Morphological Adaptations Research Articles

The Provision of Browse and Its Impacts on the Health and Welfare of Animals at the Zoo: A Review.

Browsers are animals that consume significant proportions of leaves, twigs, and bark from woody plants. These species have evolved morphological, physiological, and behavioral adaptations to subsist on a specialized diet. In zoos and other managed care facilities, the provision of browse in appropriate amounts helps promote positive animal welfare. Feeding on browse fulfills behavioral needs and reduces stereotypies, promotes satiety, and provides opportunities for dietary choice and control. However, there are several obstacles that can prevent institutions from providing browse, including physical and chemical hazards, palatability issues, and the difficulty in quantifying the nutritional value of browse. In addition, providing large enough quantities of browse can be challenging, and fresh browse may be especially difficult to provide for zoos in temperate climates. We describe the methods currently utilized to preserve browse and discuss their strengths and weaknesses. We recommend areas of future research for browse provision in zoos.

Pseudosuchia: Masters of survival and diversification.

In the context of an increasing interest for Pseudosuchia, we have compiled a Special Issue, comprising 14 collaborative studies that deepen our understanding of pseudosuchian evolution. These contributions range from the description of a new taxon to exhaustive reviews of thermometabolism, morphological adaptation, systematics, and detailed investigations into ontogeny, paleoneurology, paleohistology, and paleobiology. Through these papers, we explore the evolutionary history of pseudosuchian archosaurs, spotlighting their rise and diversification following the end-Permian mass extinction.

A tale of long tails: Evolution of host specialization in non‐pollinating fig wasps

Abstract The evolution of host specialization and feeding habits in non‐pollinating fig wasps remains poorly understood. This study investigates these dynamics within the wasp genus Idarnes, which exhibits diverse life strategies and degrees of host specificity. We reconstructed the phylogeny of 57 Idarnes species using four genetic markers—two mitochondrial, one nuclear and one ribosomal—and performed ancestral state reconstructions to elucidate the evolution of host specialization. Our analyses reveal that host monophagy is ancestral in Idarnes, with oligophagy evolving independently in several lineages. Oligophagous species are more prevalent in kleptoparasitic compared to gall‐inducing lineages. Early gallers—which are wasps that colonize figs during the pre‐receptive stage of development—are predominantly monophagous, while some oligophagous species occur in the galler lineage that uses flower ovaries at the fig receptive phase. The relative ovipositor length correlates with the number of host species visited by kleptoparasite species, suggesting morphological adaptations play a role in host specialization. In the gall‐inducing lineages, the use of multiple host species seems not primarily constrained by the ovipositor size but possibly by the capacity of the wasp to induce galls in a non‐typical host species. This study provides valuable insights into the mechanisms driving host specialization in fig wasps, enhancing our understanding of this intricate insect‐plant system.

Differential timing of mitochondrial activation in rat dorsal striatum induced by procedural learning and swimming.

Stressful experiences form stronger memories due to enhanced neural plasticity mechanisms linked to glucocorticoid hormones (cortisol in humans, corticosterone in rats). Among other neural structures, the dorsal striatum plays a role in the corticosterone-induced consolidation of stressful memories, particularly in the cued water maze task. Neural plasticity is related to mitochondrial activity due to the relevance of energy production and signaling mechanisms for functional and morphological neuronal adaptations. Corticosterone has been shown to enhance brain mitochondrial activity by activating glucocorticoid receptors. In this context, striatum functions are susceptible to change in relation to mitochondrial responses. Based on this evidence, we hypothesized that training in the cued water maze would induce an increase in corticosterone levels and mitochondrial activity (mitochondrial membrane potential and calcium content) in the dorsal striatum, and that these adaptations might be related to memory consolidation of the task. We used an ELISA assay to evaluate plasma and striatal corticosterone levels; mitochondrial activity was determined with the florescent probes MitoTracker Red (mitochondrial membrane potential) and Rhod-2 (calcium content) in brain slices containing the dorsal striatum of rats trained in the cued water maze and euthanized at different times after training (0.5, 1.5, or 6.0 h). We also analyzed the effect of post-training inhibition of striatal mitochondrial activity by OXPHOS complex 1 inhibitor rotenone, on the consolidation of the cued water maze task. We found that cued water maze training induced an increase in corticosterone levels and a time-dependent elevation of mitochondrial membrane potential and mitochondrial calcium content in the dorsal striatum. Unexpectedly, rotenone administration facilitated the retention test. Altogether, our results suggest that enhanced mitochondrial activity in the dorsal striatum is relevant for cued water maze consolidation. The increase in mitochondrial activity was contextually associated with an elevation of corticosterone in plasma and the dorsal striatum. Additionally, our swimming groups also showed an increase in mitochondrial activity in the dorsal striatum, but with a different pattern, which could suggest a differential functional adaptation in this structure.

