Early Stages Of Ontogeny Research Articles

Ontogeny of color development in two green-brown polymorphic grasshopper species.

Many insects, including several orthopterans, undergo dramatic changes in body coloration during ontogeny. This variation is particularly intriguing in gomphocerine grasshoppers, where the green and brown morphs appear to be genetically determined (Schielzeth & Dieker, 2020, BMC Evolutionary Biology, 20, 63; Winter etal., 2021, Heredity, 127, 66). A better understanding of how these color morphs develop during ontogeny can provide valuable insights into the evolution and ecology of such a widespread color polymorphism. Here, we focus on the color development of two green-brown polymorphic species, the club-legged grasshopper Gomphocerus sibiricus and the steppe grasshopper Chorthippus dorsatus. By following the color development of individuals from hatching to adulthood, we found that color morph differences begin to develop during the second nymphal stage, are clearly defined by the third nymphal stage, and remain stable throughout the life of an individual. Interestingly, we also observed that shed skins of late nymphal stages are identifiable by color morphs based on their yellowish coloration, rather than the green that marks green body parts. Furthermore, by assessing how these colors are perceived by different visual systems, we found that certain potential predators can chromatically discriminate between morphs, while others may not. These results suggest that the putative genes controlling color morph are active during the early stages of ontogeny, and that green color is likely composed of two components, one present in the cuticle and one not. In addition, the effectiveness of camouflage appears to vary depending on the specific predator involved.

Disturbed by pH? Nacre tablet thickness of freshwater pearl mussels (Margaritifera margaritifera) is a poor temperature proxy

Context The ultrastructure of marine bivalve shells, specifically the thickness of nacre tablets has recently been identified to be related to water temperature. Aims This study investigates whether the nacre tablet thickness (NTT) of freshwater pearl mussel shells can serve as a proxy for stream water temperature. Methods Laboratory-grown juvenile and adult Margaritifera margaritifera from three streams were analysed using scanning electron microscopy to determine the relationship between NTT and water temperature. Key results Neither laboratory-grown juvenile nor adult specimens from the field revealed consistent NTT trends with temperature. Conclusion The NTT of M. margaritifera is largely uncoupled from stream water temperature. Presumably, fluctuations in stream water pH caused physiological stress and forced the animal to allocate more energy to homeostasis than to shell growth. The absence of a coupling between NTT of juvenile mussels and temperature is likely to be due to stronger physiological control on nacre tablet morphology during early stages of ontogeny, favouring thinner tablets with a larger proportion of organics v. CaCO3, which increases the fracture resistance of the shell. Implications Therefore, only if ambient pH remains stable, NTT of freshwater mussels beyond the age of five may serve as a temperature proxy, albeit being associated with a large error.

Stalked eocrinoids attached onto hyolithids with helens from Cambrian Kaili Formation in Jianhe, Guizhou, South China

Reliable fossil record regarding symbiotic relationship is a key to understanding the ecology and environment in Cambrian. Herein, we exhibited an exceptionally well preserved hyolithid with intact stalked eocrinoids attaching on the operculum and conch venter, indicating the symbiotic relationship between hyolithids and eocrinoids. By that we carried out a reconstruction for their epibiotic relationship on the Cambrian sea floor. The ontogenetic features of two eocrinoids on the operculum indicated they were immature (in the early stage of ontogeny). And considering the correlation between the orientation of eocrinoids and the mud flow in event-induced rapid burial, we proposed the orientation of eocrinoids implies the direction of mud flow. Additionally, based on specimens with signs of transport, we found that taphonomical factors besides ecological factors could also lead eocrinoids to preferentially attach on the dorsal or dorso-lateral surface of the conch, which was usually interpreted as a mutualism in previous reports though.

