Zoological Science最新文献_第2页

Beyond Individuality: Developmental and Evolutionary Deviations in Animal Body Plans. 超越个性：动物身体计划的发展和进化偏差。

IF 1 4区生物学

Zoological Science Pub Date : 2026-02-01 DOI: 10.2108/zs250076

Toru Miura, Kohei Oguchi

{"title":"Beyond Individuality: Developmental and Evolutionary Deviations in Animal Body Plans.","authors":"Toru Miura, Kohei Oguchi","doi":"10.2108/zs250076","DOIUrl":"https://doi.org/10.2108/zs250076","url":null,"abstract":"The emergence of multicellularity was a key innovation in metazoan evolution, enabling the development of functionally integrated individuals. Animal individuality is typically defined by organ systems such as the nervous, muscular, and digestive systems, which are established during embryogenesis and regulated by conserved patterning genes, including Hox genes. However, some animal lineages deviate from this canonical model. In eusocial and colonial species, certain individuals specialize in specific tasks and lose the ability to perform others, such as reproduction, despite sharing identical (or nearly identical) genomes. These morphs arise through postembryonic developmental plasticity, suggesting the presence of mechanisms that enable switching between alternative developmental pathways. Other lineages exhibit life strategies that require departures from standard developmental sequences. For example, in syllid annelids, reproductive units form at the posterior end and detach to spawn. Similarly, novel body architectures have evolved in several lineages - for instance, the pentaradial symmetry of echinoderms or the benthic forms of platyctenid ctenophores - which differ markedly from ancestral forms and are often linked to adaptive radiation. These examples illustrate that, although animals are generally adapted to ecological niches through integrated body plans, many lineages retain a surprising degree of developmental and evolutionary flexibility. This plasticity enables transitions that challenge conventional definitions of individuality and highlight the diversity of organizational strategies in the animal kingdom.","PeriodicalId":24040,"journal":{"name":"Zoological Science","volume":"43 1","pages":"23-34"},"PeriodicalIF":1.0,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147285126","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Expression Pattern of the Hox Genes in Caprellids That Have Lost Some of Their Thoracic Legs and Abdominal Segments. Hox基因在失去部分胸肢和腹部节段的Caprellids中的表达模式

IF 1 4区生物学

Zoological Science Pub Date : 2026-02-01 DOI: 10.2108/zs250057

Mizuki Kajino, Yoshiaki Morino, Hiroshi Wada

{"title":"Expression Pattern of the Hox Genes in Caprellids That Have Lost Some of Their Thoracic Legs and Abdominal Segments.","authors":"Mizuki Kajino, Yoshiaki Morino, Hiroshi Wada","doi":"10.2108/zs250057","DOIUrl":"https://doi.org/10.2108/zs250057","url":null,"abstract":"The unique body plan of caprellids is likely to have derived from the gammarid body plan through the loss of abdominal segments and walking legs in the fourth and fifth thoracic segments. In this study, we investigated whether the caprellid body plan evolved through changes in Hox gene expression. We found that most caprellid Hox genes exhibit a comparable expression pattern with that of gammarids. Notably, Ubx, which plays a crucial role in the development of the morphology of the thoracic legs of gammarids, is expressed in the corresponding thoracic segments of caprellids. Therefore, it is likely that the evolutionary loss of the thoracic legs in caprellids occurred through the modification of a downstream target of Ubx. This expression pattern is consistent with a previous report that gammarid Ubx is required for gill development because caprellids develop gills in the thoracic segments where the legs were lost. We also found that caprellids possess Abd-B, the ortholog of which in gammarids is expressed in abdominal segments. Caprellid Abd-B is specifically expressed in the thoracic legs, and this neofunctionalization may have helped to retain this gene in the caprellid genome.","PeriodicalId":24040,"journal":{"name":"Zoological Science","volume":"43 1","pages":"90-94"},"PeriodicalIF":1.0,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147285259","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Non-Contiguous and Multi-Regional Expression of Pancreas-Related Genes along the Lancelet Gut. 胰腺相关基因沿Lancelet肠的非连续和多区域表达。

