (Sikes et al., 2016). After capture, the age, sex, and
 reproductive status were evaluated, and only adult males and adult
 non-pregnant, non-lactating females were used for measurements. Age was
 based on the degree of ossification of the wing joints. Reproductive
 status in females was determined by examining the nipples and palpation of
 the abdomen. Forearm length and body mass were recorded before euthanasia.
 Specimens were deposited in the biological collection of the University of
 Tolima CZUT-M (Ibagué, Colombia) and skulls were cleaned for craniodental
 morphometry (Table S1). The bite force of bats was
 measured using a portable digital fruit hardness tester Lutron FR 5120
 (made in Taiwan) with a capacity of 196.10 Newton and precision ± 0.05
 that corresponded to <i>in vivo</i> measurements of the
 maximal force. Bite force was recorded at the molars and measurements were
 repeated five times for each bat with a trial interval of at least 5 min
 following the method of Freeman & Lemen (2008). The maximum value
 of the five measurements was considered as the maximum bite force produced
 by that individual. The bite force of the species was calculated by
 averaging the maximum bite force of each individual. The second procedure for
 collecting data consisted of measurements of 16 craniodental traits and
 two body traits (Table 1, Figure 2) from voucher specimens in the
 Zoological Collection of the University of Tolima (CZUT; Ibagué,
 Colombia), Museo Javeriano de Historia Natural "Lorenzo Uribe,
 SJ" (MPUJ; Bogotá, Colombia) and Royal Ontario Museum (ROM; Ontario,
 Canada). The specimens from these biological collections are from 24
 localities in Colombia (Figure 1; Table S1). We verified that all were
 adult specimens based on the ossification of the phalange epiphyses in the
 wing (Dietz et al., 2007).<i> </i> Among frugivorous bats, two
 foraging categories adapted to fruit consumption were distinguished based
 on Soriano (2000): nomadic frugivorous, species whose strategy consists of
 feeding on trees with massive production of short-lived fruit, while
 sedentary bats have search itineraries more or less fixed every night and
 focus the consumption of fruits in plants with continuous production
 throughout the year. This classification involves a specialization towards
 a group of plants, reducing competition and generating a coevolution with
 plants and bats (Fleming, 1986; Giannini and Kalko, 2004). Stenodermatinae is the only
 subfamily with species that are either nomadic sedentary; therefore, these
 organisms constitute an excellent model to evaluate the skull traits
 involved in the consumption of contrasting fruits. We classified in our
 data set large-sized nomadic species with weight 55-65 g and medium to
 small-sized nomadic with weight 10-18 g. Although our size limit is
 arbitrary, it may have some biological relevance because <i>Artibeus
 planirostris</i> and <i>A. lituratus</i> are large bats
 with high dispersal capacity (Trevelin et al., 2013). Individuals captured
 in mistnets were placed in a clean cloth bag for up to four hours to
 obtain fecal samples, which were analyzed at a later date in the
 laboratory for seeds. The seeds were washed, examined with a dissection
 microscope and identified at the lowest possible taxonomic level (Table
 S2), and supplemented with bibliographic information from the registry
 (García-Herrera et al., 2019b).