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Immune genes expressed in Euprymna sp. The shapes in red indicate genes discovered only in E. tasmanica white body. Genes previously reported in E. scolopes are in green. Blue shapes are immune genes identified in both species. Abbreviations are as follows: C3: complement component 3; DMBT1: deleted in malignant brain tumor 1; EFTUD2: elongation factor Tu GTP binding domain containing 2; FGFR2: fibroblast growth factor receptor 2; H2BFQ: histone h2b type 2-e-like; HSP70: heat shock protein 70; IKKγ: Iκβ kinase γ; IRAK4: interleukin-1 receptor-associated kinase 4; LecRK: lectin receptor kinase; LBP1: lipopolysaccharide binding protein 1; LBP2: lipopolysaccharide binding protein 2; LBP3: lipopolysaccharide binding protein 3; MAP2K5: dual specificity mitogen-activated protein kinase kinase 5-like; MACPF: mac/perforin domain containing protein; MyD88: myeloid differentiation primary response 88; NF-κβ1: nuclear factor NF-kappa-β p105 subunit; NOS: nitric oxide synthase; PGRP1: peptidoglycan recognition protein 1; PGRP2: peptidoglycan recognition protein 2; PGRP3: peptidoglycan recognition protein 3; PGRP4: peptidoglycan recognition protein 4; PGRP 5: peptidoglycan recognition 5; REL: proto-oncogene c-Rel; RPS3: Ribosomal protein s3; RPS27a: ubiquitin-40s ribosomal protein s27a; TLR: toll-like receptor;TRAF4: tumor necrosis factor—receptor- associated factor 4-like; TRAF5: tumor necrosis factor- receptor- associated factor 5-like; TRAF6: tumor necrosis factor—receptor- associated factor 6-like.
Source publication
In the mutualistic relationship between the squid Euprymna tasmanica and the bioluminescent bacterium Vibrio fischeri, several host factors, including immune-related proteins, are known to interact and respond specifically and exclusively to the presence of the symbiont. In squid and octopus, the white body is considered to be an immune organ mainl...
Citations
... Genes involved in the activation and production of immune effectors were also affected by CO 2 treatment. In particular, tf coding for transferrin, which sequesters iron so it is unavailable for pathogens and is a key component of the molluscan innate immune response, including in squid [69][70][71][72][73], was upregulated and positively correlated with CO 2 treatment and activity traits in the CNS. The key molecular marker of autophagy, map1l3ca/b, which plays an important role in the molluscan immune response [74][75][76] was downregulated in the CNS. ...
... Elevated CO 2 alters the molluscan immune response, with most research focusing on bivalves [85][86][87][88][89]), though the immune response of an octopus was also affected by elevated CO 2 [90]. Here, we found DE of genes that regulate immune signal transduction pathways and which are also implicated in the molluscan immune response (map4k5/3, syvn1-b, psenen, cbs) [73,[91][92][93]. There were also changes in expression of a range of genes that code for immune effectors, including iron sequestration (tf and cbs), autophagy (map1l3ca/b), controlling the pool of available nucleoside triphosphates (nme6), and phagocytosis ('cell adhesion' and multiple cytoskeleton functional categories). ...
Background
The nervous system is central to coordinating behavioural responses to environmental change, likely including ocean acidification (OA). However, a clear understanding of neurobiological responses to OA is lacking, especially for marine invertebrates.
Results
We evaluated the transcriptomic response of the central nervous system (CNS) and eyes of the two-toned pygmy squid (Idiosepius pygmaeus) to OA conditions, using a de novo transcriptome assembly created with long read PacBio ISO-sequencing data. We then correlated patterns of gene expression with CO2 treatment levels and OA-affected behaviours in the same individuals. OA induced transcriptomic responses within the nervous system related to various different types of neurotransmission, neuroplasticity, immune function and oxidative stress. These molecular changes may contribute to OA-induced behavioural changes, as suggested by correlations among gene expression profiles, CO2 treatment and OA-affected behaviours.
Conclusions
This study provides the first molecular insights into the neurobiological effects of OA on a cephalopod and correlates molecular changes with whole animal behavioural responses, helping to bridge the gaps in our knowledge between environmental change and animal responses.