IF 1 4区生物学

Zoological Science Pub Date : 2026-02-01 DOI: 10.2108/zs250035

Haruka Fujiwara, Satoshi Nakayama, Rin Iguchi, Toshio Sekiguchi, Yasunori Sasakura, Masato Kiyomoto, Michio Ogasawara

{"title":"Non-Contiguous and Multi-Regional Expression of Pancreas-Related Genes along the Lancelet Gut.","authors":"Haruka Fujiwara, Satoshi Nakayama, Rin Iguchi, Toshio Sekiguchi, Yasunori Sasakura, Masato Kiyomoto, Michio Ogasawara","doi":"10.2108/zs250035","DOIUrl":"https://doi.org/10.2108/zs250035","url":null,"abstract":"Deuterostomes generally share a functional digestive system involving the sequential steps of ingestion, digestion, absorption, and elimination along their one-way gut. Previous gene expression studies on pancreas-related exocrine digestive enzymes (XDEs), pancreas-related transcription factors (TFs), and ParaHox genes in the ascidian Ciona robusta showed non-contiguous and multi-regional pancreatic features along the Ciona gut. The combination of classical in situ hybridization and recent RNA-seq techniques in lancelets has allowed the fundamental features of the gut in basal chordates (lancelets and ascidians) to be examined in more detail. In the present study, we investigated the spatial expression of pancreas-related XDE and TF genes with a focus on their regionality in the adult lancelet gut. Whole-mount in situ hybridization using Branchiostoma japonicum revealed non-contiguous and multiple pancreatic regions in the lancelet gut. Public bulk RNA-seq data on lancelets (Branchiostoma belcheri, B. floridae, and B. lanceolatum) also supported the multi-regional distribution of pancreatic features along the lancelet gut. In addition, single-cell RNA-seq data indicated that the lancelet hepatic caecum comprised multiple cell clusters with the differential gene expression of pancreas-related XDEs, Pdx, and Cdx. Gene knockout experiments on ascidian Pdx suggested that \"the multi-regional expression of pancreas-related XDE genes\" in basal chordates is associated with Pdx-independent regulation.","PeriodicalId":24040,"journal":{"name":"Zoological Science","volume":"43 1","pages":"106-117"},"PeriodicalIF":1.0,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147285366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Canonical Wnt/β-Catenin Signaling Promotes Pelvic Fin Bud Initiation in Zebrafish. 典型Wnt/β-Catenin信号通路促进斑马鱼盆鳍芽形成。

IF 1 4区生物学

Zoological Science Pub Date : 2026-02-01 DOI: 10.2108/zs250054

Yusaku Nakamura, Asato Irifune, Toru Kawanishi, Mikiko Tanaka

{"title":"Canonical Wnt/β-Catenin Signaling Promotes Pelvic Fin Bud Initiation in Zebrafish.","authors":"Yusaku Nakamura, Asato Irifune, Toru Kawanishi, Mikiko Tanaka","doi":"10.2108/zs250054","DOIUrl":"https://doi.org/10.2108/zs250054","url":null,"abstract":"In vertebrates, anterior (forelimbs and pectoral fins) and posterior (hindlimbs and pelvic fins) paired appendages arise from specific regions of the lateral plate mesoderm. In zebrafish, pectoral fin development illustrates a tightly coupled process in which fin field regionalization and subsequent bud initiation occur in close succession. Regionalization is governed by TBX5, which also promotes bud outgrowth. Canonical Wnt/β-catenin signaling is involved in these processes. In contrast, pelvic fin development is temporally dissociated: the presumptive pelvic fin field is regionalized during early embryogenesis, whereas fin bud initiation does not occur until metamorphosis, approximately 3 weeks later. This separation provides a unique opportunity to examine the distinct roles of Wnt/β-catenin signaling in early field regionalization and later bud initiation. Here, we show that canonical Wnt/β-catenin signaling is inactive during early pelvic fin field regionalization but is essential for fin bud initiation. Wnt/β-catenin activity, represented as GFP signals in Tg(Tcf/Lef-miniP:dGFP), was undetectable in the pelvic region during early embryogenesis but became evident in both the epithelium and mesenchyme of the pelvic fin bud during metamorphosis. Notably, expression of wnt8a, which activates this pathway in the early intermediate mesoderm, was not detected in the pelvic fin region at the time of bud formation. Pharmacological inhibition of Wnt/β-catenin signaling at metamorphic stages impaired pelvic fin bud outgrowth. These findings suggest that canonical Wnt/β-catenin signaling may not be involved in the early regionalization of the pelvic fin field but is essential for the later initiation of pelvic fin bud formation in zebrafish.","PeriodicalId":24040,"journal":{"name":"Zoological Science","volume":"43 1","pages":"81-89"},"PeriodicalIF":1.0,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147285187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evolution of the Jaw Joint and Middle Ear Morphologies in the Lineage Towards Birds. 鸟类谱系中下颌关节和中耳形态的进化。

