Morphological Plasticity Research Articles

Molecular Innovations Shaping Beak Morphology in Birds.

The beak, a pivotal evolutionary trait characterized by high morphological diversity and plasticity, has enabled birds to survive mass extinction events and subsequently radiate into diverse ecological niches worldwide. This remarkable ecological adaptability underscores the importance of uncovering the molecular mechanisms shaping avian beak morphology, particularly benefiting from the rapidly advancing archives of genomics and epigenomics. We review the latest advancements in understanding how genetic and epigenetic innovations control or regulate beak development and drive beak morphological adaptation and diversification over the past two decades. We conclude with several recommendations for future endeavors, expanding to more bird lineages, with a focus on beak shape and the lower beak, and conducting functional experiments. By directing research efforts toward these aspects and integrating advanced omics techniques, the complex molecular mechanisms involved in avian beak evolution and morphogenesis will be deeply interpreted.

The role of serum albumin in Candida albicans filamentation, germ tube formation, and farnesol sequestration.

Candida albicans is an opportunistic pathogen and colonizer of the human gut and mucosal membranes. C. albicans exhibits morphological plasticity, which is crucial for its fitness within the host and virulence. Morphogenesis in C. albicans is regulated, in part, by its production of farnesol, an autoregulatory molecule that inhibits filamentation. Morphogenesis is also regulated in response to external cues, such as serum, which stimulates hyphal formation by C. albicans. The precise mechanism by which serum stimulates hyphal formation is unknown. The most abundant serum protein is albumin. The binding affinity of albumin for nonpolar, fatty-acid-like molecules suggests that it may interact directly with exogenous farnesol and influence morphogenesis through sequestration of free farnesol. To test this hypothesis, we assessed whether albumin and albumin devoid of fatty acids (i) stimulated farnesol secretion and (ii) influenced the farnesol threshold required to inhibit filamentation. We found that albumin promoted farnesol secretion and filamentation, and the extent of its ability to do so was based on the presence or absence of bound fatty acids. We hypothesize that albumin not bound to fatty acids has the capacity to bind to farnesol and sequester it from C. albicans, encouraging filamentation.IMPORTANCEFor at least 50 years, researchers have wondered about the mechanisms by which serum stimulates germ tube formation (GTF) and hyphal growth in C. albicans. Here, we tested a model (Nickerson et al., Microbiol Mol Biol Rev 88:e00081-22, 2024, https://doi.org/10.1128/mmbr.00081-22) that serum promotes GTF and farnesol synthesis in part by extracting internal farnesol (Fi) from the cells toward the excess binding capacity of the albumins. The data presented here suggests that albumin not bound by fatty acids sequesters free farnesol thereby modulating filamentation and farnesol secretion by altering the equilibrium of internal vs external farnesol. We expect that the influence of secreted farnesol on cell morphology will differ during pathogenesis depending on location within the body, but sequestration of farnesol in the blood could mediate immune cell recruitment and promote hyphal formation.

Wave exposure influences kelp morphological and biomechanical phenotypic plasticity

Despite global and local declines in kelp ecosystems, luxuriant kelp beds persist at the Eastern Shore Islands (ESI) in Nova Scotia, Canada. Kelp beds in other regions of Nova Scotia were defoliated as the invasive bryozoan Membranipora membranacea and warming temperatures weakened kelp tissues and enhanced erosion and dislodgment. We propose that the high wave exposure at the ESI causes morphological and biomechanical phenotypic plasticity of kelp tissues. We compared differences in morphology and mechanical properties of the kelps Laminaria digitata and Saccharina latissima across 3 sites with different wave exposures, and differences in mechanical properties across blade lengths. Both species showed morphological plasticity; higher wave exposure resulted in longer and thicker stipes and thicker blades with increased branching. The mechanical properties of L. digitata showed increased breaking stress (strength) and strain (extensibility) with higher wave exposure, whereas S. latissima did not show mechanical plasticity with increasing exposure. For both species, blades were weaker but more extensible at the meristem and stronger but less extensible near the distal end of the blade. Larger and stronger kelp from high-exposure areas may promote the persistence of kelp beds in the ESI despite local stressors.

