1. |
- Luize, Bruno Garcia, et al.
(författare)
-
Geography and ecology shape the phylogenetic composition of Amazonian tree communities
- 2024
-
Ingår i: JOURNAL OF BIOGEOGRAPHY. - 0305-0270 .- 1365-2699. ; 51:7, s. 1163-1184
-
Tidskriftsartikel (refereegranskat)abstract
- Aim: Amazonia hosts more tree species from numerous evolutionary lineages, both young and ancient, than any other biogeographic region. Previous studies have shown that tree lineages colonized multiple edaphic environments and dispersed widely across Amazonia, leading to a hypothesis, which we test, that lineages should not be strongly associated with either geographic regions or edaphic forest types. Location: Amazonia. Taxon: Angiosperms (Magnoliids; Monocots; Eudicots). Methods: Data for the abundance of 5082 tree species in 1989 plots were combined with a mega-phylogeny. We applied evolutionary ordination to assess how phylogenetic composition varies across Amazonia. We used variation partitioning and Moran's eigenvector maps (MEM) to test and quantify the separate and joint contributions of spatial and environmental variables to explain the phylogenetic composition of plots. We tested the indicator value of lineages for geographic regions and edaphic forest types and mapped associations onto the phylogeny. Results: In the terra firme and v & aacute;rzea forest types, the phylogenetic composition varies by geographic region, but the igap & oacute; and white-sand forest types retain a unique evolutionary signature regardless of region. Overall, we find that soil chemistry, climate and topography explain 24% of the variation in phylogenetic composition, with 79% of that variation being spatially structured (R-2 = 19% overall for combined spatial/environmental effects). The phylogenetic composition also shows substantial spatial patterns not related to the environmental variables we quantified (R-2 = 28%). A greater number of lineages were significant indicators of geographic regions than forest types. Main Conclusion: Numerous tree lineages, including some ancient ones (>66 Ma), show strong associations with geographic regions and edaphic forest types of Amazonia. This shows that specialization in specific edaphic environments has played a long-standing role in the evolutionary assembly of Amazonian forests. Furthermore, many lineages, even those that have dispersed across Amazonia, dominate within a specific region, likely because of phylogenetically conserved niches for environmental conditions that are prevalent within regions.
|
|
2. |
- ter Steege, Hans, et al.
(författare)
-
Mapping density, diversity and species-richness of the Amazon tree flora
- 2023
-
Ingår i: COMMUNICATIONS BIOLOGY. - 2399-3642. ; 6:1
-
Tidskriftsartikel (refereegranskat)abstract
- Using 2.046 botanically-inventoried tree plots across the largest tropical forest on Earth, we mapped tree species-diversity and tree species-richness at 0.1-degree resolution, and investigated drivers for diversity and richness. Using only location, stratified by forest type, as predictor, our spatial model, to the best of our knowledge, provides the most accurate map of tree diversity in Amazonia to date, explaining approximately 70% of the tree diversity and species-richness. Large soil-forest combinations determine a significant percentage of the variation in tree species-richness and tree alpha-diversity in Amazonian forest-plots. We suggest that the size and fragmentation of these systems drive their large-scale diversity patterns and hence local diversity. A model not using location but cumulative water deficit, tree density, and temperature seasonality explains 47% of the tree species-richness in the terra-firme forest in Amazonia. Over large areas across Amazonia, residuals of this relationship are small and poorly spatially structured, suggesting that much of the residual variation may be local. The Guyana Shield area has consistently negative residuals, showing that this area has lower tree species-richness than expected by our models. We provide extensive plot meta-data, including tree density, tree alpha-diversity and tree species-richness results and gridded maps at 0.1-degree resolution. A study mapping the tree species richness in Amazonian forests shows that soil type exerts a strong effect on species richness, probably caused by the areas of these forest types. Cumulative water deficit, tree density and temperature seasonality affect species richness at a regional scale.
|
|
3. |
- Beal, Jacob, et al.
(författare)
-
Robust estimation of bacterial cell count from optical density
- 2020
-
Ingår i: Communications Biology. - : Springer Science and Business Media LLC. - 2399-3642. ; 3:1
-
Tidskriftsartikel (refereegranskat)abstract
- Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data.