IF 1 4区生物学

Zoological Science Pub Date : 2026-02-01 DOI: 10.2108/zs250108

Takumi Watanabe, Fernando E Novas, Tatsuya Hirasawa

{"title":"Evolution of the Jaw Joint and Middle Ear Morphologies in the Lineage Towards Birds.","authors":"Takumi Watanabe, Fernando E Novas, Tatsuya Hirasawa","doi":"10.2108/zs250108","DOIUrl":"https://doi.org/10.2108/zs250108","url":null,"abstract":"In tetrapod evolution, the middle ear evolved independently at least four times and represents key innovations for airborne hearing. As the tympanic membrane developed at the interface between the mandibular and hyoid arches, the evolution of middle ears likely involved modifications of jaw joint morphologies. The caudal end of the lower jaw in extant birds accompanies the medial and caudal processes, while the other extant diapsids possess a single process, namely the retroarticular process (RAP). The evolutionary process of these skeletal morphologies, however, remained unclear. Here we examined embryonic developments of the chicken, American alligator, and Chinese soft-shelled turtle, as well as the fossil record, to show that the medial process of the birds is homologous with the retroarticular process. During embryonic development of the chicken, the caudal end of the developing lower jaw became shifted medially, and subsequently the caudal process was secondarily formed. This fact together with the fossil data of Mesozoic theropods indicates that the medial process of the avian lower jaw would be homologous with the RAP. Based on our observations, the invagination of the external auditory meatus likely involves the infolding of the hyoid arch elements including the RAP. Considering the medially oriented RAP as an osteological correlate of the deep external auditory meatus seen in the extant birds, the deep ear canal can be traced back to the common ancestor of coelurosaurian dinosaurs.","PeriodicalId":24040,"journal":{"name":"Zoological Science","volume":"43 1","pages":"72-80"},"PeriodicalIF":1.0,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147285231","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Vertebrate Hox Clusters as Transposon Repellents Against the Genomic Accordion Model. 脊椎动物Hox簇作为转座子对基因组手风琴模型的排斥。