Taxonomy and diversity of slit‐band gastropods (Order Pleurotomariida) and some slit bearing Caenogastropoda from the Pennsylvanian of the USA

AbstractPleurotomariida have the longest fossil record among living gastropods and are diverse and abundant in the middle and upper Palaeozoic. Its traditional classification is based on adult shell characters. The early shell morphology has been largely unknown. We describe exceptionally well‐preserved Pleurotomariida from the Pennsylvanian marine shales of Texas, Oklahoma, Kansas and Ohio. In total, 38 species representing 19 genera are described, including 10 new species, one new genus and one new subgenus:Eirlysella buckhornensisgen. et sp. nov.,Shansiella(Oklahomaella)globilineatasubgen. et sp. nov.,Phymatopleura girtyi,Phymatopleura conica,Worthenia(Yochelsonospira)kuesi,Dictyotomaria turrisbabel,Paragoniozona yanceyi,Spiroscala shwedagoniformis,Peruvispira oklahomaensis,Baylea tenera. Replacement names areParagoniozona ornatanom. nov. (forPleurotomaria asperaGirty),Spiroscala quasipulchranom. nov. (forEuconospira pulchraBatten). The early ontogenetic shells including protoconchs and early teleoconchs are reported in detail for the first time for most taxa. Most species have a protoconch of one whorl as that of living Vetigastropoda. Planktotrophic protoconchs (multi‐whorled larval shells with sinusigera) are reported forPlatyzonaandPeruvispira; they are therefore placed in the family Goniasmatidae (Caenogastropoda). Repaired shell scars were found in juvenile Pleurotomariida specimens (c. 1 mm), suggesting exposure to predation from an early stage of ontogeny. Pleurotomariida are strongly dominant in surface samples of the Finis Shale (Texas) but in bulk samples using fine mesh‐sizes, dominance is much less pronounced, indicating a change in clade proportion depending on sampling method. The taxonomic richness and abundance of Pleurotomariida seen in these Carboniferous shales have not been reported from post‐Triassic formations.

Age‐specific sensitivity of sperm length and testes size to developmental temperature in the bruchid beetle

AbstractIn an era of global warming, the negative effects of temperature stress on fertility could intensify predicted losses of biodiversity. Male fertility is particularly sensitive to temperature stress, yet we have an incomplete understanding of when, during reproductive ontogeny, spermatogenesis is most affected. Here, we used a temperature‐switch protocol to identify when during development temperature affects the expression of sperm length and testes size in the bruchid beetle Callosobruchus maculatus. Egg‐to‐adult development took place at 17°C, 27°C or 33°C for either the full duration of pre‐imago development or it was switched at different stages during development. Full development at 17°C or 33°C resulted in significantly shorter sperm than at 27°C. However, when developing larvae were switched to higher or lower temperatures, we observed switch‐specific phenotypic expression of sperm length and testes size. Our key finding was that sperm length was sensitive to high‐temperature stress during the early stages of ontogeny and to low‐temperature stress during the latter stages of ontogeny. Such age‐specific developmental sensitivity suggests that infertility resulting from transient heat stress (i.e. heatwaves) could be mitigated by age‐related developmental heterogeneity within populations. Those individuals able to avoid severe effects of heat stress on fertility, through serendipitously being at less‐sensitive stages of development, could potentially compensate for the loss of fertility experienced by those individuals at more sensitive stages of development.

Testing for a dietary shift in the Early Cretaceous ceratopsian dinosaur Psittacosaurus lujiatunensis

AbstractMany dinosaurs may have shown ecological differentiation between hatchlings and adults, possibly because of the great size differential. The basal ceratopsian Psittacosaurus lujiatunensis is known from thousands of specimens from the Lower Cretaceous of China and these include many so‐called ‘juvenile clusters.’ During the early stages of ontogeny, P. lujiatunensis underwent a posture shift from quadrupedal to bipedal, and a dietary shift has also been postulated. In this study, we made a 2D mechanical analysis of the jaws of a hatchling and an adult to determine the differences between the two systems; we found some differences, but these were only modest. The adult was better suited to feeding on tough plant material than the hatchling, based on its higher values of absolute and relative bite forces and higher values of mechanical advantage, but there were no substantial shifts in jaw shape or function.

