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opencc-zeroApr 2024View details →

Data from: Evolutionary radiation strategy revealed in the Scarabaeidae with evidence of continuous spatiotemporal morphology and phylogenesis

Evolutionary biology faces the important challenge of determining how to interpret the relationship between selection pressures and evolutionary radiation. The lack of morphological evidence on cross-species research adds to difficulty of this challenge. We proposed a new paradigm for evaluating the evolution of branches through changes in characters on continuous spatiotemporal scales, for better interpreting the impact of biotic/abiotic drivers on the evolutionary radiation. It reveals a causal link between morphological changes and selective pressures: consistent deformation signals for all tested characters on timeline, which provided strong support for the evolutionary hypothesis of relationship between scarabs and biotic/abiotic drivers; the evolutionary strategies under niche differentiation, which were manifested in the responsiveness degree of functional morphological characters with different selection pressure. This morphological information-driven integrative approach sheds light on the mechanism of macroevolution under different selection pressures and is applicable to more biodiversity research.

opencc-zeroJul 2023View details →

Genetic and morphological data from two bird genera (Cranioleuca and Geospiza) showing continuous variation

Extinction is a dominant force shaping patterns of biodiversity through time however its role as a catalyst of speciation has been overlooked. Here, we synthesize ideas alluded to by Darwin and others into the model of 'speciation-by-extinction' in which speciation results from the extinction of intermediate populations within a single geographically variable species. We explore the properties and distinguishing features of speciation-by-extinction with respect to other established speciation models. We demonstrate its plausibility by showing that the experimental extinction of populations within variable species can result in speciation. The prerequisites for speciation-by-extinction, geographically structured intraspecific variation and local extinction, are ubiquitous in nature, indicating that speciation-by-extinction may be a prevalent, but underappreciated, speciation mechanism.

publicJul 2023View details →

Genetic and morphological data from two bird genera (Cranioleuca and Geospiza) showing continuous variation

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publicApr 2024View details →

Data from: Evolutionary radiation strategy revealed in the Scarabaeidae with evidence of continuous spatiotemporal morphology and phylogenesis

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zenodo32/100

Distribution. Extent of this species' distribution is not yet known; recorded with certainty in Morocco, Senegal, Saudi Arabia, and Yemen. It is thought to be continuously distributed from Mauritania and Senegal E to South Sudan, Ethiopia, and Eritrea. However, boundary between this species and the morphologically identical H. coffer is not known in Hipposideridae

Distribution. Extent of this species' distribution is not yet known; recorded with certainty in Morocco, Senegal, Saudi Arabia, and Yemen. It is thought to be continuously distributed from Mauritania and Senegal E to South Sudan, Ethiopia, and Eritrea. However, boundary between this species and the morphologically identical H. coffer is not known

opennotspecifiedOct 2019View details →

ClinicalTrials.gov32/100

Noninvasive Continuous BP Monitoring in Newborns Based on Pulsatile Signal Morphological Features Using NIRS

ClinicalTrials.gov study NCT06994494. IPD Sharing: YES. Countries: 1. Publications: 15.

controlledIPD-YESFeb 2026View details →

dryad28/100

Data from: Use of continuous traits can improve morphological phylogenetics

The recent surge in enthusiasm for simultaneously inferring relationships from extinct and extant species has reinvigorated interest in statistical approaches for modelling morphological evolution. Current statistical methods use the Mk model to describe substitutions between discrete character states. Although representing a significant step forward, the Mk model presents challenges in biological interpretation, and its adequacy in modelling morphological evolution has not been well explored. Another major hurdle in morphological phylogenetics concerns the process of character coding of discrete characters. The often subjective nature of discrete character coding can generate discordant results that are rooted in individual researchers' subjective interpretations. Employing continuous measurements to infer phylogenies may alleviate some of these issues. Although not widely used in the inference of topology, models describing the evolution of continuous characters have been well examined, and their statistical behaviour is well understood. Also, continuous measurements avoid the substantial ambiguity often associated with the assignment of discrete characters to states. I present a set of simulations to determine whether use of continuous characters is a feasible alternative or supplement to discrete characters for inferring phylogeny. I compare relative reconstruction accuracy by inferring phylogenies from simulated continuous and discrete characters. These tests demonstrate significant promise for continuous traits by demonstrating their higher overall accuracy as compared to reconstruction from discrete characters under Mk when simulated under unbounded Brownian motion, and equal performance when simulated under an Ornstein-Uhlenbeck model. Continuous characters also perform reasonably well in the presence of covariance between sites. I argue that inferring phylogenies directly from continuous traits may be benefit efforts to maximise phylogenetic information in morphological datasets by preserving larger variation in state space compared to many discretisation schemes. I also suggest that the use of continuous trait models in phylogenetic reconstruction may alleviate potential concerns of discrete character model adequacy, while identifying areas that require further study in this area. This study provides an initial controlled demonstration of the efficacy of continuous characters in phylogenetic inference.

