Geometric morphometrics analysis (GMA) is a well-known technique to identify minute changes in Drosophila wings. This study aimed to determine potential changes in Drosophila wings shape and size ...after exposure to polystyrene nanoplastics (NPs) (50 nm) and microplastics (MPs) (1 μm). Flies were exposed from eggs to pupal eclosion and analyzed using GMA. Results revealed a difference in shape and size between male and female wings, as expected, due to sexual dimorphism. Therefore, wings were analyzed by sex. Wings of MPs and NPs treated females were elongated compared to controls and had a constriction of the wing joint. Additionally, MPs treated female flies had the most dissimilar shape compared to controls. In male flies, NPs flies had smaller wings compared to MPs and control flies. Compared to control, NPs wings of males were shrunken at the joint and in the entire proximal region of the wing. However, male MPs wings had a narrower anal region and were slightly elongated. These results reveal that wing shape and size can change in a different way based on the sex of the flies and size of plastic particles that larvae interacted with. All the changes in the wings occurred only within the normally allowed wing variation and treatment with NPs/MPs did not cause development of the aberrant phenotypes. Results can pave the way for further understanding of how MPs and NPs can alter phenotypes of flies.
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•Flies fed with micro/nanoplastic were analyzed by geometric morphometrics analysis.•Female wings were elongated compared to control and had a wing joint constriction.•Male flies fed with nanoplastic had smaller wings compared to control flies.•Male wings were shrunken at the joint and in the entire proximal region of the wing.•Wing shape/size vary depending on the size of plastic particles consumed by larvae.
Geometric morphometric (GM) tools are essential for meaningfully quantifying and understanding patterns of variation in complex traits like shape. In this field, the breadth of answerable questions ...has grown dramatically in recent years through the development of new analyses and increased computational efficiency.
In this note, we describe the ways in which geomorph, a widely used R package for quantifying and analysing GM data, has grown with the field.
We present geomorph v4.0 and describe the ways in which this version has dramatically improved upon previous versions. We also present a new graphical user interface for easy implementation, gmShiny.
These contributions position geomorph to be the primary tool for GM analyses, particularly those employing a phylogenetic comparative approach.
Genital structures are among the most variable in nature and have been suggested to evolve at exceptionally high rates. However, the vast majority of research on genital morphology has been done on ...male genitalia. We present one of the few studies of female genital shape using geometric morphometrics, and the first of such studies to employ 3D geometric morphometrics, using the spiny dogfish shark, a taxon for which reproductive biology is well‐studied. In a sample of 21 adult females, we found no correlation between body size and reproductive and non‐reproductive trait size, and therefore no general allometric patterns. Furthermore, we found limited evidence for different 2D and 3D vaginal shapes in visibly pregnant and not visibly pregnant sharks, but trends were more obvious in 3D than 2D. We found high congruence between data derived using 2D geometric morphometrics with that derived from 3D methods. We also found exceptionally high asymmetry in the vagina, again more apparent in 3D than in 2D. Visibly pregnant sharks had especially high directional asymmetry (>48% of total variation) likely as a result of an asymmetric distribution of pups in the shark's paired oviducts. Therefore, this asymmetry was functional rather than developmental and presents an important consideration when studying vaginal shape. The lack of significant association between pregnancy and vaginal shape in a species with an extremely long pregnancy suggests that vaginal shape differences may be under additional selective forces such as sexual antagonism during copulation. A combination of 3D geometric morphometric methods along with assessments of asymmetry sheds further light on the growing appreciation that female genitalia is highly variable in shape and may play a substantial role in sexual selection.
Female genital shape is highly variable, but this variability has only been recently appreciated. We analyzed the female genital shape of the spiny dogfish shark using a combination of traditional linear measurements and 2D and 3D geometric morphometrics to understand whether pregnancy affects vagina shape. We found limited evidence based on our sample that pregnancy affects vagina shape with 3D geometric morphometrics separating sharks somewhat better than 2D. We did find significant asymmetry in the vagina such that visibly pregnant sharks had 48% of their total shape variation summarized by directional asymmetry alone. This is likely due to the asymmetric distribution of pups in the shark's paired oviducts. Such high levels of asymmetry are an important factor to consider when analyzing vaginal shape. Due to the lack of a significant relationship between pregnancy and vaginal shape, we suggest the spiny dogfish vagina is under selective forces in addition to pregnancy.