Ontogeny of renin gene expression in the chicken, Gallus gallus

Renin or a renin-like enzyme evolved in ancestral vertebrates and is conserved along the vertebrate phylogeny. The ontogenic development of renin, however, is not well understood in nonmammalian vertebrates. We aimed to determine the expression patterns and relative abundance of renin mRNA in pre- and postnatal chickens (Gallus gallus, White Leghorn breed). Embryonic day 13 (E13) embryos show renal tubules, undifferentiated mesenchymal structures, and a small number of developing glomeruli. Maturing glomeruli are seen in post-hatch day 4 (D4) and day 30 (D30) kidneys, indicating that nephrogenic activity still exists in kidneys of 4-week-old chickens. In E13 embryos, renin mRNA measured by quantitative polymerase chain reaction in the adrenal glands is equivalent to the expression in the kidneys, whereas in post-hatch D4 and D30 maturing chicks, renal renin expressions increased 2-fold and 11-fold, respectively. In contrast, relative renin expression in the adrenals became lower than in the kidneys. Furthermore, renin expression is clearly visible by in situ hybridization in the juxtaglomerular (JG) area in D4 and D30 chicks, but not in E13 embryos. The results suggest that in chickens, renin evolved in both renal and extrarenal organs at an early stage of ontogeny and, with maturation, became localized to the JG area. Clear JG structures are not morphologically detectable in E13 embryos, but are visible in 30-day-old chicks, supporting this concept.

Uncarina roeosliana Rauh ontomorphogenesis in early stages of development

The aim. To find out the morphology of the seeds and the features of its germination and to study the development of Uncarina roeoesliana Rauh (Pedaliaceae) plants in the early stages of ontogeny in connection with the problem of a seed germination and their cultivation under introduction.Materials and methods. The latent and pregenerative periods of the ontomorphogenesis of Uncarina roeoesliana plants under growing conditions in the protected soils of the Botanical garden named after acad. O.V. Fomin were investigated. Biomorphological, introducting, histological methods were used in this work.Results. A method of accelerating the germination of freshly harvested seeds has been developed. Uncarina roeoesliana seeds are large (about 7x5 mm), mostly wide-triangular, brown in colour with little-noticed wing around the perimeter of the seed. The dorsal side forms folds, the hem is on the micropillary part of the seed. The periclinal walls are convex and often with papillae. The embryo is large, occupies most of the seed, the endosperm has a lot of lipids, which is typical for the representative of the same family Sesamum indicum L. The presence of papillae probably contributes to the moisture accumulation to increase the enzymatic activity when the seeds are swell. All of these features of seed germination are consistent with the environmental conditions of Uncarina's natural habitats: high temperatures, low rainfall and significant dry periods. Probably the plants of this species belong to macrobiotics, that is, they can retain seed germination for a long time. The germination is aboveground. During the 24 weeks of development, the plants reach the virginal stage of development: they form radish roots, 5-6 pairs of leaves, of which only two pairs remain in the young plants at this stage, and a thickened basal part of the stem .Conclusions. Comparing Uncarina roeoesliana with other caudiciform plants, we can conclude that this plant has a high potential for survival in arid conditions due to the ability of seeds to germinate only in conditions of considerable moisture and the ability of the plant to accumulate moisture in the basal part of the stem and in fleshy roots. In this case, the plant is adapted to exist both in the mode of a dormancy and in the mode of an active growth, but in the latter case only in the presence of sufficient moisture in the soil

The Capability to Learn and Expression of the Insulin-Like Growth Factor II Gene in the Brain of Male Rats Whose Fathers Were Subjected to Stress Factors in the “Stress–Restress” Paradigm

Abstract—We studied the capability to learn in a passive avoidance task and the rate of its extinction in male rats whose fathers were subjected to stress during the period of spermatogenesis using the “stress–restress” paradigm (a model of post-traumatic stress disorder). In the brain of trained and untrained rats, we studied the expression of genes encoding insulin-like growth factor II and H19, the expression of which is imprinted at the early stages of ontogeny. Experimental males exhibited impaired memory consolidation and accelerated extinction of a passive avoidance response. The expression of Igf2 was decreased in the hippocampus and neocortex of untrained male offspring of stressed fathers. The increased expression of the Igf2 and H19 genes was revealed in the hippocampus of male offspring of control fathers 20 h after training, whereas in the experimental rats, the expression of these genes did not alter. Our data show that the impairment of memory in male offspring of stressed fathers may be mediated by decreased expression of the Igf2 gene.