... Genes involved in the activation and production of immune effectors were also affected by CO 2 treatment. In particular, tf coding for transferrin, which sequesters iron so it is unavailable for pathogens and is a key component of the molluscan innate immune response, including in squid (Herath et al. , 2015;Lambert et al. , 2005;Li et al. , 2019;Ong et al. , 2006;Salazar et al. , 2015), was upregulated and positively correlated with CO 2 treatment and activity traits in the CNS. The key molecular marker of autophagy,map1l3ca/b , which plays an important role in the molluscan immune response (Han et al. , 2019;Moreau et al. , 2015;Picotet al. , 2019) was downregulated in the CNS. ...
... Elevated CO 2 alters the molluscan immune response, with most research focusing on bivalves (Bibby et al. , 2008;Liet al. , 2015;Liu et al. , 2016;Su et al. , 2018;Wuet al. , 2016)), though the immune response of an octopus was also affected by elevated CO 2 (Culler-Juarez & Onthank, 2021). Here, we found DE of genes that regulate immune signal transduction pathways and which are also implicated in the molluscan immune response (map4k5/3, syvn1-b, psenen , cbs ) (Canesiet al. , 2006;De Zoysa et al. , 2010;Goodson et al. , 2005;Salazar et al. , 2015). There were also changes in expression of a range of genes that code for immune effectors, including iron sequestration (tf and cbs ), autophagy (map1l3ca/b ), controlling the pool of available nucleoside triphosphates (nme6 ), and phagocytosis ('cell adhesion' and multiple cytoskeleton functional categories). ...
... Immune-derived factors can also feedback to alter the nervous system and behaviour (Adamo, 2006;Dantzer & Kelley, 2007). Indeed, tf , which is a key component of the molluscan innate immune response (Lambert et al., 2005;Ong et al., 2006;Herath et al., 2015;Salazar et al., 2015;Li et al., 2019) was upregulated and positively correlated with CO 2 treatment and activity traits in the CNS of I. pygmaeus . We also found the expression of genes coding for integrins itga4 and itga9 , cell adhesion molecules playing a key role in invertebrate immune responses (Johansson, 1999;Terahara et al., 2006), were positively correlated in the CNS with CO 2 treatment and activity traits. ...
The nervous system is central to coordinating behavioural responses to environmental change, likely including ocean acidification (OA). However, a clear understanding of neurobiological responses to OA is lacking, especially for marine invertebrates. We evaluated the transcriptomic response of the central nervous system (CNS) and eyes of the two-toned pygmy squid ( Idiosepius pygmaeus ) to OA conditions, using a de novo transcriptome assembly created with long read PacBio ISO-sequencing data. We then correlated patterns of gene expression with CO treatment levels and OA-affected behaviours in the same individuals. OA induced transcriptomic responses within the nervous system related to various different types of neurotransmission, neuroplasticity, immune function and oxidative stress. These molecular changes may contribute to OA-induced behavioural changes, as suggested by correlations between gene expression profiles, CO treatment and OA-affected behaviours. This study provides the first molecular insights into the neurobiological effects of OA on a cephalopod and correlates molecular changes with whole animal behavioural responses, helping to bridge the gap in our knowledge between environmental change and animal responses.
... Genes involved in the activation and production of immune effectors were also affected by CO 2 treatment. In particular, tf coding for transferrin, which sequesters iron so it is unavailable for pathogens and is a key component of the molluscan innate immune response, including in squid (Herath et al., 2015;Lambert et al., 2005;Li et al., 2019;Ong et al., 2006;Salazar et al., 2015), was upregulated and positively correlated with CO 2 treatment and activity traits in the CNS. The key molecular marker of autophagy, map1l3ca/b, which plays an important role in the molluscan immune response (Han et al., 2019;Moreau et al., 2015;Picot et al., 2019) was downregulated in the CNS. ...
... Elevated CO 2 alters the molluscan immune response, with most research focusing on bivalves (Bibby et al., 2008;Liet al., 2015;Liu et al., 2016;Su et al., 2018;Wu et al., 2016)), though the immune response of an octopus was also affected by elevated CO 2 (Culler-Juarez & Onthank, 2021). Here, we found DE of genes that regulate immune signal transduction pathways and which are also implicated in the molluscan immune response (map4k5/3, syvn1-b, psenen , cbs) (Canesi et al., 2006;De Zoysa et al., 2010;Goodson et al., 2005;Salazar et al., 2015). There were also changes in expression of a range of genes that code for immune effectors, including iron sequestration (tf and cbs), autophagy (map1l3ca/b), controlling the pool of available nucleoside triphosphates (nme6 ), and phagocytosis ('cell adhesion' and multiple cytoskeleton functional categories). ...