Synaptopodin: a key regulator of Hebbian plasticity

Synaptopodin, an actin-associated protein found in a subset of dendritic spines in telencephalic neurons, has been described to influence both functional and morphological plasticity under various plasticity paradigms. Synaptopodin is necessary and sufficient for the formation of the spine apparatus, stacks of smooth endoplasmic reticulum cisternae. The spine apparatus is a calcium store that locally regulates calcium dynamics in response to different patterns of activity and is also thought to be a site for local protein synthesis. Synaptopodin is present in ~30% of telencephalic large dendritic spines in vivo and in vitro highlighting the heterogeneous microanatomy and molecular architecture of dendritic spines, an important but not well understood aspect of neuroplasticity. In recent years, it has become increasingly clear that synaptopodin is a formidable regulator of multiple mechanisms essential for learning and memory. In fact, synaptopodin appears to be the decisive factor that determines whether plasticity can occur, acting as a key regulator for synaptic changes. In this review, we summarize the current understanding of synaptopodin’s role in various forms of Hebbian synaptic plasticity.

Growth conditions but not the variety, affect the yield, seed oil and meal protein of camelina under Mediterranean conditions

European agriculture policies emphasize the importance of agricultural sustainability, focusing on increase of biodiversity through crop diversification. In Mediterranean dryland cropping systems, the introduction of crops in rotation with cereals is challenged by scarce precipitation and high evapotranspiration. In this scenario, camelina (Camelina sativa (L.) Crantz), a low-input annual oleaginous crop with a high morphological plasticity, short life cycle, and interesting oil and meal composition, could be an option to be included in rotation with winter cereals. The aim of this experiment was to study the agronomic performance, and seed oil and meal protein contents of camelina in two different climatic conditions, with a sowing delay in one of them. Several trials were conducted in Montargull (Mediterranean semihumid) and in Lleida (Mediterranean semiarid) in two seasons (2020–21 and 2021–22). In Montargull, two sowing dates (November, SD1 and January, SD2) were established. In each growing condition, three spring camelina varieties were sown (Calena, CO46 and GP204). Camelina was harvested between May and July, and yield and harvest index were measured. After cold pressing the seeds, seed oil and meal protein contents were analysed. Camelina yield and quality was not related to the variety, but to two climatic scenarios: 1) a favourable rainfall distribution without important drought periods (2020–21); 2) significant rainfalls in November and April, but with a drought period in between (2021–22). In the first situation, camelina production ranged from 1533 to 2187 kg ha−1, with high seed oil (40.4–41.4 %) and meal protein (41.0–44.8 %) contents. In the second situation, the yield decreased to 242–661 kg ha−1, seed oil content to 31.0–34.7 %, and meal protein content to 37.6–40.4 %. Despite these seasonal differences, SD1 in Montargull obtained higher average yields and protein content than in Lleida and in SD2. In contrast, in Lleida and in SD2 in Montargull camelina produced higher oil content. The implementation of camelina into Mediterranean dryland crop rotation systems is feasible. Considering the importance of moisture in these climatic conditions, the use of no-till practices is recommended in dryland fields to avoid excessive water loss, while the use of camelina in irrigated fields could be explored. However, more long-term agronomic and industrial research is still needed.

A one-day journey to the suburbs: circadian clock in the Drosophila visual system.

Living organisms, which are constantly exposed to cyclical variations in their environment, need a high degree of plasticity in their visual system to respond to daily and seasonal fluctuations in lighting conditions. In Drosophila melanogaster, the visual system is a complex tissue comprising different photoreception structures that exhibit daily rhythms in gene expression, cell morphology, and synaptic plasticity, regulated by both the central and peripheral clocks. In this review, we briefly summarize the structure of the circadian clock and the visual system in Drosophila and comprehensively describe circadian oscillations in visual structures, from molecules to behaviors, which are fundamental for the fine-tuning of visual sensitivity. We also compare some features of the rhythmicity in the visual system with that of the central pacemaker and hypothesize about the differences in the regulatory signals and mechanisms that control these two clocks.

