22 research outputs found

    Mating and aggregative behaviors among basal hexapods in the Early Cretaceous

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    Among the many challenges in paleobiology is the inference and reconstruction of behaviors that rarely, if ever, leave a physical trace on the environment that is suitable for fossilization. Of particular significance are those behaviors tied to mating and courtship, individual interactions critical for species integrity and continuance, as well as those for dispersal, permitting the taxon to expand its distribution as well as access new habitats in the face of local or long-term environmental change. In this context, two recently discovered fossils from the Early Cretaceous amber of Spain (ca. 105 mya) give a detailed view of otherwise fleeting ethologies in Collembola. These occurrences are phylogenetically spaced across the class, and from species representing the two major clades of springtailsÐSymphypleona and Entomobryomorpha. Specifically, we report unique evidence from a symphypleonan male (Pseudosminthurides stoechus SaÂnchez-GarcÔÂa & Engel, 2016) with modified antennae that may have functioned as a clasping organ for securing females during mating on water's surface, and from an aggregation of entomobryomorphan individuals (Proisotoma communis SĂĄnchez-GarcĂ­a & Engel, 2016) purportedly representing a swarming episode on the forest floor. We demonstrate that the mating behavioral repertoire in P. stoechus, which is associated with considerable morphological adaptations, likely implied elaborate courtship and maneuvering for guarantee sperm transfer in an epineustic species. These discoveries reveal significant behaviors consistent with modern counterparts and a generalized stasis for some ancient hexapod ethologies associated with complex mating and courtship and social or pre-social aggregations, so critical to specific constancy and dispersal

    New Species Of Melittophilous Pseudocyphoderus From Costa rica And Remarks On Taxonomy Collembola Cyphoderidae

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    Volume: 88Start Page: 229End Page: 23

    Five new species of Orchesellini from Central Mexico (Collembola: Entomobryidae: Orchesellinae)

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    Volume: 86Start Page: 808End Page: 82

    New records of springtails in New Zealand pasture: how well are our pastoral invertebrates known?

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    Twenty-four collembolan species are recorded from improved pastures and clovers in New Zealand, of which 17 can be named to species or probable species, the others only to genus. Of the 17 named species, nine have been recorded before from New Zealand but the other eight are new records for the country. All named species are considered as introduced to New Zealand, probably originally from Europe and are unlikely to colonise native habitats. As all named species reported as new records can be abundant at times, this indicates poor knowledge of a major part of New Zealand's agricultural fauna. Collembola are a group of important microarthropod detritivores that make a significant contribution to ecosystem services. The absence so far of quantification of the contribution this and other soil groups make to ecological resilience and function is a serious problem

    Increased protein intake affects pro-opiomelanocortin (POMC) processing, immune function and IGF signaling in peripheral blood mononuclear cells of home-dwelling old subjects using a genome-wide gene expression approach

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    Abstract Background: Adequate protein intake among older adults is associated with better health outcomes such as immune function and metabolic regulation of skeletal muscle, but conflicting results make it difficult to define the optimal intake. To further understand the impact of protein intake on metabolic processes, the aim of the study was to explore genome-wide gene expression changes in peripheral blood mononuclear cells (PBMCs) in home-dwelling old subjects after increased protein intake for 12 weeks. Method: In a parallel double-blind randomized controlled intervention study, subjects (≄ 70 years) received a protein-enriched milk (2 × 20 g protein/day, n = 14, mean (±SD) age 76.9 ± 4.9 years) or an isocaloric carbohydrate drink (n = 17, mean (±SD) age 77.7 ± 4.8 years) for breakfast and evening meal for 12 weeks. PBMCs were isolated before and after the intervention. Microarray analysis was performed using Illumina technology. Serum levels of gut peptides and insulin growth factor (IGF)-1 were also measured. Results: In total 758 gene transcripts were regulated after increased protein intake, and 649 gene transcripts were regulated after intake of carbohydrates (p < 0.05). Forty-two of these genes were overlapping. After adjusting for multiple testing, 27 of the 758 gene transcripts were regulated (FDR, q-value < 0.25) after protein intake. Of these 25 were upregulated and two downregulated. In particular, genes and signaling pathways involved in pro-opiomelanocortin (POMC) processing, immune function, and IGF signaling were significantly altered. Conclusions: PBMCs can be used to study gene expression changes after long-term protein intake, as many signaling pathways were regulated after increased protein intake. The functional significance of these findings needs to be further investigated
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