RANK drives structured intestinal epithelial expansion during pregnancy.

During reproduction, multiple species such as insects and all mammals undergo extensive physiological and morphological adaptions to ensure health and survival of the mother and optimal development of the offspring. Here we report that the intestinal epithelium undergoes expansion during pregnancy and lactation in mammals. This enlargement of the intestinal surface area results in a novel geometry of expanded villi. Receptor activator of nuclear factor-κΒ (RANK, encoded by TNFRSF11A) and its ligand RANKL were identified as a molecular pathway involved in this villous expansion of the small intestine in vivo in mice and in intestinal mouse and human organoids. Mechanistically, RANK-RANKL protects gut epithelial cells from cell death and controls the intestinal stem cell niche through BMP receptor signalling, resulting in the elongation of villi and a prominent increase in the intestinal surface. As a transgenerational consequence, babies born to female mice that lack Rank in the intestinal epithelium show reduced weight and develop glucose intolerance after metabolic stress. Whereas gut epithelial remodelling in pregnancy/lactation is reversible, constitutive expression of an active form of RANK is sufficient to drive intestinal expansion followed by loss of villi and stem cells, and prevents the formation of Apcmin-driven small intestinal stem cell tumours. These data identify RANK-RANKL as a pathway that drives intestinal epithelial expansion in pregnancy/lactation, one of the most elusive and fundamental tissue remodelling events in mammalian life history and evolution.

Comparison of the fine structure of hair in the ancient Lena horse (†Equus lenensis Russanov 1968) and the domestic horse (Equus caballus caballus Linnaeus 1758) of native northern breeds

Using SEM and morphometry, the fine structure of guard hairs and the elements of their medulla were compared in the Lena horse (Equus lenensis) and the domestic horse (E. caballus caballus) of five breeds. A number of features of hair fine structures have been identified, most clearly revealed when comparing horses of the northern (Mezen, Pechora, Yakut) and southern (Arabian, Akhal-Teke) groups of breeds. Seasonal changes in the structure of hair in horses of northern breeds (thickening of the hair medulla and an increase in the volume of its air cavities) indicate an increase in the heat-protecting properties of wool in winter, this being of adaptive significance. Both Pleistocene and recent domestic horses are shown to have developed convergent morphological adaptations of wool to low air temperatures.

Physics of sliding on water explains morphological and behavioural allometry across a wide range of body sizes in water striders (Gerridae).

Laws of physics shape adaptations to locomotion, and semiaquatic habitats of water striders provide opportunities to explore adaptations to locomotion on water surface. The hydrodynamics of typical propelling with symmetrical strokes of midlegs is well understood, but the subsequent passive sliding on surface has not been explored. We hypothesized that morphological and behavioural adaptations to sliding vary by body size. Based on empirical observations of water striders across a wide range of body size, we constructed a theoretical model of floating and resistance during sliding. Our model predicts that large water striders are too heavy to support anterior body on forelegs during sliding when their two midlegs are off the surface symmetrically during a recovery phase after stroke in symmetric gait. Heavy species should either (i) develop sufficiently long forelegs to support their anterior body on surface during symmetric gait or (ii) use asymmetric gait when one forward-extended midleg supports anterior body. Observations were consistent with these predictions. Additionally, medium-sized insects were observed to switch between symmetrical and asymmetrical gait in the manner that reduces sliding resistance. Our results illustrate how habitat-specific physical processes cause morphological and behavioural diversity associated with body size among biological organisms.

Comparative Morphology of the Extrinsic and Intrinsic Leg Musculature in Dictyoptera (Insecta: Blattodea, Mantodea).

