Search results for "Guinea"
showing 10 items of 412 documents
<p><strong><em>Chilocoris</em> <em>serratus</em> n. sp., the first burrower bug species (Hemiptera: Heteroptera: …
2016
The first burrower bug species recorded in Guinea-Bissau, Chilocoris serratus n. sp., is described and compared with morphologically related species. Additionally, an annotated checklist of Afrotropical species of the genus Chilocoris is provided.
Forage silica and water content control dental surface texture in guinea pigs and provide implications for dietary reconstruction.
2019
Significance Ingesta leave characteristic wear features on the tooth surface, which enable us to reconstruct the diet of extant and fossil vertebrates. However, whether dental wear is caused by internal (phytoliths) or external (mineral dust) silicate abrasives is controversially debated in paleoanthropology and biology. To assess this, we fed guinea pigs plant forages of increasing silica content (lucerne < grass < bamboo) without any external abrasives, both in fresh and dried state. Abrasiveness and enamel surface wear increased with higher forage phytolith content. Additionally, water loss altered plant material properties. Dental wear of fresh grass feeding was similar to lucerne brows…
Shape, size, and quantity of ingested external abrasives influence dental microwear texture formation in guinea pigs
2020
Food processing wears down teeth, thus affecting tooth functionality and evolutionary success. Other than intrinsic silica phytoliths, extrinsic mineral dust/grit adhering to plants causes tooth wear in mammalian herbivores. Dental microwear texture analysis (DMTA) is widely applied to infer diet from microscopic dental wear traces. The relationship between external abrasives and dental microwear texture (DMT) formation remains elusive. Feeding experiments with sheep have shown negligible effects of dust-laden grass and browse, suggesting that intrinsic properties of plants are more important. Here, we explore the effect of clay- to sand-sized mineral abrasives (quartz, volcanic ash, loess,…
Dental microwear texture gradients in guinea pigs reveal that material properties of the diet affect chewing behaviour
2021
ABSTRACT Dental microwear texture analysis (DMTA) is widely used for diet inferences in extant and extinct vertebrates. Often, a reference tooth position is analysed in extant specimens, while isolated teeth are lumped together in fossil datasets. It is therefore important to test whether dental microwear texture (DMT) is tooth position specific and, if so, what causes the differences in wear. Here, we present results from controlled feeding experiments with 72 guinea pigs, which received either fresh or dried natural plant diets of different phytolith content (lucerne, grass, bamboo) or pelleted diets with and without mineral abrasives (frequently encountered by herbivorous mammals in natu…
Factors controlling plankton community production, export flux, and particulate matter stoichiometry in the coastal upwelling system off Peru
2020
Eastern boundary upwelling systems (EBUS) are among the most productive marine ecosystems on Earth. The production of organic material is fueled by upwelling of nutrient-rich deep waters and high incident light at the sea surface. However, biotic and abiotic factors can modify surface production and related biogeochemical processes. Determining these factors is important because EBUS are considered hotspots of climate change, and reliable predictions of their future functioning requires understanding of the mechanisms driving the biogeochemical cycles therein. In this field experiment, we used in situ mesocosms as tools to improve our mechanistic understanding of processes controlling organ…
A new species and a new synonymy of the plant bug genusiFulvius/ifrom Japan (Hemiptera: Heteroptera: Miridae: Cylapinae).
2017
Fulvius Stål (Cylapinae: Fulviini) is a large plant bug genus, with more than 80 described species distributed throughout the world (Schuh, 1995; 2002–2014). In Japan, five species listed below have been recorded mostly from the subtropical Ryukyu arc (Yasunaga, 2000, 2001; Yasunaga & Miyamoto, 2006; Yasunaga et al., 2012). Our recent closer examinations of these Japanese species suggest that (1) what was previously identified as Fulvius dimidiatus Poppius represents an undescribed species, and (2) F. nakatai Yasunaga & Miyamoto described from Okinawa Island is evidently conspecific with F. subnitens Poppius that was described from New Guinea but is now known from pantropical zones …
Taxonomic review of the bifenestratus species group of the genus Fulvius Stål with descriptions of two new species (Hemiptera, Heteroptera, Miridae, …
2018
Two new species of the genus Fulvius Stål are described from the Philippines and Papua New Guinea. A taxonomic review of representatives of the F.bifenestratus species group, illustrations of the male genitalia, a color habitus image of each species, and a key to species of the group are provided.
The way wear goes: phytolith-based wear on the dentine–enamel system in guinea pigs (Cavia porcellus)
2019
The effect of phytoliths on tooth wear and function has been contested in studies of animal–plant interactions. For herbivores whose occlusal chewing surface consists of enamel ridges and dentine tissue, the phytoliths might particularly erode the softer dentine, exposing the enamel ridges to different occlusal forces and thus contributing to enamel wear. To test this hypothesis, we fed guinea pigs (Cavia porcellus; n = 36 in six groups) for threeweeks exclusively on dry or fresh forage of low(lucerne), moderate (fresh timothy grass) or very high (bamboo leaves) silica content representing corresponding levels of phytoliths. We quantified the effect of these treatments with measuremen…
Differential impact of two dominant Formica ant species (Hymenoptera, Formicidae) on subordinates in temperate Europe
2016
Competition is one of the basic mechanisms shaping ant assemblages. Dominant territorial species are known to restrictively influence the traits of subordinates in various ways. However, there could be differences in the effects of dominants due to differences in their colony structure, lifestyle and also behaviour. We tested this hypothesis in natural circumstances in an area where a Formica exsecta Nyl. supercolony neighbours a strong population of the European slave-maker F. sanguinea Latr. For the purpose of our study three different sites were selected: one dominated by F. exsecta, a neighbouring site dominated by F. sanguinea, and a third site where both species co-occurred. We analyz…
Fatty Acids of Microbial Origin in the Perirenal Fat of Rats (Rattus norvegicus domestica) and Guinea Pigs (Cavia porcellus) Fed Various Diets.
2020
Guinea pigs are assumed to practice caecotrophy to a higher degree than rats. Studies from leporids suggest that through the practice of caecotrophy, hindgut fermenting species could build up microbial fatty acids (FA) in body tissues. We hypothesized that microbial FA would be detectable in the body tissue of guinea pigs and rats, and this to a higher degree in guinea pigs. Twenty-four rats and guinea pigs were fed with four different pelleted diets (lucerne-, meat-, meat-bone-, insect-based) in groups of six animals for 8 weeks. Perirenal adipose tissue differed in FA composition between the species in spite of the common diets. FA typically associated with microbial activity (saturated F…