‘New glume wheat’ (NGW) is an archaeobotanical type increasingly recognised at Neolithic–Bronze Age sites across Europe and Western Asia. NGW has been recognised via aDNA and morphological analyses ...of chaff remains as a member of the Triticum timopheevii wheat group, recent cultivation of which is known only from western Georgia. This study combines geometric morphometric (GMM) analysis of NGW grains with updated results from a parallel study of chaff dehiscence, to assess the taxonomic classification and domestication status of NGW from the Neolithic East Mound at Çatalhöyük (central Anatolia).
Results confirm close comparability of NGW with modern wheats from the group T. timopheevii, in a form which has remained remarkably similar over thousands of years. Furthermore, the analysis suggests that NGW was undergoing selection for domestication traits in terms of shattering behaviour and grain form during the 1150-year East Mound sequence. These findings are interpreted in the context of substantial archaeobotanical evidence for a broad-spectrum plant strategy at Çatalhöyük which mitigated the risk of resource failure and supported experimentation in cropping. Possible cultural and practical incentives are considered for investment in the crop, made despite the availability of a fully-domesticated glume wheat (emmer) with similar growing and processing requirements. Alongside this, the study demonstrates the sensitivity of GMM to differences between and within wheat species, with methodological findings that can inform future studies.
•Geometric morphometrics can identify charred archaeological wheat grains to species.•Morphometrics reinforces link between archaeological remains and Timopheev's wheats.•Within glume wheat species, grain shape can be linked to domestication status.•Timopheev's wheat underwent selection for domestication traits at Çatalhöyük.
•Schizophrenia and bipolar disorders are associated with subtle facial shape differences.•Geometric morphometrics reveals sex-specific facial patterns in psychotic disorders.•Face and brain combined ...data emerge as potential biomarkers for psychotic disorders.
Given the shared ectodermal origin and integrated development of the face and the brain, facial biomarkers emerge as potential candidates to assess vulnerability for disorders in which neurodevelopment is compromised, such as schizophrenia (SZ) and bipolar disorder (BD).
The sample comprised 188 individuals (67 SZ patients, 46 BD patients and 75 healthy controls (HC)). Using a landmark-based approach on 3D facial reconstructions, we quantified global and local facial shape differences between SZ/BD patients and HC using geometric morphometrics. We also assessed correlations between facial and brain cortical measures. All analyses were performed separately by sex.
Diagnosis explained 4.1 % - 5.9 % of global facial shape variance in males and females with SZ, and 4.5 % - 4.1 % in BD. Regarding local facial shape, we detected 43.2 % of significantly different distances in males and 47.4 % in females with SZ as compared to HC, whereas in BD the percentages decreased to 35.8 % and 26.8 %, respectively. We detected that brain area and volume significantly explained 2.2 % and 2 % of facial shape variance in the male SZ - HC sample.
Our results support facial shape as a neurodevelopmental marker for SZ and BD and reveal sex-specific pathophysiological mechanisms modulating the interplay between the brain and the face.
A new, three‐dimensional geometric morphometric approach was assessed to study the effect of developmental temperature on fish heart shape utilizing geometric morphometrics of three‐dimensional ...landmarks captured on digitally reconstructed zebrafish hearts. This study reports the first three‐dimensional analysis of the fish heart and demonstrates significant shape modifications occurring after three developmental temperature treatments (TD = 24, 28 or 32°C) at two distinct developmental stages (juvenile and adult fish). Elevation of TD induced ventricle roundness in juveniles, males and females. Furthermore, significant differences that have not been described so far in heart morphometric indices (i.e., ventricle sphericity, bulbus arteriosus elongation and relative location, heart asymmetry) were identified. Sex proved to be a significant regulating factor of heart shape plasticity in response to TD. This methodology offers unique benefits by providing a more precise representation of heart shape changes in response to developmental temperature that are otherwise not discernable with the previously described two‐dimensional methods. Our work provides the first evidence of three‐dimensional shape alterations of the zebrafish heart adding to the emerging rationale of temperature‐driven plastic responses of global warming and seasonal temperature disturbances in wild fish populations and in other ectothermic vertebrates as well (amphibians and reptiles).
We examined the effect of developmental temperature on the three‐dimensional heart shape of zebrafish. We found that temperature experienced during the embryonic and larval stages permanently alters ventricle sphericity and other significant heart morphometric indices in juvenile, male and female fish that have not been described so far.
