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1. Spatial variation in phylogenetic diversity of communities of Atlantic Forest harvestmen (Opiliones, Arachnida)

   https://doi.org/10.1111/icad.12356  

   Nogueira, André do Amaral ; Bragagnolo, Cibele ; DaSilva, Márcio Bernardino ; Carvalho, Leonardo Sousa ; Benedetti, Alípio Rezende ; Pinto‐da‐Rocha, Ricardo ; Basset, ed., Yves ; Buddle, ed., Chris ( June 2019 , Insect Conservation and Diversity)

   The study of diversity has become increasingly sophisticated, including the use of measures of phylogenetic diversity.

   We calculate the spatial variation in species richness, taxonomic beta diversity, and alpha and beta phylogenetic diversity (PDαandPDβ, respectively) of Atlantic Forest harvestman communities using a data set containing 556 species from 68 sites, distributed in 12 Brazilian states.

   We compare the congruence of phylogenetic and taxonomic diversity patterns, and also comparePDαwith null model expectations, to check for phylogenetic clustering or overdispersion in communities.

   Species richness andPDαare correlated, peaking in southern and south‐eastern coastal sites and decreasing towards the interior and towards the north‐east.PDαin north‐eastern sites was higher than expected, while a clustered phylogenetic pattern characterised most other sites.

   Communities in the southern and south‐eastern regions were dominated by species from the large family Gonyleptidae, presenting a high richness and a lowPDα. As the dominance of Gonyleptidae decreased towards the north, where local communities have fewer species, but a higherPDα, they contain representatives of other families. The beta diversity was more sensitive to the compositional changes involving closely related Gonyleptidae species, whilePDβis more influenced by deeper phylogenetic compositional changes, between more distant lineages.

   Phylogenetic diversity may be of special importance to assess the conservation value of distantly related lineages. These species‐poor groups are less likely to influence taxonomic‐based diversity analyses, but their importance for conservation arises from their phylogenetic distinctiveness, captured byPDαandPDβmeasures.

    

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2. Taxonomic and functional diversity change is scale dependent

   https://doi.org/10.1038/s41467-018-04889-z  

   Jarzyna, Marta_A ; Jetz, Walter ( July 2018 , Nature Communications)

   Estimates of recent biodiversity change remain inconsistent, debated, and infrequently assessed for their functional implications. Here, we report that spatial scale and type of biodiversity measurement influence evidence of temporal biodiversity change. We show a pervasive scale dependence of temporal trends in taxonomic (TD) and functional (FD) diversity for an ~50-year record of avian assemblages from North American Breeding Bird Survey and a record of global extinctions. Average TD and FD increased at all but the global scale. Change in TD exceeded change in FD toward large scales, signaling functional resilience. Assemblage temporal dissimilarity and turnover (replacement of species or functions) declined, while nestedness (tendency of assemblages to be subsets of one another) increased with scale. Patterns of FD change varied strongly among diet and foraging guilds. We suggest that monitoring, policy, and conservation require a scale-explicit framework to account for the pervasive effect that scale has on perceived biodiversity change.

    

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3. Bryophytes in fir waves: Forest canopy indicator species and functional diversity decline in canopy gaps

   https://doi.org/10.1111/jvs.12718  

   Berdugo, Monica B. ; Dovciak, Martin ; Nakashizuka, ed., Tohru ( March 2019 , Journal of Vegetation Science)

   Bryophytes can cover three quarters of the ground surface, play key ecological functions, and increase biodiversity in mesic high‐elevation conifer forests of the temperate zone. Forest gaps affect species coexistence (and ecosystem functions) as suggested by the gap and gap‐size partitioning hypotheses (GPH,G_SPH). Here we test these hypotheses in the context of high‐elevation forest bryophyte communities and their functional attributes.

   Spruce–fir forests on Whiteface Mountain, NY,USA.

   We characterized canopy openness, microclimate, forest floor substrates, vascular vegetation cover, and moss layer (cover, common species, and functional attributes) in three canopy openness environments (gap, gap edge, forest canopy) across 20 gaps (fir waves) (n = 60); the functional attributes were based on 16 morphologic, reproductive, and ecological bryophyte plant functional traits (PFTs). We testedGPHandG_SPHrelative to bryophyte community metrics (cover, composition), traits, and trait functional sensitivity (functional dispersion;FDis) using indicator species analysis, ordination, and regression.