... Immune-derived factors can also feedback to alter the nervous system and behaviour (Adamo, 2006;Dantzer & Kelley, 2007). Indeed, tf, which is a key component of the molluscan innate immune response (Lambert et al., 2005;Ong et al., 2006;Herath et al., 2015;Salazar et al., 2015;Li et al., 2019) was upregulated and positively correlated with CO 2 treatment and activity traits in the CNS of I. pygmaeus. We also found the expression of genes coding for integrins itga4 and itga9, cell adhesion molecules playing a key role in invertebrate immune responses (Johansson, 1999;Terahara et al., 2006), were positively correlated in the CNS with CO 2 treatment and activity traits. ...
The nervous system is central to coordinating behavioural responses to environmental change, likely including ocean acidification (OA). However, a clear understanding of neurobiological responses to OA is lacking, especially for marine invertebrates. We evaluated the transcriptomic response of the central nervous system (CNS) and eyes of the two-toned pygmy squid ( Idiosepius pygmaeus ) to OA conditions, using a de novo transcriptome assembly created with long read PacBio ISO-sequencing data. We then correlated patterns of gene expression with CO treatment levels and OA-affected behaviours in the same individuals. OA induced transcriptomic responses within the nervous system related to various different types of neurotransmission, neuroplasticity, immune function and oxidative stress. These molecular changes may contribute to OA-induced behavioural changes, as suggested by correlations between gene expression profiles, CO treatment and OA-affected behaviours. This study provides the first molecular insights into the neurobiological effects of OA on a cephalopod and correlates molecular changes with whole animal behavioural responses, helping to bridge the gap in our knowledge between environmental change and animal responses.
... These metabolic networks were also identified through transcriptomics analysis in some previous studies [38][39][40]. Another significant iron soluble non-toxic protein ferritin was found in the metabolic networks of octopus ink, which is involved in the immune system and homeostasis process [41]. Catalase, also found in the ink metabolic network, scavenges free radicals to curtail their damaging effects on the host, and it is a crucial enzyme in antioxidant defense and the innate immune system [42]. ...
The common octopus (Octopus vulgaris) is nowadays the most demanded cephalopod species for human consumption. This species was also postulated for aquaculture diversification to supply its increasing demand in the market worldwide, which only relies on continuously declining field captures. In addition, they serve as model species for biomedical and behavioral studies. Body parts of marine species are usually removed before reaching the final consumer as by-products in order to improve preservation, reduce shipping weight, and increase product quality. These by-products have recently a racted increasing a ention due to the discovery of several relevant bioac-tive compounds. Particularly, the common octopus ink has been described as having antimicrobial and antioxidant properties, among others. In this study, the advanced proteomics discipline was applied to generate a common octopus reference proteome to screen potential bioactive peptides from fishing discards and by-products such as ink. A shotgun proteomics approach by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) using an Orbitrap Elite instrument was used to create a reference dataset from octopus ink. A total of 1,432 different peptides belonging to 361 non-redundant annotated proteins were identified. The final proteome compilation was investigated by integrated in silico studies, including gene ontology (GO) term enrichment, pathways, and network studies. Different immune functioning proteins involved in the innate immune system, such as ferritin, catalase, proteasome, Cu/Zn superoxide dismutase, calreticulin, di-sulfide isomerase, heat shock protein, etc., were found in ink protein networks. Additionally, the potential of bioactive peptides from octopus ink was addressed. These bioactive peptides can exert beneficial health properties such as antimicrobial, antioxidant, antihypertensive, and antitumoral properties and are therefore considered lead compounds for developing pharmacological, functional foods or nutraceuticals.