A strategy for improving the mechanical properties of silk fibers through the combination of genetic manipulation and zinc ion crosslinking

Silk fiber is generally considered an excellent biological material due to its good biocompatibility, morphological plasticity and biodegradability. Previously, the construction of silkworm silk gland bioreactors based on the piggyBac transposon has been optimized. However, the inserted exogenous genes have problems such as position uncertainty, and expression is not strictly controlled. Here, we applied transcription activator-like effector nuclease (TALEN)-mediated homology-directed repair (HDR) to precisely insert histidine-rich cuticular protein (CP) into silkworm Sericin1 (Ser1) gene. The Ser1-CP fusion protein was successfully secreted into cocoon shell. Subsequently, based on the metal coordination ability of the histidine imidazole group, we crosslinked cocoon with metal ions in vitro. In this strategy, the mechanical properties of the fused silk fibers with crosslinked Zn2+ improved, and the maximum breaking stress of the crosslinked Zn2+-fused silk fibers was 23.5 % greater than that of the wild-type fibers. Analysis of the secondary structure of the silk protein showed that the fused silk fibers crosslinked with Zn2+ had more β-sheet structures. This study pioneered a method of improving the mechanical properties of silk fibers by crosslinking metal ions with fused exogenous proteins and expanded the application value of silk gland bioreactors in the development of novel biomaterials.

Transcriptomic analysis reveals the mechanism underlying salinity-induced morphological changes in Skeletonema subsalsum.

Diatom cell walls are diverse and unique, providing the basis for species identification and supporting the ecological and economic value of diatoms. However, these important structures sometimes change in response to environmental fluctuations, especially under salt adaptation. Although studies have shown that salinity induces morphological plasticity changes in diatom cell walls, most research has focused on physiological responses rather than molecular mechanisms. In this study, Skeletonema subsalsum was cultured under four salinity conditions (0, 3, 6, 12). Through morphological and physiological methods, we found that salinity increased the cell diameter, protrusion lengths, distance between adjacent cells (DBCs), and nanopore size, while reducing cell height and silicification degree. To further investigate the mechanism underlying morphological changes in S. subsalsum, complementary transcriptome analysis was performed. In total, 20,138 differentially expressed genes (DEGs) were identified among the four treatments. Among them, 231 DEGs were screened and found to be closely associated with morphological changes, of which 107 were downregulated and 124 were upregulated. The findings demonstrated that elevated salinity inhibited silicon transport and deposition via downregulating the expression of DEGs involved in functions including chitin metabolism, putrescine metabolism, and vesicle transport, resulting in reduced silicon content and cell height. Increased salinity promoted the expression of DEGs related to microtubules (MTs), actin, and ubiquitin, which synchronously induced morphological changes. These findings provide a more comprehensive understanding of the salt tolerance of algae and a foundation for future studies on cell wall morphogenesis.

Naturalization of the Ornamental Plant Crocus tommasinianus Herb. (Iridaceae) in Forest Ecosystems: A Case Study from Poland