opencc-zeroDec 2016View details →

dryad28/100

Data from: A continuous morphological approach to study the evolution of pollen in a phylogenetic context: an example with the order Myrtales

The study of pollen morphology has historically allowed evolutionary biologists to assess phylogenetic relationships among Angiosperms, as well as to better understand the fossil record. During this process, pollen has mainly been studied by discretizing some of its main characteristics such as size, shape, and exine ornamentation. One large plant clade in which pollen has been used this way for phylogenetic inference and character mapping is the order Myrtales, composed by the small families Alzateaceae, Crypteroniaceae, and Penaeaceae (collectively the "CAP clade"), as well as the large families Combretaceae, Lythraceae, Melastomataceae, Myrtaceae, Onagraceae and Vochysiaceae. In this study, we present a novel way to study pollen evolution by using quantitative size and shape variables. We use morphometric and morphospace methods to evaluate pollen change in the order Myrtales using a time-calibrated, supermatrix phylogeny. We then test for conservatism, divergence, and morphological convergence of pollen and for correlation between the latitudinal gradient and pollen size and shape. To obtain an estimate of shape, Myrtales pollen images were extracted from the literature, and their outlines analyzed using elliptic Fourier methods. Shape and size variables were then analyzed in a phylogenetic framework under an Ornstein-Uhlenbeck process to test for shifts in size and shape during the evolutionary history of Myrtales. Few shifts in Myrtales pollen morphology were found which indicates morphological conservatism. Heterocolpate, small pollen is ancestral with largest pollen in Onagraceae. Convergent shifts in shape but not size occurred in Myrtaceae and Onagraceae and are correlated to shifts in latitude and biogeography. A quantitative approach was applied for the first time to examine pollen evolution across a large time scale. Using phylogenetic based morphometrics and an OU process, hypotheses of pollen size and shape were tested across Myrtales. Convergent pollen shifts and position in the latitudinal gradient support the selective role of harmomegathy, the mechanism by which pollen grains accommodate their volume in response to water loss.

opencc-zeroDec 2016View details →

Figure 3 from: Morales EA, Wetzel CE, Ector L (2021) New and poorly known araphid diatom species (Bacillariophyta) from regions near Lake Titicaca, South America and a discussion on the continued use of morphological characters in araphid diatom taxonomy. PhytoKeys 187: 23-70. https://doi.org/10.3897/phytokeys.187.73338

Figure 3 A–F SEM micrographs of Pseudostaurosira pulchra sp. nov. from the Bolivian Altiplano A, B outer views of valves showing axial area, striae and spines features C inner view of valve still attached to neighboring cell. Black arrow indicates absence of apical pore field. Dotted arrow points to depression into which the stria opens internally D tilted view of frustule. Notice larger valvocopula, lateral growth of spines and blister-like depositions on abvalvar edge of mantle E outer view of valve tip. Black arrow denotes absence of apical pore field. Notice round to elliptical spine base and larger areola on valve mantle. F frustule attached to neighboring valve by means of heavily silicified spines. Notice open girdle elements (white arrow) and depositions along abvalvar mantle edge. Scale bars: 2 µm (E); 4 µm (C, F); 5 µm (A, B, D).