|
|
4. |
|
|
5. |
-
- 2019
-
Tidskriftsartikel (refereegranskat)
|
|
6. |
|
|
7. |
-
The Seventeenth Data Release of the Sloan Digital Sky Surveys : Complete Release of MaNGA, MaStar, and APOGEE-2 Data
- 2022
-
Ingår i: Astrophysical Journal Supplement Series. - : Institute of Physics (IOP). - 0067-0049 .- 1538-4365. ; 259:2
-
Tidskriftsartikel (refereegranskat)abstract
- This paper documents the seventeenth data release (DR17) from the Sloan Digital Sky Surveys; the fifth and final release from the fourth phase (SDSS-IV). DR17 contains the complete release of the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey, which reached its goal of surveying over 10,000 nearby galaxies. The complete release of the MaNGA Stellar Library accompanies this data, providing observations of almost 30,000 stars through the MaNGA instrument during bright time. DR17 also contains the complete release of the Apache Point Observatory Galactic Evolution Experiment 2 survey that publicly releases infrared spectra of over 650,000 stars. The main sample from the Extended Baryon Oscillation Spectroscopic Survey (eBOSS), as well as the subsurvey Time Domain Spectroscopic Survey data were fully released in DR16. New single-fiber optical spectroscopy released in DR17 is from the SPectroscipic IDentification of ERosita Survey subsurvey and the eBOSS-RM program. Along with the primary data sets, DR17 includes 25 new or updated value-added catalogs. This paper concludes the release of SDSS-IV survey data. SDSS continues into its fifth phase with observations already underway for the Milky Way Mapper, Local Volume Mapper, and Black Hole Mapper surveys.
|
|
8. |
- Caraccioli, Mauro J., et al.
(författare)
-
Forum : Interlingual relations: Approaches, conflicts, and lessons in the translation of global politics
- 2021
-
Ingår i: International Studies Review. - : Oxford University Press (OUP). - 1521-9488 .- 1468-2486. ; 23:3, s. 1015-1045
-
Forskningsöversikt (refereegranskat)abstract
- At stake in this forum are the politics of translation in the study of global politics. More specifically, the following interventions aim to consider the ways that scholars can recenter the utility of language toward more flexible conceptions of relationality. As each contribution reveals, translation is indispensable to individual theorizations of international politics; yet taken together, the forum aims to mitigate the alleged necessity of a lingua franca in IR scholarship. We go beyond the linguistic demands of conventional conceptual history in that each intervention employs a reflexive disposition to consider both their subject position and normative aspirations in the experience of translation. The forum's overall goal is to illustrate the ethical imperative to acknowledge the contextual specificity of linguistic encounters-past, present, and future-and in the process breathe life into the prose of world politics.
|
|
9. |
- Herborth, Benjamin, et al.
(författare)
-
Europe in Historical International Relations
- 2021
-
Ingår i: Routledge Handbook of Historical International Relations. - 9780815347644 - 9781351168960 ; , s. 432-440
-
Bokkapitel (refereegranskat)abstract
- Almost any conversation about Historical International Relations (IR) appears to be, at least implicitly, always already about Europe. The geographical and intellectual centrality of Europe shapes the way in which historically oriented work in IR operates. Paradoxically, despite a long and powerful lineage of disciplinary Eurocentrism, Europe has only rarely emerged as a conceptual focal point of historical investigation. Quite the contrary, its presence appears to go without saying. This chapter locates the reason for this in a teleological theory of history implicitly invoked with the articulation of Europe. We excavate how this implicit theory of history organizes debates in the English School tradition, in Historical Sociology, and in European Integration Theory thereby producing Europe as vanguard and telos of world history. In this way, we demonstrate that the centrality of Europe for Historical IR is not a matter of empirical focus but more fundamentally a question of conceptual and epistemological presuppositions. By addressing such conceptual Eurocentrism, we suggest, the horizon of possibility for historical and political engagements with Europe can be significantly expanded.
|
|
10. |
- Kustermans, Jorg, et al.
(författare)
-
Ritual and Authority in World Politics
- 2022
-
Ingår i: Cambridge Review of International Affairs. - : Informa UK Limited. - 0955-7571 .- 1474-449X. ; 35:1, s. 2-30
-
Tidskriftsartikel (refereegranskat)abstract
- The contributions to this Forum on Ritual and Authority in World Politics examine the role that ritual performances play in the constitution of positions of authority and the maintenance of relations of authority in historical and contemporary international relations. The Forum takes as its point of departure three related observations: (i) that recent years have witnessed a remarkable upsurge of interest in ritual as a recurring feature of international practice, but (ii) that this recent interest in ritual has not extended, thus far, to the study of international authority, (iii) in spite of political anthropologists’ long-standing claim that the performance of ritual is absolutely crucial to the production of authority. The performance of ritual grounds, makes tangible and enhances various forms of authority, including forms of international authority, historical and contemporary. The contributions to this Forum demonstrate the veracity of that claim in five different empirical contexts—Byzantine diplomacy, early modern cross-cultural encounters, British imperialism in India, military lawyering in America’s armed forces, and the casting of ballots in Crimea and the US—and attempt also to explain precisely how it is that ritual served to undergird and stabilise authority in these various instances.
|
|