Highlights: Though not highly invasive, bulb and corm ornamental plants can escape cultivation and naturalize in new areas. Studying their naturalization is key to understanding their ecological impact and managing biodiversity. Objectives: This study aimed to document the first naturalization case of Crocus tommasinianus Herb. in Poland and assess the morphological variability of the naturalized population under different environmental conditions. Another objective was to identify diagnostic features in seed testa ornamentation to distinguish C. tommasinianus from related species (C. vernus (L.) Hill. and C. scepusiensis (Rehmann et Wol.) Borbás ex Kulcz.). Methods: The morphometric studies were performed within four subpopulations of C. tommasinianus differing in environmental conditions, determined with Ellenberg indices. Multivariate tests, ANOVA, and post-hoc tests were used to determine the morphometric diversity of specimens and to relate them to environmental factors. Seed micro-ornamentation was examined using a scanning electron microscope. Results: Light and temperature were negatively correlated, while moisture, soil pH, and nitrogen were positively correlated with many morphological traits. Plants spreading into forest ecosystems exhibited better-developed features (larger leaves and flowers) than those in former cultivation sites, indicating higher survival potential. The seed coat is papillate, with distinct differences in the shape, size, and secondary sculpture of the papillae compared to C. vernus and C. scepusiensis. Given that floristic studies often occur during the fruiting period of crocuses, testa ornamentation is crucial for identifying the studied species. Conclusions: The observed naturalization of C. tommasinianus demonstrates the high morphological plasticity of plants, which makes them capable of colonizing new areas, including forest habitats.

P01.08.A HYOXIA-INDUCED EXPRESSION OF ARHGAP FAMILY MEMBERS PROMOTES GLIOBLASTOMA DISSEMINATION

Abstract BACKGROUND The Rho GTPase activating proteins (ARHGAPs) perform vital roles in the regulation of the Rho GTPases with direct effect on cellular plasticity and cell migration/invasion. We recently reported on the role of five ARHGAPs, identified by a microarray screen, in morphological plasticity in established and patient-derived Glioblastoma (GBM) cell lines and associated clinical relevance in terms of tumour recurrence after treatment. We established that the ARHGAPs either promoted or targeted cell migration/invasion by allowing cells to undergo morphological changes in preparation for dissemination. We also showed that co-expression of two ARHGAPs, 12 and 29, is associated with reduced time to recurrence after initial treatment in patients. ARHGAP activity has been also reported in metastatic cancers including breast and colorectal cancer highlighting the biological relevance of these, as yet understudied, proteins. MATERIAL AND METHODS Here, we explored the GBM microenvironment and the effect of hypoxia on ARHGAP expression and localisation in glioma cell lines. RESULTS Using immunocytological and in vitro migration and invasion assays we were able to ascertain that ARHGAP4, 12, 22, 25 and 29 acquired subcellular distributions different to those recorded under normoxia and expression also decreased or increased under hypoxia. We also found that the effect of the migrastatic inhibitor 6-bromo-indirubin-3′-oxime (BIO) targeting GSK-3 signalling was potentiated when cells were challenged with the drug under hypoxic conditions. CONCLUSION Our results confirm our initial findings of biological relevance of the ARHGAPs in cellular activities and highlight important roles for the ARHGAPs for promoting migratory/invasive activity and behaviour in GBM cells. We also conclude that migrastatic inhibitors will exert enhanced activity on GBM cells under hypoxic conditions making them excellent candidates for complement treatment with cytotoxic drugs or radiotherapy for an improved management of GBM.

Concerted transcriptional regulation of the morphogenesis of hypothalamic neurons by ONECUT3

Acquisition of specialized cellular features is controlled by the ordered expression of transcription factors (TFs) along differentiation trajectories. Here, we find a member of the Onecut TF family, ONECUT3, expressed in postmitotic neurons that leave their Ascl1+/Onecut1/2+ proliferative domain in the vertebrate hypothalamus to instruct neuronal differentiation. We combined single-cell RNA-seq and gain-of-function experiments for gene network reconstruction to show that ONECUT3 affects the polarization and morphogenesis of both hypothalamic GABA-derived dopamine and thyrotropin-releasing hormone (TRH)+ glutamate neurons through neuron navigator-2 (NAV2). In vivo, siRNA-mediated knockdown of ONECUT3 in neonatal mice reduced NAV2 mRNA, as well as neurite complexity in Onecut3-containing neurons, while genetic deletion of Onecut3/ceh-48 in C. elegans impaired neurocircuit wiring, and sensory discrimination-based behaviors. Thus, ONECUT3, conserved across neuronal subtypes and many species, underpins the polarization and morphological plasticity of phenotypically distinct neurons that descend from a common pool of Ascl1+ progenitors in the hypothalamus.