Figure 5 from: Morales EA, Wetzel CE, Ector L (2021) New and poorly known araphid diatom species (Bacillariophyta) from regions near Lake Titicaca, South America and a discussion on the continued use of morphological characters in araphid diatom taxonomy. PhytoKeys 187: 23-70. https://doi.org/10.3897/phytokeys.187.73338

Figure 5 A–F SEM images of Pseudostaurosira heteropolaris sp. nov. from the Bolivian Altiplano A, B Valve views showing striation pattern and features of the axial area, virgae, vimines, and spine location C side view of complete frustule and neighboring cell showing girdle bands (white arrows denote open copulae). White arrows point to open girdle elements D close up of C showing details of spines with bifurcations with pinnatifid projections, characteristics of the striae on valve mantle and the features of the blisters E broken frustule with girdle bands. Pattern of volae within areolae is also shown F frustule in side, tilted view. Notice open copulae (white arrow) and reduced apical pore field with cavernous poroids (black arrow). Scale bars: 1 µm (D); 3 µm (A–C, E); 4 µm (F).

Figure 2 from: Morales EA, Wetzel CE, Ector L (2021) New and poorly known araphid diatom species (Bacillariophyta) from regions near Lake Titicaca, South America and a discussion on the continued use of morphological characters in araphid diatom taxonomy. PhytoKeys 187: 23-70. https://doi.org/10.3897/phytokeys.187.73338

Figure 2 A–F SEM images of little known "araphid" diatoms from the Bolivian Altiplano A, BNanofrustulum cataractarumA specimen from the Desaguadero River, showing quasifract girdle elements with prominent ligulae (white arrows) B specimen from the Sajama River showing common internal depression into which the areolae open (dotted arrows) and the blister-like depositions of silica at the abvalvar edge of the mantle C, DN. rarissimum from the Desaguadero River C small, spineless valve D internal view showing apical and foot pole pore fields (black arrows) and internal depressions containing all areolae within a stria (dotted arrow) E, FPseudostaurosira sajamaensis from the Desaguadero River E top view showing gradual transition of valve face to mantle and the reduced apical pore fields (black arrow) F side view of two half cells still attached by heavily silicified spines. Notice open girdle elements (white arrows). Scale bars: 1 µm (B); 3 µm (C, E); 4 µm (A, D); 5 µm (F).

Figure 1 from: Morales EA, Wetzel CE, Ector L (2021) New and poorly known araphid diatom species (Bacillariophyta) from regions near Lake Titicaca, South America and a discussion on the continued use of morphological characters in araphid diatom taxonomy. PhytoKeys 187: 23-70. https://doi.org/10.3897/phytokeys.187.73338

Figure 1 A–M' LM images of little known and new "araphid" diatoms from the Bolivian Altiplano A–ENanofrustulum cataractarumF–LN. rarissimumM–SPseudostaurosira sajamaensisT–ZP. pulchra sp. nov. (Fig. 1U is the holotype) A'–G' P. aedes sp. nov. (Fig. 1A' is the holotype). H'–M' P. heteropolaris sp. nov. (Fig. 1I' is the holotype). Scale bar: 10 µm.

Figure 8 from: Morales EA, Wetzel CE, Ector L (2021) New and poorly known araphid diatom species (Bacillariophyta) from regions near Lake Titicaca, South America and a discussion on the continued use of morphological characters in araphid diatom taxonomy. PhytoKeys 187: 23-70. https://doi.org/10.3897/phytokeys.187.73338

Figure 8 A–F SEM images of Pseudostaurosira frankenae sp. nov. A, B titled frustules showing external features; notice open girdle elements in B (white arrows) C, D internal view of valves showing internal elliptic depositions on striae (dashed arrows) and depression of the apical pore field (black arrows) E close-up of frustule apex (B) showing the externally occluded apical pore field, showing only a single row of poroids (black arrow) F close-up of frustule tip (A) showing open girdle bands (white arrow). Scale bars: 2 µm (E, F); 3 µm (C); 5 µm (A, B, D).