... It can help identify important immune genes and further study biological immune response mechanisms. Previous researches have carried out transcriptome analyses of aquatic mollusks such as Pinctada martensii (Zhao et al., 2012), Biomphalaria glabrata (Silva et al., 2013), Haliotis diversicolor (Zhang et al., 2018), Octopus vulgaris (Castellanos-Martínez et al., 2014), and Euprymna tasmanica (Salazar et al., 2015;Schultz and Adema, 2017). The transcriptome analyses of A. fangsiao is still lacking, which need a lot of experiments to explore. ...
Immune defense systems are indispensable for living organisms. Within an immune network, problems with any given link can impact the normal life activities of an organism. Amphioctopus fangsiao is a cephalopod that exists widely throughout the world’s oceans. Because of its nervous system and locomotive organs, it has become increasingly studied in recent years. Vibrio anguillarum is one of the most common pathogenic bacteria in aquaculture organisms. It is highly infectious and can infect almost all aquaculture organisms. V. anguillarum infection can cause many adverse biological phenomena, including tissue bleeding. Study the immune response after V. anguillarum infection would help us to understand the molecular mechanisms of immune response in aquaculture organisms. In this research, we infected the primary incubation A. fangsiao with V. anguillarum for 24 h. We analyzed gene expression in A. fangsiao larvae via transcriptome profiles at 0, 4, 12, and 24 h after hatching, and 1,385, 734, and 6,109 differentially expressed genes (DEGs) were identified at these three time points. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were used to identify immune-related DEGs. Protein–protein interaction networks were constructed to examine interactions between immune-related genes. Twenty hub genes involved in multiple KEGG signaling pathways or with multiple protein–protein interaction relationships were identified, and their differential expression verified by quantitative RT-PCR. We first studied V. anguillarum infection of A. fangsiao larvae by means of protein–protein interaction networks. The results provide valuable genetic resources for understanding immunity in molluscan larvae. These data serve as a theoretical basis for the artificial breeding of A. fangsiao.
... Based on cytological differences between these cell types, Claes concluded that they represent different stages of development and proposed a pathway for Hct maturation from a stem cell-like entitythe haemocytoblastto a mature Hct, supporting the haematopoietic function of the WB. 37 Only two molecular studies have been performed on the WB in Euprymna tasmanica 40 and Octopus maya. 41 Based on transcriptomic and gene ontology analysis, Salazar and collaborators identified 8 transcripts with homology to genes involved in haematopoiesis in other organisms, and 16 transcripts involved in the immune response. ...
... 41 Based on transcriptomic and gene ontology analysis, Salazar and collaborators identified 8 transcripts with homology to genes involved in haematopoiesis in other organisms, and 16 transcripts involved in the immune response. 40 Juaŕez and collaborators confirmed the occurrence of haematopoietic transcripts in O. maya WB and the downregulation of immune genes in fertilized females. 41 These results suggest a dual role of the WB in the regulation of the immune system and haematopoiesis. ...
... KEGG annotation using the KAAS annotation tool led to the functional annotation of 21,779 predicted protein sequences, representing 5354 unique K numbers. The low level of annotation of the WB transcriptomes of S. officinalis and other cephalopods 40,41 around 20%revealed a lot of unknown genes. Such a low level of annotation is commonly found in a special model such as the cuttlefish S. officinalis, as already reported for the central nervous system (CNS) transcriptome with only 28%, 59 the accesory nidamental gland with 34% or posterior salivary glands (PSGs) with 45%. ...
Cephalopods, like other Protostomes, lack an adaptive immune system and only rely on an innate immune system. The main immune cells are haemocytes, able to respond to pathogens and external attacks. First reports based on morphological observations suggested that the white body located in the optic sinuses of cuttlefish was at the origin of haemocytes. Combining transcriptomic and proteomic analyses, we identified several factors known to be involved in haematopoiesis in Vertebrate species in cuttlefish white body. Among these factors, members of the JAK-STAT signalling pathway were identified, some of them for the first time in a molluscan transcriptome and proteome. Immune factors such as members of the Toll/NF-κB signalling pathway, pattern recognition proteins and receptors, and members of the oxidative stress responses were also identified, and support an immune role of the white body. Both transcriptome and proteome analyses revealed that the white body harbours an intense metabolism concurrent with the haematopoietic function. Finally, a comparative analysis of the white body and haemocyte proteomes revealed many proteins in common, confirming previous morphological studies on the origin of haemocytes in cuttlefish. This molecular work demonstrates that the white body is multifunctional and provides bases for haematopoiesis regulation in cuttlefish.