Morphological and physiological plasticity of tomato in response to Azolla fern, a novel organic fertilizer of environmentally friendliness

Tomatoes are highly valued vegetable crops due to their excellent nutritional content. However, production remained low due to an incorrect combination of organic and inorganic soil nutrition. A pot experiment was conducted under shaded conditions with Azolla and inorganic nitrogen fertilization to determine the morphological and physiological plasticity of tomatoes. The study used a factorial combination of four levels of Azolla (0, 25, 50, and 75 g per pot) and four levels of nitrogen (0, 0.23, 0.46, and 0.69 g per pot) in a complete randomized design with three replications. We collected data on chlorophyll content (Chl a, Chl b, TChl), photosynthetic rate, water use efficiency, transpiration rate, stomata number, branch number (primary and secondary), plant height, leaf area, stomata conductance, relative water content, and number of leaves. Analysis of variance was employed to analyze the data, and the means were separated using the least significant differences test at a 5 % significance level. The results showed that primary and secondary branches, stomata number, transpiration rate, and water use efficiency were highly plastic due to the higher nitrogen levels and Azolla alone. The interaction effect of Azolla and nitrogen had a significant influence on chlorophyll content, photosynthesis rate, stomatal conductance, relative water content, number of leaves, plant height, and leaf area. It can be concluded that a balanced combination of organic and inorganic fertilizers remains essential for optimal tomato growth and physiology, emphasizing that the exclusive use of organic farming methods may not be the ideal solution.

Seasonal and circadian rhythms of clerodane diterpenes and glycosylated flavonoids in two varieties of Casearia sylvestris Sw. (Salicaceae)

Casearia sylvestris Sw. (Salicaceae) is noted for its morphological and chemical plasticity and pharmacological properties. The present study investigates two of its varieties: C. sylvestris var. sylvestris, predominant in dense and humid forests and ecotones and characterized by clerodane diterpenes; and C. sylvestris var. lingua, mainly found in xeric and open savannah areas and containing phenolic compounds. Despite their comprehensive chemical profiles, the dynamics of clerodane diterpenes and glycosylated flavonoids remain unknown. This study thus aimed to describe seasonal and circadian variations in their content in the leaves of the two varieties. The relative contents of five diterpenes and three glycosylated flavonoids were monitored monthly, every 3 h for 48 h, over 1 year via high-performance liquid chromatography coupled to diode array detection (HPLC-UV-DAD). The differential expression of photosynthetic proteins (Rubisco and photosystem II) was analyzed by Western blotting. The contents of both chemical classes decreased during the reproductive stage, though the prevalence of diterpenes in var. sylvestris and flavonoids in var. lingua remained unchanged; furthermore, even when the plants are grown under the same geographic and environmental conditions, Rubisco expression in var. lingua is twice that of var. sylvestris. In var. lingua, photosystem II proteins are 10% less expressed. The study reveals the circadian and seasonal fluctuations and, thus, prevalence of the two main compound classes in the examined varieties. The expression of the investigated photosynthetic proteins provides insights into the two varieties, supporting the prevalence of var. lingua in Cerrado areas and var. sylvestris in Atlantic Forest areas.

Effects of structural remodelling on gill physiology.