IF 1 4区生物学

Zoological Science Pub Date : 2026-02-01 DOI: 10.2108/zs250058

Shigehiro Kuraku

{"title":"Vertebrate Hox Clusters as Transposon Repellents Against the Genomic Accordion Model.","authors":"Shigehiro Kuraku","doi":"10.2108/zs250058","DOIUrl":"https://doi.org/10.2108/zs250058","url":null,"abstract":"Hox genes, organized in compact genomic clusters, have been central to developmental biology for decades since the discovery of homeotic transformations. Their spatiotemporally regulated expressions strikingly parallel genomic order (3' to 5'), reflecting a deeply conserved blueprint underlying animal form. Advances in genome sequencing have further revealed their unique features, including a remarkably constant length, typically around 100 kilobases in vertebrates, and a striking scarcity of repetitive elements, which commonly reshape genome architecture elsewhere. Given that intergenic regions are often prone to transposable elements and other types of repeats, Hox clusters provide a compelling model for studying genomic restraint. This review highlights the structural conservation of Hox clusters, characterized by the active exclusion of disruptive sequences and cluster size invariance, alongside rare exceptions recently documented. These constrained genomic segments likely play a fundamental role in maintaining the integrity of developmental programs that sculpt animal morphology over vast evolutionary timescales. Exploring Hox gene clusters thus offers a window into the balance of stability and lability that shapes genomes and forms, deepening our understanding of how genomic organization influences the evolution and diversity of animal body plans.","PeriodicalId":24040,"journal":{"name":"Zoological Science","volume":"43 1","pages":"35-43"},"PeriodicalIF":1.0,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147285321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Ontogenic Development of the Acrocoracoid Process Responsible for the Evolution of Avian Flapping Flight. 鸟类扑翼飞行演化中喙突的个体发育。

IF 1 4区生物学

Zoological Science Pub Date : 2026-02-01 DOI: 10.2108/zs250113

Yawara Takeda, Taira Kuramoto-Ahuja, Sayuri Yonei-Tamura, Hirotoshi Shibuya, Masaru Tamura, Masahiro Uesaka, Koji Tamura

{"title":"Ontogenic Development of the Acrocoracoid Process Responsible for the Evolution of Avian Flapping Flight.","authors":"Yawara Takeda, Taira Kuramoto-Ahuja, Sayuri Yonei-Tamura, Hirotoshi Shibuya, Masaru Tamura, Masahiro Uesaka, Koji Tamura","doi":"10.2108/zs250113","DOIUrl":"https://doi.org/10.2108/zs250113","url":null,"abstract":"When modern birds engage in powered flight by flapping their wings, the upstroke movement is produced mainly by a ventrally located muscle called the musculus (m.) supracoracoideus. To achieve this unique mechanism for elevating the humerus, birds have evolved the triosseal canal, a tunnel-like structure which deflects the tendon of the m. supracoracoideus. This canal comprises bony projections of three different skeletal elements of the pectoral girdle (i.e., scapula, coracoid, and clavicle). Importantly, the acrocoracoid process of the coracoid structurally constitutes an essential component for the realization of the triosseal canal's function. Consequently, it has been identified as a key morphological feature for flapping in modern birds. Although limb and girdle development has been extensively studied using avian embryos, the morphogenesis of the avian coracoid itself remains poorly described. To address this knowledge gap, we performed morphological and histological analyses of the shoulder musculoskeletal system of the avian embryo, focusing on the development of the acrocoracoid process. We found that the acrocoracoid process emerges during embryonic development as a lateral protrusion of the dorsal coracoid. Meanwhile, the tendon of the m. supracoracoideus elongates laterally. Using histological analysis, we demonstrate that several shoulder and limb muscles, including the mm. biceps brachii, coracobrachialis, and deltoideus minor, attach to the acrocoracoid process during its development. Our results provide the first detailed description of the ontogenic development of the acrocoracoid process.","PeriodicalId":24040,"journal":{"name":"Zoological Science","volume":"43 1","pages":"61-71"},"PeriodicalIF":1.0,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147285385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Emergence of a Central Nervous System: A Two-Step Evolutionary Model Suggested by Sea Urchin Experiments. 中枢神经系统的出现：由海胆实验提出的两步进化模型。