Insect legs, as primarily locomotory devices, can show a tremendous variety of morphological modifications providing a multitude of usages. The prehensile raptorial forelegs of praying mantises (Mantodea) are a prominent example of true multifunctionality since they are used for walking while being efficient prey-capturing and grasping devices. Although being mostly generalist arthropod predators, various morphological adaptations due to different environmental conditions occur across Mantodea. Recently, the general mantodean morphology, and particularly their raptorial forelegs, received an increased interest. Yet, knowledge about the evolutionary transition from walking to prey-grasping legs is still scarce. From evolutionary and functional perspectives, the question arises: what changes were necessary to achieve the strongly modified raptorial forelegs-while keeping walking ability-and how does the foreleg morphology differ from the remaining four walking legs? In this context, we investigated the musculature of the raptorial forelegs in seven phylogenetically distant mantodeans, including pterothoracic legs in four of them, using high-resolution microcomputed tomography and dissection. To understand the results from an evolutionary perspective, we additionally examined all three pairs of unmodified walking legs of the closest sister group-Blattodea. We updated the knowledge of blattodean morphology, revealing differences in cuticle structures of the coxal articulation of the first pair of legs between the two orders and a shared musculature set-up in all pairs of legs among later-branching mantodeans. Interestingly, the early branching species Metallyticus splendidus and Chaeteessa sp. show several muscular characteristics, otherwise found exclusively in one or the other order, with a few procoxal muscles showing an intermediate state between the two orders. Studying the evolutionary transition from a walking leg to a raptorial leg will help to understand the character evolution of this highly specialized biomechanical system from a purely locomotory appendage to a multi-functional device with all related amenities and constraints.

Role of LED (Light Emitting Diode) Light Illumination on the Growth of Plants in Greenhouse Farming-Hydroponics: IOT Technology

This review paper of literature highlights role of Light Emitting Diode (LED) on the growth of plants under controlled conditions of greenhouse farming particularly hydroponics. “Internet of Things (IOT)” is a system of interconnected computing devices, sensors, objects, microcontrollers, and cloud servers that can transmit data across a network and control other devices remotely without human intervention. Light Emitting Diode (LED) is a more efficient, versatile, lasts longer, highly energy-efficient, directional, narrow light spectrum, low power consumption, and little heat production. Common LED colors include amber, red, green, and blue. Hydroponic grow lights are designed to mimic the natural light that plants need for photosynthesis. Plants can only use the spectrum of visible light to produce photosynthesis, and this narrow spectrum (400 to 700 nanometer) is recognized as the Photosynthetically Active Radiation (PAR). The development and growth of diverse plant species can be influenced differently by a variety of colored LED lights. LED illumination provides an efficient way to improve yield and modify plant properties. Therefore, LED systems plays an important role in controlling morphological, genetic, physiological, chemical properties, increasing the synthesis of a variety of beneficial secondary metabolites, and optobiological interactions of plants in greenhouse farming. In general, red and blue light is essential for maximizing the photosynthesis process due to their strong absorption by the plant chlorophyll molecules. LED illumination sources are increasingly being utilized to enhance the growth rate of vegetables and herbs cultivated in greenhouses worldwide. LED illumination spectrum manipulation could enable significant morphological adaptations, and identification of the wavelength ranges is required to increase the plant photosynthesis process.

Redescription of Euscorpius studentium Based on Adult Specimens; Updated Classification of Cavernicolous Euscorpiidae; and Review of Cavernicolous Scorpions in the Balkans

Cavernicolous scorpions are difficult to collect and study due to their often inaccessible habitats. Some have evolved unique morphological adaptations, known as troglomorphies, including reduced sclerotization and pigmentation, reduction and/or loss of eyes, attenuation and elongation of the appendages, which assist them to thrive in dark, humid and low-energy input environments. Cavernicolous scorpions are classified into accidentals, trogloxenes, troglophiles, and troglobites. The Balkans, and particularly the Dinaric Karst region, host a diverse cave-adapted fauna, including scorpions. Despite an 1895 report of a blind scorpion from Bosnia and Herzegovina, the first truly troglobitic European scorpion, Euscorpius studentium Karaman, 2020, was only described a few years ago, based on two immature specimens. In the present contribution, this unique species is redescribed based on the first adult specimens; the ecological classification of all currently known cavernicolous Euscorpiidae Laurie, 1896, is updated; a key to the identification of cavernicolous scorpions occurring in the Dinaric Karst is provided; and the historical and geographical factors affecting the distribution and conservation of cavernicolous scorpions in the Balkans is reviewed.