Effect of social organisation on interspecific differences in overmarking behaviour of foals in African equids.

Overmarking remains an unstudied topic in juvenile mammals. We have previously documented a very high rate of overmarking by foals in four captive African equid species: mountain zebra (Equus zebra), plains zebra (Equus quagga), Grévy's zebra (Equus grevyi), and African wild ass (Equus africanus). African equids vary interspecifically in their social organisation. Since differences in social organisation affect many mammalian behaviours, in this study we investigated interspecific differences in overmarking behaviour of foals, analysing only cases where elimination of any other individual was explored by a foal. We hypothesised that the pattern of overmarking by foals should reflect either differences in social organisation of the species or phylogenetic relations among them. We found that in all species very young foals explored mostly maternal eliminations, and this preference declined with increasing age of the foal and reflected the social organisation of the species; the highest overmarking rate was in species with high intragroup aggression (mountain zebra) and lowest in species with low intragroup aggression and which form crèches (African wild ass). Similarly, the rate of overmarking of the mother, as opposed to other herdmates, was associated with social organisation of the respective species. Thus, we found interspecific differences in overmarking by foals, which were associated with variability in social organisation. Since we also revealed differences between African wild ass and zebra behaviour in early stages of ontogeny, we cannot refute the effect of phylogeny on overmarking behaviour. Additionally, our results supported the identity sharing hypothesis as an explanation of overmarking.

Functional state of an organism of freshwater fish under the influence of abiotic factors

The purpose of the work was to conduct a scientific and experimental analysis of the study of the functional state of the organism of hydrobionts while growing in recirculation of aquaculture systems using an unconventional method of water treatment, which was used in the formation of feed forage for their feeding. The experimental part of the work was carried out on the basis of the laboratory of aquatic bioresources and aquaculture of the Biotechnology Faculty of the Dnipro State Agrarian and Economic University and the Scientific and Experimental Center “Aquatic Biodiversity and Aquaculture of the Pre Dnieper” of the Dniprovsky State Agrarian and Economic University. The practical part of the work consisted of several stages: the formation of the preparatory period (obtaining the breeding culture of phytoplankton and zooplankton, cultivation on different environments in order to establish an optimal scheme); obtaining of fish planting material and determination of fish objects for experiment; staging of the experiment (conducting research on feeding natural food of different processing of mother-crops). Scientific and experimental studies on the study of the functional state of the organism of hydrobionts when cultivated in the PAC with the use of an unconventional method of processing fodder mixed with their feeding give grounds to note the positive impact on its qualitative and functional characteristics. Investigation of the morpho-functional status of blood of freshwater fish on the background of the use of the proposed method for processing fodder mixed with fertilization in the early stages of ontogeny showed that stimulation of erythropoiesis, activation of protein metabolism in the organism of hydrobionts within the limits of the physiological norm occurs in the experimental group. The combination of several rapid methods (GRU) makes it possible to provide comprehensive research and acquires scientific and practical value, since the study of the physiological state of the object of biotesting against the background of the use of various factors involves the implementation of an entire chain of sequential research.

Role of Muscarinic M1, M2, and M3 Receptors in the Regulation of Electrical Activity of Myocardial Tissue of Caval Veins during the Early Postnatal Ontogeny.