The complex relationships between the structure and function of fish gills have been of interest to comparative physiologists for many years. Morphological plasticity of the gill provides a dynamic mechanism to reversibly alter its structure in response to changes in the conditions experienced by the fish. The best known example of gill remodelling is the growth or retraction of cell masses between the lamellae, a rapid process that alters the lamellar surface area that is exposed to the water (i.e. the functional lamellar surface area). Decreases in environmental O2 availability and/or increases in metabolic O2 demand stimulate uncovering of the lamellae, presumably to increase the capacity for O2 uptake. This review addresses four questions about gill remodelling: (1) what types of reversible morphological changes occur; (2) how do these changes affect physiological function from the gill to the whole animal; (3) what factors regulate reversible gill plasticity; and (4) is remodelling phylogenetically widespread among fishes? We address these questions by surveying the current state of knowledge of gill remodelling in fishes, with a focus on identifying gaps in our understanding that future research should consider.

Using two- and three-dimensional landmark data to examine the shape variation of Elliptio complanata from two heavily impounded rivers in northern New York (USA)

ABSTRACT Despite vast improvements in the quantification of shape variation with geometric morphometric methods, evaluating morphological variation in unionids has remained difficult due to the lack of measurable landmarks on shells and their overall morphological plasticity. In this study, we supplement traditional two-dimensional landmark data with three-dimensional landmark data. Using photogrammetry, we generate three-dimensional models that are landmarked. This approach adds a new, third dimension to capture shape changes, providing a more detailed understanding of the shell topography. With this method, we explore the differences in shell shape along river stretches of two heavily impounded rivers in northern New York (USA). We ask whether isolation by distance, presence of dams and/or difference in land use around sampling localities impact the shell morphologies of Elliptio complanata populations. Our data suggest that, although separated for almost a century, these unionid populations do not show a pattern of increased morphological difference with distance. But we find that broad, rounded morphs that are posteriorly extended occur more frequently in reservoir environments while unaltered river habitats have a higher number of slim and more elongated variants.

Exploring the organic nature, morphological plasticity and ecological significance of Aster like nanoparticles.

The smallest entities in aquatic ecosystems, i.e., femtoplankton, are certainly the largest reservoir of uncharacterized biodiversity. Among them, the discovery of mysterious Aster like nanoparticles has raised many questions about their nature, origin and ecology. Here, we highlight the original nature of this new model, organic and composed of enriched-calcium carbohydrates, with no detection of nucleic acids or proteins. The biosynthesis of these entities seems to be associated with a host in their 11 arms' form prior to their release into the environment. An intriguing aspect of their mode of development is their ability, once free, to change form and maintain their abundance autonomously without metabolism being detected, resulting in an unexpected polymorphism. Their remarkable capacity for massive in situ development and their links with prokaryotes and other microbes suggest a major role in the functioning of aquatic ecosystems. There's no doubt that these new entities are a source of new knowledge not only in the sciences of organic nanoparticles, but also in their ecological importance for aquatic ecosystems.

Intraspecific variation in leaf morphology of three widespread woody species along climatic gradients

Abstract The variation and plasticity of leaf morphology plays a pivotal role in the response to environmental changes for plant individuals. Discovering the large-scale pattern of such variation can reveal plants' general adaptive strategies. We analyzed leaf morphology of three widespread woody species in the northern hemisphere using specimen data from the iDigBio and GBIF databases, to investigate the variations in the individual mean traits, in the inter- and intra-individual variability of traits, and in the allometry between traits, along climatic gradients. We found that larger and wider leaves were associated with warmer, wetter and low-sunlight habitats, while smaller but wider leaves are linked to higher wind speed, indicating the response of leaf morphology to multiple climate stresses. The inter-individual variation in leaf area was smaller in colder and windier conditions, suggesting the trait convergence among individuals under environmental filtering, while the intra-individual variation in leaf relative width was smaller in warmer habitats, indicating the similar growth optimum of leaves within one individual in more favorable conditions. Finally, the allometric exponent between leaf length (X-axis) and width (Y-axis) became greater under lower solar radiation and higher wind speed, while the squared correlation coefficient (r2) indicating phenotypic integration showed a decoupling trend under colder conditions, indicating that climate affected the variation tendency of leaf relative width during leaf enlargement. These results reveal the common patterns of leaf morphology responding to climate variation spatially and underscore the necessity to consider inter- and intra-individual variability when examining plant responses to environmental changes.