A review of the non-semiaquatic adaptations of extinct crocodylomorphs throughout their fossil record.

Crocodylomorphs constitute a clade of archosaurs that have thrived since the Mesozoic until today and have survived numerous major biological crises. Contrary to historic belief, their semiaquatic extant representatives (crocodylians) are not living fossils, and, during their evolutionary history, crocodylomorphs have evolved to live in a variety of environments. This review aims to summarize the non-semiaquatic adaptations (i.e., either terrestrial or fully aquatic) of different groups from different periods, highlighting how exactly those different lifestyles are inferred for those animals, with regard to their geographic and temporal distribution and phylogenetic relationships. The ancestral condition for Crocodylomorpha seems to have been a terrestrial lifestyle, linked with several morphological adaptations such as an altirostral skull, long limbs allowing a fully erect posture and a specialized dentition for diets based on land. However, some members of this clade, such as thalattosuchians and dyrosaurids display adaptations for an opposite, aquatic lifestyle, interestingly inferred from the same type of morphological observations. Finally, new techniques for inferring the paleobiology of those extinct animals have been put forward in the last decade, appearing as a complementary approach to traditional morphological descriptions and comparisons. Such is the case of paleoneuroanatomical (CT scan data), histological, and geochemical studies.

DESCRIPTION OF THE SPECIESBRADYBAENA PLECTOTROPIS LIVING IN THE VICINITY OF THE NARYN RIVER

Objective: This study aimed to investigate the terrestrial malacofauna in the Naryn River region, with a specific focus on Bradybaena plectotropis in Grigorievskoe Gorge, Kyrgyzstan, to enhance understanding of its ecological roles and biological features. Methods: Field surveys and anatomical analyses were conducted in August 2024, covering diverse biotopes across Grigorievskoe Gorge and Boom Gorge. Forty specimens were collected, documented, and examined for morphological and reproductive characteristics to determine ecological preferences and habitat distribution. Results: The study identified Bradybaena plectotropis as a dominant species in the region, demonstrating significant morphological adaptations and ecological versatility. Its roles in soil formation, organic matter decomposition, and trophic chains underscore its ecological importance. Additionally, its presence across varied biotopes highlights its adaptability and widespread distribution. Novelty: This research provides the first comprehensive faunistic and anatomical study of Bradybaena plectotropis in the Naryn River region, offering valuable insights into its taxonomy, ecological roles, and conservation relevance in Kyrgyzstan's mountainous ecosystem.

Unique insights into morphological characterization and functional adaptation of the scaly shank skin in aquatic and terrestrial birds

The avian skin is a vital barrier against external effects and undergoes modification to adapt to the different ecosystems. The current study focused on the comprehensive study of the scaly shank skin of aquatic birds, Egyptian Balady Duck (EBD) as well as terrestrial birds, Broad Breasted White Turkey (BBWT) via gross anatomy, histology, and scanning electron microscopy with ED-XRF analysis. The shank skin color was yellow to black in EBD and creamy-white in BBWT. Gross anatomy exhibited two types of scales around the shank: scute and scutella scales in EBD and four types: scute, scutella, reticula, and cancella (interstitial) scales in BBWT. Most scales were non-overlapped and separated by sulci in both birds except those on the dorsum of the shank of BBWT. SEM of the descaled skin revealed an irregular surface due to keratinocytes defining a polygonal texture in EBD and Langerhans cells (a large oval-shaped cell body with abundant long projections) attached to neighboring keratinocytes in BBWT. Histologically, the epidermal and dermal layers varied among the different skin aspects of the shanks of both birds. Langerhans cells were seen within the basal cell layer of the stratum germinativum and collagen fibers of the dermal stratum superficiale. Melanocytes were observed in the stratum basale in EBD. In both birds, abundant telocytes and fibroblasts were distributed within the dermal layers, with excessive adipose tissue in the dermis of the shank skin of EBD. According to the results of the ED-XRF analysis of the scaly shank skin, elements and oxides were present in both species. In conclusion, the findings of the present study reflect the correlations between the functional morphology of shank skin and the bird habitats.