... Due to their small size and ease of culturing in captivity, species of Euprymna and Sepiola are increasingly emerging as model systems for a range of biological studies [2][3][4] . The Hawaiian bobtail squid Euprymna scolopes Berry, 1913 has become a prominent model for the study of symbiosis with their luminescent bacteria Vibrio fischeri located in the luminescent organ 5,6 . ...
... Of the other nominal species, the enlarged sucker arrangement in male E. brenneri is most similar to that of E. hoylei Adam, 1986, but this species (in addition to all other nominal Euprymna with the exception of E. brenneri) have 1-3 enlarged finger-like papillae on the proximal end of the hectocotylised arm. Euprymna hoylei, described from the Sulu Archipelago, like E. brenneri, has no enlarged suckers on the second arm, however, E. brenneri males possesses approximately eight very large suckers on the third arm compared to a smaller number described for E. hoylei (3)(4). Female E. hoylei do not have enlarged suckers. ...
Bobtail squid are emerging models for host–microbe interactions, behavior, and development, yet their species diversity and distribution remain poorly characterized. Here, we combine mitochondrial and transcriptome sequences with morphological analysis to describe three species of bobtail squid (Sepiolidae: Sepiolinae) from the Ryukyu archipelago, and compare them with related taxa. One Ryukyuan type was previously unknown, and is described here as Euprymna brenneri sp. nov. Another Ryukyuan type is morphologically indistinguishable from Sepiola parva Sasaki, 1913. Molecular analyses, however, place this taxon within the genus Euprymna Steenstrup, 1887, and additional morphological investigation led to formal rediagnosis of Euprymna and reassignment of this species as Euprymna parva comb. nov. While no adults from the third Ryukyuan type were found, sequences from hatchlings suggest a close relationship with E. pardalota Reid, 2011, known from Australia and East Timor. The broadly sampled transcriptomes reported here provide a foundation for future phylogenetic and comparative studies. Gustavo Sanchez et al. describe three species of bobtail squid from the Ryukyu archipelago using morphological analysis, mitochondrial sequences, and transcriptome sequences. One of these species was a previously unknown bobtail squid from the genus Euprymna, the second is reassigned to the genus Euprymna, and the third species is closely related to another bobtail squid endemic from Australia and East Timor.
... Due to the lack of an annotated genome the use of an RNA-seq approach might improve the knowledge of their gene at sequences and expression level. There are only few studies focused on RNA-seq to evaluate the gene expression profiles in cephalopods and even less if we focused on the genus Octopus [23][24][25][26][27] . The combination of that approach with a proteome analyses can synergistically strengthen our understanding of common octopus paralarvae. ...
Common octopus, Octopus vulgaris, is an economically important cephalopod species. However, its rearing under captivity is currently challenged by massive mortalities previous to their juvenile stage due to nutritional and environmental factors. Dissecting the genetic basis and regulatory mechanism behind this mortality requires genomic background knowledge. A transcriptomic sequencing of 10 dph octopus paralarvae from different experimental conditions was constructed via RNA-seq. A total of 613,767,530 raw reads were filtered and de novo assembled into 363,527 contigs of which 82,513 were annotated in UniProt carrying also their GO and KEGG information. Differential gene expression analysis was carried out on paralarvae reared under different diet regimes and temperatures, also including wild paralarvae. Genes related to lipid metabolism exhibited higher transcriptional levels in individuals whose diet includes crustacean zoeas, which had an impact over their development and immune response capability. High temperature induces acclimation processes at the time that increase metabolic demands and oxidative stress. Wild individuals show an expression profile unexpectedly similar to Artemia fed individuals. Proteomic results support the hypothesis revealed by transcriptional analysis. The comparative study of the O. vulgaris transcriptomic profiles allowed the identification of genes that deserve to be further studied as candidates for biomarkers of development and health. The results obtained here on the transcriptional variations of genes caused by diet and temperature will provide new perspectives in understanding the molecular mechanisms behind nutritional and temperature requirements of common octopus that will open new opportunities to deepen in paralarvae rearing requirements.
