197 research outputs found
Hysterangium bonobo: A newly described truffle species that is eaten by bonobos in the Democratic Republic of Congo
Many animals have been shown to eat fungi and most truffle-like fungi depend on animals for spore dispersal via mycophagy. Although these interactions are widespread, they are understudied in many habitats. In this study, we show that bonobos (Pan paniscus) forage and feed on an undescribed truffle species in the rainforests of the Democratic Republic of Congo. Based on morphological and molecular assessment of collections, we show that the species eaten by bonobos is a previously undescribed taxon described here as Hysterangium bonobo. This species is known in the local Bantu language (Bongando) as simbokilo and is used for baiting traps to catch several species of small mammals. Our findings highlight the need for further research into mycophagy and systematics of sequestrate fungi in Africa
Is early postnatal growth velocity, a proxy of minipubertal androgen action, related to adult second-to-fourth digit (2D:4D) ratios in men? A test in Cebu, Philippines
Methodological confounds of measuring urinary oxidative stress in wild animals
Abstract Biomarkers of oxidative stress (OS) are useful in addressing a wide range of research questions, but thus far, they have had limited application to wild mammal populations due to a reliance on blood or tissue sampling. A shift toward nonâinvasive measurement of OS would allow field ecologists and conservationists to apply this method more readily. However, the impact of methodological confounds on urinary OS measurement under field conditions has never been explicitly investigated. We combined a crossâsectional analysis with a field experiment to assess the impact of four potential methodological confounds on OS measurements: (1) time of sampling, (2) environmental contamination from foliage; (3) delay between sample collection and flashâfreezing in liquid nitrogen; and (4) sample storage of up to 15âmonths below â80°C. We measured DNA oxidative damage (8âhydroxyâ2â˛âdeoxyguanosine, 8âOHdG), lipid peroxidation (malondialdehyde, MDA), total antioxidant capacity (TAC), and uric acid (UA) in 167 urine samples collected from wild Zanzibar red colobus (Piliocolobus kirkii). We found that MDA was higher in samples collected in the morning than in the afternoon but there were no diurnal patterns in any of the other markers. Contamination of samples from foliage and length of time frozen at â80°C for up to 15âmonths did not affect OS marker concentrations. Freezing delay did not affect OS levels crossâsectionally, but OS values from individual samples showed only moderateâtoâgood consistency and substantial rankâorder reversals when exposed to different freezing delays. We recommend that diurnal patterns of OS markers and the impact of storage time before and after freezing on OS marker concentrations be considered when designing sampling protocols. However, given the high stability we observed for four OS markers subject to a variety of putative methodological confounds, we suggest that urinary OS markers provide a valuable addition to the toolkit of field ecologists and conservationists within reasonable methodological constraints
Alpha male status and availability of conceptive females are associated with high glucocorticoid concentrations in high-ranking male rhesus macaques (<i>Macaca mulatta</i>) during the mating season
Experimental evidence that female rhesus macaques (Macaca mulatta) perceive variation in male facial masculinity
Among many primate species, face shape is sexually dimorphic, and male facial masculinity has been proposed to influence female mate choice and male-male competition. However, whether conspecifics pay attention to facial masculinity has only been assessed in humans. Here, working with free-ranging rhesus macaques, Macaca mulatta, we used a two-alternative look-time experiment to test whether females perceive male facial masculinity. We presented 107 females with pairs of images of male faces â one more masculine and one more feminine â and recorded their looking behaviour. Females looked toward the masculine face longer than the feminine face in more trials than predicted by chance. Although there was no overall difference in average look-time between masculine and feminine faces across all trials, females looked significantly longer at masculine faces in a subset of trials for which the within-pair difference in masculinity was most pronounced. Additionally, the proportion of time subjects looked toward the masculine face increased as the within-pair difference in masculinity increased. This study provides evidence that female macaques perceive variation in male facial shape, a necessary condition for intersexual selection to operate on such a trait. It also highlights the potential impact of perceptual thresholds on look-time experiments
Second-to-fourth digit ratio (2D:4D) is unrelated to measures of somatic reproductive effort among young men from Cebu, the Philippines
Menarcheal timing is accelerated by favorable nutrition but unrelated to developmental cues of mortality or familial instability in Cebu, Philippines
Performance of the PADME calorimeter prototype at the DANE BTF
The PADME experiment at the DANE Beam-Test Facility (BTF) aims at
searching for invisible decays of the dark photon by measuring the final state
missing mass in the process , with undetected. The
measurement requires the determination of the 4-momentum of the recoil photon,
performed using a homogeneous, highly segmented BGO crystals calorimeter. We
report the results of the test of a 55 crystals prototype performed
with an electron beam at the BTF in July 2016
The implications of vehicle collisions for the Endangered endemic Zanzibar red colobus Piliocolobus kirkii
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