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.

Delineating early life stages of Belone belone: analysis of external morphology and postcranial skeletal development of the garfish

During fish larvae development functional, morphological, and physiological adaptations are key in larval survival strategies and can determine mortality bottlenecks. For many fish groups such as needlefish, which play crucial roles in marine food webs, studies on early life stages are almost lacking. Herein, the development, with focus on the postcranial skeleton, of the garfish Belone belone (Linnaeus, 1761) is described and a staging system is introduced. Ten larval and juvenile life stages are proposed in three main phases: yolk sac, larval, and juvenile development. During the yolk sac phase the garfish deplete their yolk reservoirs and finish the development of their unpaired fins. During the larval period the lower jaw elongates and the needlenose stage is reached. In the juvenile phase, the upper jaw elongates until both jaws are almost equally long. Since B. belone larvae develop much of their postcranial skeleton in the late embryonic and yolk sac phases they might not experience a severe bottleneck in this early stage such as many other marine fish species. Therefore, young garfish could be more resilient to environmental changes.

Wolffia globosa, a novel crop species for protein production in space agriculture

Space agriculture, pivotal for sustainable extraterrestrial missions, requires plants that can adapt to altered gravitational conditions. This study delves into the adaptive responses to altered gravity of Wolffia globosa, an aquatic plant known for its rapid growth and high nutritional value. The research aimed to analyse the effect of simulated microgravity and hypergravity on relative growth rate (RGR), morphological characteristics, protein content, and the correlation between plant size and growth rate of Wolffia globosa. The study highlighted the responses of the species to altered gravity, uncovering inherent variability among seven different clones of W. globosa. Results show a base variability among clones in terms of RGR, size and protein content. Furthermore, some clones are affected by simulated microgravity, showing a decrease in RGR. Differently, under hypergravity, clones showed RGR higher than in 1 g control, therefore revealing a novel plant response to hypergravity. Morphological adaptations to gravity alterations were also evident. Among the studied clones, significant morphological changes were observed, further underlining the peculiar adaptation to the hypergravity environment. Differently, under simulated microgravity, morphology was generally stable across clones. A key finding of the study was the significant negative correlation between RGR and the physical dimensions of the plants: the fastest growth was associated with the smallest dimensions of the plants. This correlation might have practical implications in selecting clones for space cultivation, that leads to compact yet highly productive clones. The analysis of the protein content of all the clones revealed mostly no significant changes under hypergravity. Otherwise, a general decrease in protein content was observed under simulated microgravity. Overall, the study confirms the suitability of W. globosa for space agriculture and provides new insights into the perspective of using W. globosa as an alternative crop species for protein production for manned Space missions. Furthermore, it underscores the need for focusing on the clones and the selection of the W. globosa plants that are best adapted to the environmental conditions of space; therefore, selecting those with the best combination of biomass production (by means of growth rate, size), and protein content.

Unveiling Thrips (Thysanoptera) as Nature's Unsung Pollinators: A Survey From Obligatory Thripophily to Thrips as Supplementary Pollinators

ABSTRACTThrips are minute, paraneopteran insects with diverse ecological histories and plant associations, encompassing herbivory, fungivory, pollination and predation. They are typically not widely adored insects as many species are regarded to be destructive crop pests and vectors of crop diseases. Nevertheless, certain thrips play a significant role in pollination as they traverse from flower to flower with pollen attached to their bodies. However, most studies on relationships between flowering plants and pollinators have overlooked the prevalence and association of thrips with flowers, and the pollination services were often incorrectly attributed to wind, bees or other agents. This is primarily due to the minute size and cryptic behaviour of thrips, their limited range of movement and minimal structural modifications to carry and disperse pollen. In recent times, the involvement of thrips in pollination was investigated by many researchers and their role was established partly or fully in several angiosperm families. Their role in pollination through specialised thripophily, as minor or secondary pollinators, or via ambophily is well‐established now. The present paper reviews the evidence of pollen transfer by thrips, obligate and nonobligate pollination relationships between plants and pollinator thrips, evolutionary aspects of thripophily, morphological and physiological adaptations in thrips and floral syndromes associated with thripophily.