Figure 10 from: Morales EA, Wetzel CE, Ector L (2021) New and poorly known araphid diatom species (Bacillariophyta) from regions near Lake Titicaca, South America and a discussion on the continued use of morphological characters in araphid diatom taxonomy. PhytoKeys 187: 23-70. https://doi.org/10.3897/phytokeys.187.73338

Figure 10 A–F SEM images of Pseudostaurosira oblonga sp. nov. A, B external views showing apical pore fields covered with small flaps (black arrow in A) and other characteristics C, E internal valve features stressing on apical pore fields and striae in a depression (black arrows in C and dashed arrow in C and E respectively) D, F titled views of valves showing girdle bands (white arrow in F) and apical pore field (black arrow in F). Scale bars: 4 µm (B, C, E, F); 5 µm (A, D).

Figure 4 from: Morales EA, Wetzel CE, Ector L (2021) New and poorly known araphid diatom species (Bacillariophyta) from regions near Lake Titicaca, South America and a discussion on the continued use of morphological characters in araphid diatom taxonomy. PhytoKeys 187: 23-70. https://doi.org/10.3897/phytokeys.187.73338

Figure 4 A–F SEM images of Pseudostaurosira aedes sp. nov. from the Bolivian Altiplano A top, tilted view of valve showing axial area, slightly raised virga, valve face areolae covered with bilobed or disk-like flaps, and slightly larger valve mantle areola covered with two or more flaps B, D, E, F girdle views showing features of the valve mantle, open girdle elements with larger valvocopula (white arrows in D and E). Notice serrate spines with well-developed stipules in F which have varying patterns C inner view showing reduced apical pore field (black arrow) and single depression into which the areolae open internally (dotted arrow). Scale bars: 4 µm (D); 5 µm (A–C, E, F).

Figure 7 from: Morales EA, Wetzel CE, Ector L (2021) New and poorly known araphid diatom species (Bacillariophyta) from regions near Lake Titicaca, South America and a discussion on the continued use of morphological characters in araphid diatom taxonomy. PhytoKeys 187: 23-70. https://doi.org/10.3897/phytokeys.187.73338

Figure 7 A–F SEM images of Pseudostaurosira vulpina sp. nov. A, B valve views showing striation pattern, features of the axial area, spine position and presence of depressed apical pore fields (black arrows) C, D close-ups with details of apical pore fields areolae and spines E tilted view of a frustule showing open girdle bands with overlapping extremes (white arrows) F internal view showing apical pore fields and the internal disk-like areolar depositions. Scale bars: 2 µm (C, D); 5 µm (A, B, E, F).

Figure 9 from: Morales EA, Wetzel CE, Ector L (2021) New and poorly known araphid diatom species (Bacillariophyta) from regions near Lake Titicaca, South America and a discussion on the continued use of morphological characters in araphid diatom taxonomy. PhytoKeys 187: 23-70. https://doi.org/10.3897/phytokeys.187.73338

Figure 9 A–F SEM images of Pseudostaurosira occulta sp. nov. A, B external views of valves showing apical pore fields (black arrow in A) and other features C internal view of valve showing depressions containing the striae (dashed arrow) D internal close-up showing apical pore field depression (black arrow) and striae depression (dashed line) E close-up on valve apex showing flaps on apical pore field (black arrow) and open girdle element (white arrow) F close-up on cell-cell connection showing apical pore field covered with flaps (black arrow) and open girdle element (white arrow). Scale bars: 2 µm (D, E); 3 µm (F); 5 µm (A–C).

Figure 6 from: Morales EA, Wetzel CE, Ector L (2021) New and poorly known araphid diatom species (Bacillariophyta) from regions near Lake Titicaca, South America and a discussion on the continued use of morphological characters in araphid diatom taxonomy. PhytoKeys 187: 23-70. https://doi.org/10.3897/phytokeys.187.73338

Figure 6 A–V LM images of little known and new "araphid" diatoms from the Bolivian Altiplano A–DPseudostaurosira vulpina stat. nov. E–IP. frankenae sp. nov. (Fig. 6E is the holotype) J–OP. occulta sp. nov. (Fig. 6K corresponds to the holotype) P–VP. oblonga sp. nov. (Fig. 6R corresponds to the holotype). Scale bar: 10 µm.