The effect of microplastics (MP) exposure on the chironomid species Chironomus riparius Meigen, 1804 was investigated using the OECD sediment and water toxicity test. Chironomid larvae were exposed ...to an environmentally relevant low microplastics concentration (LC), a high microplastics concentration (HC) and a control (C). The LC was 0.007 g m−2 on the water surface + 2 g m−3 in the water column + 8 g m−2 in the sediment, and the HC was 10 X higher than this for each exposure. The size of the majority of the manufactured microplastic pellets varied between 20 and 100 μm. The MP mixture consisted of: polyethylene-terephtalate (PET), polystyrene (PS), polyvinyl-chloride (PVC) and polyamide (PA) in a ratio of 45%: 15%: 20%: 20%, respectively, for the sediment exposure; 100% polyethylene for the water column exposure; and 50% polyethylene: 50% polypropylene for the water surface exposure. Different endpoints were monitored, including morphological changes in the mandibles and mentums of 4th instar larvae, morphological changes in the wings, mortality, emergence ratio, and developmental time. A geometric morphometric analysis showed a tendency toward widening of the wings, elongation of the mentums and changing the shape of the mandibles in specimens exposed to both concentrations of microplastics. The development time of C. riparius was significantly prolonged by the MP treatment: 13.8 ± 0.5; 14.4 ± 0.6; and 15.3 ± 0.4 days (mean ± SD) in the C, LC, and HC, respectively. This study indicates that even environmentally relevant concentrations of MP mixture have a negative influence on C. riparius, especially at the larval stage.
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•Exposure to a mixture of microplastics postponed developmental time of C. riparius.•The average body mass and average body length increased.•The right female wings showed differences in the wing shape in treatments.•The mouthparts deformities of the 4th instar larvae were observed in treatments.•Low concentration of MP mixture had negative influence on C. riparius.
Developmental time of C. riparius was prolonged in treatments. Mandibles showed a tendency to widen; the medium tooth and inner lateral teeth of mentums to shorten.
View on Scopus Lucilia cuprina and Lucilia sericata are two closely related species due to their similarity in morphology, habitat, distribution, and economic importance. Even though other methods ...have segregated the species, the aspect of comparative studies on geometric morphometrics and cuticular hydrocarbon composition in species variability is yet to be explored in these species. This study was conducted to assess variability between the two species and between the sexes. Wing shapes of 187 specimens of both species were analysed by geometric morphometric techniques. Landmarks 11, 10, 6 and 9, which corresponds to the intersection between the medial and the radial medial veins, medial and branched cubitus veins, distal end of radius vein (R2 + 3 vein) and curve point of medial vein, respectively, contributed significantly to the variability within and between species. Cuticular hydrocarbon profiles of four randomly collected individuals each of male and female L. cuprina and L. sericata, were assessed using GC-MS. Octadecene, Celidoniol, Hexatriacontane, Tetracontane and Tetracontane were identified as common for both species. 9-Octadecenal(z) and Tetracosane-11-decyl being recorded as the most abundant hydrocarbons in male and female L. cuprina, and 13-methylheptacosane and Tetratetracontane in male and female L. sericata, respectively. Diagnostic characters indicating the variabilities can be used for the identification of the species.
Masculine facial morphology (e.g., larger jaw, prominent cheekbones) have been linked to a suite of social outcomes—including greater wealth, career progress, romantic desirability, and even greater ...political success. A leading explanation for these links is that dominant facial structures represent honest cues of physical dominance and fighting ability. Třebický et al. (2013) published the first study to demonstrate that masculine facial cues (e.g., large nose, deep-set eyes) similarly predict both dominance judgments and real-world fighting success, but no studies have replicated these popular findings that a large and specific assortment of masculine facial structures are implicated in both fighting ability and dominance perception. Thus, we conducted a pre-registered direct replication and extension of Třebický et al. (2013). Two separate samples of United States MTurk participants rated 516 UFC fighters' facial photographs on perceived aggressiveness (N = 500) and fighting ability (N = 500). Results showed that perceived aggressiveness was associated with masculine facial morphology (e.g., large nose, deep-set eyes) independent of bodily size. There was also some evidence that perceived fighting ability was associated with masculine facial morphology, which disappeared after controlling for bodily size. There was no support for the relation between facial structure and fighting success, and there were often negative relations between perceived aggressiveness and fighting ability on fighting success (i.e., more successful fighters were perceived as less successful and aggressive). We argue that our evolved psychology differentially processes the distinct avenues to victory that constitute overall fighting success (e.g., knockout versus submission wins).
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