The role of ethylene in the regulation of plant response mechanisms to waterlogging stress.

Waterlogging stands as a common environmental challenge, significantly affecting plant growth, yield, and, in severe cases, survival. In response to waterlogging stress, plants exhibit a series of intricate physiologic, metabolic, and morphologic adaptations. Notably, the gaseous phytohormone ethylene is rapidly accumulated in the plant submerged tissues, assuming an important regulatory factor in plant-waterlogging tolerance. In this review, we summarize recent advances in research on the mechanisms of ethylene in the regulation of plant responses to waterlogging stress. Recent advances found that both ethylene biosynthesis and signal transduction make indispensable contributions to modulating plant adaptation mechanisms to waterlogged condition. Ethylene was also discovered to play an important role in plant physiologic metabolic responses to waterlogging stress, including the energy mechanism, morphologic adaptation, ROS regulation and interactions with other phytohormones. The comprehensive exploration of ethylene and its associated genes provides valuable insights into the precise strategies to leverage ethylene metabolism for enhancing plant resistance to waterlogging stress.

Immature stages and natural history of Eruga unilabiana (Hymenoptera: Ichneumonidae), an ectoparasitoid of two linyphiid spiders

AbstractWasps from the Polysphincta genus group (Hymenoptera: Ichneumonidae: Pimplinae) are currently the only parasitoid wasps that are ectoparasitoids of spiders. The species of the group exhibit several morphological and behavioral adaptations, which allow exploiting their host spiders. Here, we describe the external morphology, behavior and natural history of the immature stages of a Darwin wasp Eruga unilabiana Pádua & Sobczak, 2018, a parasitoid of sheet‐weaving spiders, Sphecozone sp. and Eurymorion sp. (Linyphiidae). The egg of E. unilabiana is a white mass that is deposited in the anterior region of the spider's abdomen. First stage larvae partially emerge from the egg's chorion. Second stage larvae have a body divided into 13 segments and induce spiders to build a modified web. The third stage larvae have eight pairs of retractable dorsal tubercles with tiny little hooks that help the larvae hang and move on the web threads after the spider dies. These results indicate that the immature stages of E. unilabiana present the same basic morphological and behavioral characteristics already known for the species of the group. However, the last stage larva's strategy of moving first to hang on the web threads before killing the spider is the first record in the group and more studies are needed to assess whether this behavior is adaptive for the wasp.

High-resolution chromosome-level genome of Scylla paramamosain provides molecular insights into adaptive evolution in crabs

BackgroundEvolutionary adaptation drives organismal adjustments to environmental pressures, exemplified in the diverse morphological and ecological adaptations seen in Decapoda crustaceans, particularly brachyuran crabs. Crabs thrive in diverse ecosystems, from coral reefs to hydrothermal vents and terrestrial habitats. Despite their ecological importance, the genetic mechanisms underpinning their developmental processes, reproductive strategies, and nutrient acquisition remain poorly understood.ResultsHere, we report a comprehensive genomic analysis of the green mud crab Scylla paramamosain using ultralong sequencing technologies, achieving a high-quality chromosome-level assembly. The refined 1.21 Gb genome, with an impressive contig N50 of 11.45 Mb, offers a valuable genomic resource. The genome exhibits 33,662 protein-coding genes, enriched in various pathways related to development and environmental adaptation. Gene family analysis shows expansion in development-related pathways and contraction in metabolic pathways, indicating niche adaptations. Notably, investigation into Hox gene regulation sheds light on their role in pleopod development, with the Abd-A gene identified as a linchpin. Post-transcriptional regulation involving novel-miR1317 negatively regulates Abd-A levels. Furthermore, the potential role of fru gene in ovarian development and the identification of novel-miR35 as a regulator of Spfru2 add complexity to gene regulatory networks. Comparative functional analysis across Decapoda species reveals neo-functionalization of the elovl6 gene in the synthesis of long-chain polyunsaturated fatty acids (LC-PUFA), suggesting its importance in environmental adaptation.ConclusionsOur findings shed light on various aspects of crab biology, including genome sequencing, assembly, and annotation, as well as gene family expansion, contraction, and regulatory mechanisms governing crucial developmental processes such as metamorphosis, reproductive strategies, and fatty acid metabolism.