IF 1 4区生物学

Zoological Science Pub Date : 2026-02-01 DOI: 10.2108/zs250055

Shunsuke Yaguchi

{"title":"Emergence of a Central Nervous System: A Two-Step Evolutionary Model Suggested by Sea Urchin Experiments.","authors":"Shunsuke Yaguchi","doi":"10.2108/zs250055","DOIUrl":"https://doi.org/10.2108/zs250055","url":null,"abstract":"The centralized nervous system (CNS) is a key innovation of bilaterian animals, enabling complex behaviors and body plans. However, how a CNS evolved from ancestral nerve nets remains unresolved. Here, drawing on experimental manipulations in sea urchin embryos, I propose a two-step model for the evolutionary emergence of a CNS, focusing on how signaling pathways partition the embryonic ectoderm. First, an anterior neuroectodermal domain-analogous to a proto-brain field-was specified independently of TGF-β signaling via Wnt-mediated anterior restriction, a mechanism observed even in cnidarians. Second, BMP and Nodal signaling were co-opted to define non-neural ectoderm, restricting neurogenesis in the posterior and creating a condensed, cord-like domain. The integration of these two patterning systems enabled neurons to accumulate along specific axial regions rather than being dispersed across the body. Sea urchin embryos offer a powerful deuterostome model to test this hypothesis. Their ectoderm is sharply divided into anterior and posterior neurogenic territories, separated by TGFβ-signaling-specified non-neural ectoderm. Blocking Wnt signaling leads to ectoderm-wide anterior neurogenesis, while inhibiting TGFβ-signaling causes neurogenesis to expand across the entire ectoderm. These findings strongly support the \"neural default model\" and underscore the importance of combining Wntbased anterior patterning with TGFβ-signaling-mediated neural restriction in CNS centralization. Although the idea is not entirely new, the data from sea urchins provide rare experimental evidence for how ancient axial patterning systems could have cooperatively shaped the emergence of a centralized nervous system in early bilaterians.","PeriodicalId":24040,"journal":{"name":"Zoological Science","volume":"43 1","pages":"118-128"},"PeriodicalIF":1.0,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147285285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Homology, Recapitulation, and Experimental Embryology: Paths and Meaning of Current Evo-Devo. 同源性、重述和实验胚胎学：当前进化-发展的路径和意义。

IF 1 4区生物学

Zoological Science Pub Date : 2026-02-01 DOI: 10.2108/zs250052

Shigeru Kuratani

{"title":"Homology, Recapitulation, and Experimental Embryology: Paths and Meaning of Current Evo-Devo.","authors":"Shigeru Kuratani","doi":"10.2108/zs250052","DOIUrl":"https://doi.org/10.2108/zs250052","url":null,"abstract":"Evolutionary morphology, including comparative embryology, flourished in the 19th century, epitomized in Haeckel's recapitulation theory. However, it subsequently declined, largely due to accumulating evidence of caenogenesis, while embryology's mainstream gradually shifted toward developmental mechanics-experimental embryology-which laid the foundation for modern developmental biology grounded in reductionist and mechanistic principles. A closer examination of Haeckel's scientific trajectory reveals that, even before formulating the Gastrea theory and the Biogenetisches Grundgesetz (recapitulation theory), he employed siphonophores in what may be regarded as one of the earliest examples of authentic experimental embryology, anticipating many conceptual foundations of contemporary evolutionary developmental biology (Evo-Devo). Despite its innovative contributions, Evo-Devo is not without methodological limitations. One such limitation is highlighted in Sewertzoff's theory of \"secondary Archallaxis,\" logically coherent within the framework of heterochrony, which presupposes an evolutionary process characterized by a persistent search for stable creodes culminating in novel phenotypes-an idea resonant with Waddington's genetic assimilation and Schmalhausen's stabilizing selection. At the same time, the theory underscores the intrinsic difficulty, if not impossibility, of precisely identifying the timing of shifts in developmental programs, a challenge that may constitute a critical vulnerability of the Evo-Devo paradigm. The future advancement of Evo-Devo will depend on the development of methodologies capable of visualizing embryonic developmental pathways and their dynamic transformations.","PeriodicalId":24040,"journal":{"name":"Zoological Science","volume":"43 1","pages":"3-22"},"PeriodicalIF":1.0,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147285216","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Recent Advances in Evolutionary Developmental Biology. 进化发育生物学的最新进展。

IF 1 4区生物学

Zoological Science Pub Date : 2026-02-01 DOI: 10.2108/zsj.43.1

Mikiko Tanaka

引用次数: 0