We studied the influence of blockers of muscarinic M1, M2, and M3 receptors on the effect of acetylcholine in the myocardial tissue of caval veins in rats at the early stage of ontogeny. The experiments were performed on isolated preparations of the right superior vena cava working under their own rhythm. Action potentials were recorded using the standard microelectrode technique. Acetylcholine (1 μM) suppressed automatic activity in the superior vena cava myocardium. Preliminary perfusion of the preparation with non-selective blocker atropine (1 μM) completely abolished the effect of acetylcholine, treatment with M2 receptor blocker AQ-RA 741 (1 μM) led to partial suppression of the effect of acetylcholine. Blockers of M1 and M3 receptors pirenzepine (1 μM) and 4DAMP (0.1 μM) did not suppress the effect of acetylcholine. Thus, the effect of acetylcholine is predominantly realized via M2 receptors, but M3 receptors can also partially mediate its effect in the superior vena cava myocardium in rats at the early stages of ontogeny.

Побегообразование у некоторых видов калин на ранних этапах онтогенеза

Побегообразование у некоторых видов калин на ранних этапах онтогенеза

The Expression Profile of Connexin-30 and Connexin-32 in the Somatosensory and Visual Cortex of Rats during Early Postnatal Ontogeny

Many studies are focused on the mechanisms of CNS formation, especially on the molecular bases of CNS functioning at different stages of maturation. It is known that functional maturation of different parts of the neocortex occurs at different time points of postnatal ontogeny and gap junctions play an important role in this process. So far, it was not clear whether the expression of major proteins that form gap junctions, connexins, is uniform in the neocortex during its maturation. We compared the dynamics of mRNA level of connexin-30 (Cx30, gjb6) and connexin-32 (Cx32, gjb1) in the somatosensory and visual parts of the neocortex during period of early postnatal ontogeny. We measured the mRNA level of mentioned connexins using quantitative real-time PCR after reverse transcription in the samples of neocortex collected at postnatal days 5, 8, 10, 13, and 20. We found that the level of Cx30 mRNA progressively increased in the somatosensory neocortex from the 5th to 20th day of postnatal ontogeny. In contrast, the level of Cx30 mRNA in the visual cortex began to increase only after the 10th day of postnatal development. Analysis of Cx32 expression showed that its expression started to increase only after 10th day in the somatosensory cortex and after 13th day in the visual cortex. Taken together, our data suggest that the expression of Cx30 and Cx32 is more intense in the somatosensory than in the visual neocortex at early stages of ontogeny which may reflect different time course of maturation of these neocortical areas.

Morphological and histological description of small metoposaurids from Petrified Forest National Park, AZ, USA and the taxonomy of Apachesaurus

ABSTRACTMetoposaurids are Late Triassic temnospondyls that are abundant components of freshwater depositional settings. Although metoposaurids are represented by hundreds of specimens in collections around the world, the vast majority pertain to large-bodied, relatively mature individuals, and as a result, the early stages of ontogeny are still poorly characterised. Small-bodied metoposaurids from North America have traditionally been assigned to Apachesaurus gregorii, interpreted as a diminutive taxon, but this interpretation has not been rigorously tested. Here we provide a morphological description of two new small-bodied metoposaurid specimens from Petrified Forest National Park, AZ, USA. Both provide various anatomical details that improve our understanding of small-bodied metoposaurids and their taxonomic placement within Metoposauridae. Furthermore, we perform a histological analysis on associated intercentra of these specimens, which indicates that these are relatively immature individuals. These findings support the growing consensus that Apachesaurus is a juvenile metoposaurid, thereby providing additional data regarding the early stages of metoposaurid ontogeny and evidence of the persistence of large-bodied forms into the late Norian. Accordingly, these findings merit a reevaluation of the taxonomic validity and diagnosis of the taxon and of the previous interpretations of its paleobiology.