   Canopy openness drove gradients in ground‐level temperature, substrate abundance and heterogeneity (beta diversity), and understory vascular vegetation cover. TheGPHwas consistent with (a) the abundance patterns of forest canopy indicator species (Dicranum fuscescens,Hypnum imponens, andTetraphis pellucida), and (b)FDisbased on threePFTs (growth form, fertility, and acidity), both increasing with canopy cover. We did not find support forGPHin the remaining species or traits, or forG_SPHin general; gap width (12–44 m) was not related to environmental or bryophyte community gradients.

   The observed lack of variation in most bryophyte metrics across canopy environments suggests high resistance of the bryophyte layer to natural canopy gaps in high‐elevation forests. However, responses of forest canopy indicator species suggest that canopy mortality, potentially increased by changing climate or insect pests, may cause declines in some forest canopy species and consequently in the functional diversity of bryophyte communities.

    

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4. Community Response to Extreme Drought ( CRED ): a framework for drought‐induced shifts in plant–plant interactions

   https://doi.org/10.1111/nph.15595  

   Ploughe, Laura W. ; Jacobs, Elin M. ; Frank, Graham S. ; Greenler, Skye M. ; Smith, Melinda D. ; Dukes, Jeffrey S. ( January 2019 , New Phytologist)

   Contents
   	Summary	52
   I.	Introduction	52
   II.	The Community Response to Extreme Drought (CRED) framework	55
   III.	Post‐drought rewetting rates: system and community recovery	61
   IV.	Site‐specific characteristics influencing community resistance and resilience	63
   V.	Conclusions	64
   	Acknowledgements	65
   	References	66

   As climate changes, many regions of the world are projected to experience more intense droughts, which can drive changes in plant community composition through a variety of mechanisms. During drought, community composition can respond directly to resource limitation, but biotic interactions modify the availability of these resources. Here, we develop the Community Response to Extreme Drought framework (CRED), which organizes the temporal progression of mechanisms and plant–plant interactions that may lead to community changes during and after a drought. TheCREDframework applies some principles of the stress gradient hypothesis (SGH), which proposes that the balance between competition and facilitation changes with increasing stress. TheCREDframework suggests that net biotic interactions (NBI), the relative frequency and intensity of facilitative (+) and competitive (−) interactions between plants, will change temporally, becoming more positive under increasing drought stress and more negative as drought stress decreases. Furthermore, we suggest that rewetting rates affect the rate of resource amelioration, specifically water and nitrogen, altering productivity responses and the intensity and importance ofNBI, all of which will influence drought‐induced compositional changes. System‐specific variables and the intensity of drought influence the strength of these interactions, and ultimately the system's resistance and resilience to drought.

    

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5. Gonadotrophin‐inhibitory hormone and its mammalian orthologue RF amide‐related peptide‐3: Discovery and functional implications for reproduction and stress

   https://doi.org/10.1111/jne.12597  

   Kriegsfeld, L. J. ; Jennings, K. J. ; Bentley, G. E. ; Tsutsui, K. ( July 2018 , Journal of Neuroendocrinology)

   At the turn of the millennium, a neuropeptide with pronounced inhibitory actions on avian pituitary gonadotrophin secretion was identified and named gonadotrophin‐inhibitory hormone (GnIH). Across bird species, GnIHacts at the level of the pituitary and the gonadotrophin‐releasing hormone (GnRH) neuronal system to inhibit reproduction. Subsequent to this initial discovery, orthologues of GnIHhave been identified and characterised across a broad range of species. In many vertebrates, the actions of GnIHand its orthologues serve functional roles analogous to those seen in birds. In other cases, GnIHand its orthologues exhibit more diverse actions dependent on sex, species, season and reproductive condition. The present review highlights the discovery and functional implications of GnIHacross species, focusing on research domains in which the significance of this neuropeptide has been explored most.

    

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