Functional Activity of the Antioxidant System of Artemisia Genus Plants in the Republic of Buryatia (Russia) and Its Significance in Plant Adaptation.

Plants are sessile organisms and any changes in environmental factors activate various responses and defense mechanisms. Artemisia plants widely inhabit harsh conditions of arid and semiarid ecosystems. Using two species-a subshrub, Artemisia frigida, and an annual-biennial herb, Artemisia scoparia-the functioning of the antioxidant system of plants in semiarid territories have been examined. The activity of enzymatic antioxidants and the content of non-enzymatic antioxidants in both species as well as the antiradical activity of their extracts have been shown. Although the plants were collected in areas differing in moisture supply, the activity of enzymatic antioxidants and the content of non-enzymatic antioxidants corresponds to their physiological level, within the range of the norm of reaction, in wormwood. Consequently, conditions of differing moisture deficiency do not cause a specific biochemical response at the level of the antioxidant system in the studied species, which confirms their adaptability to these conditions. Meanwhile, A. frigida plants show greater morphological and biochemical plasticity than A. scoparia under changing growth conditions. Both species contain tissue monoterpenoids and sesquiterpenoids, the emission of which provides additional protection against high temperatures and drought. Their composition and contents of phenolic components illustrates the differences in adaptation between perennial and annual plants.

Relationship between phosphorus stoichiometric homeostasis and deepwater adaptability of submerged macrophytes in Erhai Lake, China: Insights from allometric plasticity

The state transition theory suggests that the decline of submerged macrophytes in shallow lakes is closely associated with reduced stoichiometric homeostasis, particularly phosphorus homeostasis (HP). The degradation typically progresses from deeper to shallower regions, indicating a potential positive correlation between the deepwater adaptability (DA) and HP values of submerged macrophytes. Here, we investigated the distribution pattern of submerged macrophytes across different water depths of Erhai Lake to test this hypothesis. The results revealed a significant positive correlation between the DA and HP values of submerged macrophytes. Allometric analysis indicated that the morphological plasticity of submerged macrophytes was linked to their HP. Species with higher HP values, like Potamogeton maackianus, had robust plasticity strategies, particularly “real plasticity”, that enabled them to cope with deeper water stress. In contrast, species with lower HP values (Ceratophyllum demersum and Hydrilla verticillata) experienced nutrient declines, which hindered their adaptation. Additionally, species with higher HP values exhibited closer connections within the plant traits-environment network, indicating that their morphological plasticity adjustments allow better adaptation to the environmental changes caused by increasing water depth. These results confirm the relationship between DA and HP in submerged macrophytes and explain the mechanisms underlying the correlation, thus expanding regime shift theory.

Nutrition affects larval survival and the development of morphological traits in male and female flour beetles, but genital size and shape remains canalised.

The caloric content and macronutrient ratio of diet consumed is a major source of phenotypic variation in most animal populations. While these nutritional effects have been well-documented for a variety of life-history and morphological traits, the effects of nutrition on male genitals are poorly understood but genitals are thought to be more canalised than general morphology and hence less susceptible to variation in nutrition. Even less is known about the effects of nutrition on female genital form, which to our knowledge, have never been investigated. Here we tested for effects of juvenile dietary macronutrients (protein and carbohydrate) on larval survival, adult morphology, including genital size and shape in male and female flour beetles (Tribolium castaneum). We found there was nutritionally induced plasticity in larval survival and morphology, although the latter effect was variable, with body size being most responsive to dietary macronutrients and genital size and shape being least responsive. Functionally equivalent morphological traits in the sexes responded similarly to nutrition. Previously, we showed that the genitalia of male and female T. castaneum are subject to strong stabilising sexual selection, and our current findings suggest that developmental mechanisms reduce the nutritional sensitivity of male and female genitals, possibly to ensure matching during mating.