... A gene expression study of the white body from Euprymna tasmanica also revealed a number of potential genes involved with hematopoiesis (Salazar, Joffe, Dinguirard, Houde, & Castillo, 2015). Future studies will focus on whether hematopoiesis in the E. scolopes white body is influenced by bacteria or other environmental cues. ...
The binary association between the squid, Euprymna scolopes, and its symbiont, Vibrio fischeri, serves as a model system to study interactions between beneficial bacteria and the innate immune system. Previous research demonstrated that binding of the squid's immune cells, hemocytes, to V. fischeri is altered if the symbiont is removed from the light organ, suggesting that host colonization alters hemocyte recognition of V. fischeri. To investigate the influence of symbiosis on immune maturation during development, we characterized hemocyte binding and phagocytosis of V. fischeri and nonsymbiotic Vibrio harveyi from symbiotic (sym) and aposymbiotic (apo) juveniles, and wild‐caught and laboratory‐raised sym and apo adults. Our results demonstrate that while light organ colonization by V. fischeri did not alter juvenile hemocyte response, these cells bound a similar number of V. fischeri and V. harveyi yet phagocytosed only V. harveyi. Our results also indicate that long‐term colonization altered the adult hemocyte response to V. fischeri but not V. harveyi. All hemocytes from adult squid, regardless of apo or sym state, both bound and phagocytosed a similar number of V. harveyi while hemocytes from both wild‐caught and sym‐raised adults bound significantly fewer V. fischeri, although more V. fischeri were phagocytosed by hemocytes from wild‐caught animals. In contrast, hemocytes from apo‐raised squid bound similar numbers of both V. fischeri and V. harveyi, although more V. harveyi cells were engulfed, suggesting that blood cells from apo‐raised adults behaved similarly to juvenile hosts. Taken together, these data suggest that persistent colonization by the light organ symbiont is required for hemocytes to differentially bind and phagocytose V. fischeri. The cellular immune system of E. scolopes likely possesses multiple mechanisms at different developmental stages to promote a specific and life‐long interaction with the symbiont.
... In cephalopods, it is well known that haemocytes are originated within the WB, in fact, several hematopoiesis genes were found to be expressed in the WB of squid Euprymna tasmanica [8]. In addition, transcripts associated with immune-related signal transduction pathways were found, as well as other genes of the immune response previously identified in E. scolopes [9]. ...
... Herein, to better understand the WB functions, this study was directed to describe its gene expression, with emphasis in sex-related and reproductive-stage related differences via RNA-Seq. This technology has been successfully implemented for gene discovery and for estimation of gene expression levels in different cephalopod tissues [8,[17][18][19][20][21]. In addition, different tissues were compared in terms of gene expression to identify sex-specific and tissue-specific transcripts. ...
... These results suggest that the WB plays a role in the glucocorticoid metabolism, and in the response to glucocorticoids. In this regard, the WB can be an important target of glucocorticoids, considering that these molecules can restrain the immune and inflammatory responses [79][80][81][82][83], which are mediated by the WB at least partially [8,84]. But why the immune response should be down-regulated? ...
White bodies (WB), multilobulated soft tissue that wraps the optic tracts and optic lobes, have been considered the hematopoietic organ of the cephalopods. Its glandular appearance and its lobular morphology suggest that different parts of the WB may perform different functions, but a detailed functional analysis of the octopus WB is lacking. The aim of this study is to describe the transcriptomic profile of WB to better understand its functions, with emphasis on the difference between sexes during reproductive events. Then, validation via qPCR was performed using different tissues to find out tissue-specific transcripts. High differentiation in signaling pathways was observed in the comparison of female and male transcriptomic profiles. For instance, the expression of genes involved in the androgen receptor-signaling pathway were detected only in males, whereas estrogen receptor showed higher expression in females. Highly expressed genes in males enriched oxidation-reduction and apoptotic processes, which are related to the immune response. On the other hand, expression of genes involved in replicative senescence and the response to cortisol were only detected in females. Moreover, the transcripts with higher expression in females enriched a wide variety of signaling pathways mediated by molecules like neuropeptides, integrins, MAPKs and receptors like TNF and Toll-like. In addition, these putative neuropeptide transcripts, showed higher expression in females’ WB and were not detected in other analyzed tissues. These results suggest that the differentiation in signaling pathways in white bodies of O. maya influences the physiological dimorphism between females and males during the reproductive phase.