Polymorphism in promoter of SIX4 gene shows association with its transcription and body measurement traits in Qinchuan cattle

The sine oculis homeobox homolog 4 (SIX4) gene belongs to the SIX gene family, which plays a critical role in muscle regeneration and early stages of ontogeny. This study aimed to detect promoter variations of bovine SIX4 genes in Qinchuan cattle, and to evaluate the effect of transcription regulations and body measurement traits. Quantitative real-time PCR (qPCR) results showed that the mRNA expression levels of SIX4 gene were found significantly highest in longissimus thoracis tissue and individual before attaining the stage of physiological maturity. Using sequencing technology on a total of 428 Qinchuan cattle, seven single nucleotide polymorphisms (SNPs) were identified in the promoter region of SIX4, and seven haplotypes representing 18 potential transcription factor compositions of polymorphic potential cis-acting elements. Association analysis indicated that the H3-H3 diplotype performed greater withers height, chest depth, chest circumference, back fat thickness and ultrasound loin muscle area (P < 0.05) than H5-H6, which were consistent with the promoter activity of Hap3 haplotype was higher than the Hap5 and Hap6 haplotype in vitro. These potential transcription factor information and combined genotypes H3-H3 of the SIX4 gene can be used as a molecular marker for selection of economic traits in Qinchuan cattle.

The influence of temperature transfers on subsequent growth of the European peacock butterfly Inachis io (Lepidoptera, Nymphalidae)

The study addresses the effects of higher and lower temperatures experienced during the early stages of ontogeny on the parameters of the subsequent growth and development of the butterfly Inachis io. The caterpillars reared at a temperature of 22°С during instars I–III and then transferred to lower temperatures (16, 18, and 20°C) had higher instantaneous growth rates, larger body mass, and shorter duration of instars IV and V than the caterpillars that developed permanently at these lower temperatures. Vice versa, the caterpillars reared at 16°С during instars I–III and transferred to higher temperatures (18, 20, and 22°C) developed and grew slower than the caterpillars reared at these higher temperatures from the beginning. Possible physiological mechanisms underlying the observed phenomena and their ecological consequences are discussed. Our results are compared with the previously published data on fish—another group of ectothermic organisms, on which similar experiments have been carried out.

Ontogenetic structure features of natural coenotic populations of &lt;i&gt;Medicago cancellata&lt;/i&gt; Bieb. (Fabaceae) in the Samara Zavolzhie

The paper deals with natural populations ontogenetic structure features of Medicago cancellata Bieb. (Fabaceae). It is considered to be a rare representative of Samara flora. The rarity of the species determines the legitimacy of inclusion in the Red Books of the Russian Federation and certain regions. In the Samara Region it is a vulnerable species with a small number of habitats. We studied ontogenetic structure features of the coenotic populations in the Samara Zavolzhie. A total of 33 coenotic populations were studied, population change tendencies and demographic structure features were revealed and a basic ontogenetic spectrum was obtained. It was found that most of the populations of M. cancellata include uneven-aged individuals, being full-term. The structure of species populations is affected by ecological and phytocoenotic conditions of the environment and anthropogenic load. Sprouts and other individuals in the early stages of ontogeny badly need favorable conditions for growth and development. The centered spectrum of populations is formed in conditions of moderate disturbances (grazing, recreation). In case of strong disturbances of communities with participation of a model species (overgrazing, steppe falcons) the maximum of the spectrum shifts to the right. Populations of the species in the Samara Region are very vulnerable, since its habitats are subject to significant anthropogenic press, even in specially protected natural areas.

USING MYCORRHIZA IN ONION GROWING: RUSSIAN EXPERIENCE

The feasibility of using mycorrhizal products in biological agriculture is shown in the paper. When growing onions it is reasonable to use the Glomus fungi. It was found out that the mycorrhiza on onion roots improves the plant growth in the early stages of ontogeny. The effectiveness of mycorrhizal fungi on light-brown soils is reducing under the influence of high temperatures and low humidity. The factors causing the stress reduce the plant immunity and lead to the need to use pesticides.

Формування біомаси на ранніх етапах онтогенезу та урожайність у високопродуктивних сортів озимої пшениці

Формування біомаси на ранніх етапах онтогенезу та урожайність у високопродуктивних сортів озимої пшениці