Student works after the second‑year practice

Student works after II-year practice - 2008 Student works after II-year practice - 2009 Student works after II-year practice - 2011 Student works after II-year practice - 2012 (Part I) Student works after II-year practice - 2012 (Part II) Student works after II-year practice - 2013 Student works after II-year practice - 2014 Student works after II-year practice - 2015 Student works after II-year practice - 2016 Student works after II-year practice - 2017 STUDY OF CORRESPONDENCES BETWEEN STAGES OF HIND LIMB DEVELOPMENT AND ORAL APPARATUS IN THE NORMAL DEVELOPMENT OF GREEN FROG TADPOLES Afonycheva Ya. V., Bondareva A. A., Balanyuk E. V., BIBIK Yu. S. Kharkiv National University named after V.N. Karazin, Faculty of Biology, 4 Svobody Square, Kharkiv, Ukraine During the normal development of green frog (Pelophylax esculentus complex) tadpoles, the same stages of hind‑limb development may correspond to different types of oral apparatus. This can be explained by two alternative hypotheses: (1) a given stage of hind‑limb development corresponds to several “sub‑stages” differing in oral‑apparatus structure; (2) each tadpole possesses a characteristic oral‑apparatus type that it retains throughout limb development. We performed an experiment to test these hypotheses. For the experiment we used tadpoles caught on the left bank of the Seversky Donets River downstream of Zmiev, Kharkiv region. From the caught tadpoles we formed pairs with identical hind‑limb development (stages 2–7; see theses by T. Vinogradska and others in this volume) and identical oral apparatus types (A and D; see theses by Yu. BIBIK in this volume). We kept 15 pairs of tadpoles in containers with 330 ml of water for 6 days. Water was changed daily and tadpoles were fed an excess of dry aquarium food. The first hypothesis would be supported by a result in which oral‑apparatus types changed more frequently (or at least as fast) as limb‑development stages. The second hypothesis would be supported by changes in limb stages while oral apparatuses remained unchanged. At the start of the experiment the A‑type oral apparatus was recorded only in tadpoles at relatively early stages (all four tadpoles at stage 2 of hind‑limb development and 2 of 16 tadpoles at stage 4). During the experiment these tadpoles changed from type A to D (except one that died and one that was injured). All 24 tadpoles with type D oral apparatus, occupying stages 3–7, retained their oral apparatus unchanged. Hind‑limb development in most tadpoles advanced by one–two stages. The most intensive limb growth occurred in stage 4 tadpoles (in some individuals development advanced by three–four stages), although in tadpoles that changed oral apparatus the hind limb did not change. Thus we recorded two processes: (1) hind‑limb development from early to later stages proceeding at different rates; (2) remodeling of the oral apparatus from type A to D (occurring at different limb‑development stages in different individuals). Importantly, the change of oral‑apparatus type proceeds in one direction and only at relatively early limb‑development stages. This result does not fully match either tested hypothesis, although it is closer to the second. Apparently, the characteristic oral‑apparatus type for each tadpole is not formed immediately but passes through several stages in early development. Summary. It has been investigated hind limbs and oral apparatus development character in the course of normal ontogenesis of water frogs tadpoles to examine the fits between certain stages of hind limbs development and the types of oral apparatus. According to the results of our experiment it has been suggested that the kind of oral apparatus which is typical for each tadpole is not formed at once but it passes several phases in the early stages of development. The described experiment was carried out during the UIRS in the vertebrate zoology practicum. The authors thank Assoc. Prof. D.A. Shabanov for supervision of this work. Afonycheva Ya. V., Bondareva A. A., Balanyuk E. V., BIBIK Yu. S. Study of correspondences between hind‑limb development stages and oral apparatuses during normal development of green frog tadpoles. // “Biology: from molecule to biosphere”. Materials of the V International Conference of Young Scientists. – Kharkiv: Operational Polygraphy, 2010. – pp. 337‑338.

DIFFERENCES IN PROPORTIONS AND SIZES OF GREEN FROG TADPOLES DEVELOPING AT DIFFERENT TIMES Belkina I. O., Brileva O. P. Kharkiv National University named after V.N. Karazin, Faculty of Biology, 4 Svobody Square, Kharkiv, Ukraine European green frogs (Pelophylax esculentus complex) constitute an interesting study group in which interspecific hybridisation, polyploidy and semi‑clonal inheritance occur. To study factors influencing the composition of green‑frog population systems, it is necessary to examine tadpole development under natural conditions. We studied three samples of tadpoles collected on the left bank of the Seversky Donets River downstream of Zmiev: sample 1 (24 June 2010) comprised 130 tadpoles, sample 2 (1 July 2010) – 232 tadpoles, sample 3 (10 July 2010) – 139 tadpoles. Body length and trunk length were measured with a caliper (accuracy 0.1 mm); weight was measured with electronic scales (accuracy 0.001 g). Tadpole developmental stages were determined by hind‑limb morphology using a stereomicroscope (see Vinogradska et al. theses in this volume). Data were processed with Statistica for Windows 6.5. We found that tadpoles developing later have relatively longer trunks (Fig. 1). ANOVA (considering collection date and developmental stage effects on relative body length) showed a highly significant difference between samples (p < 0.000001). [IMG_1] Fig. 1. Relative trunk length (trunk length / total body length) of tadpoles from three samples collected at different times. The abscissa shows hind‑limb developmental stages. At the same developmental stages, tadpoles from different samples differ much less in total body length and virtually not in weight. The observed result could be due to a systematic measurement error in trunk length for some samples, but the authors consider this unlikely and plan to re‑examine the data in the next field season. Thus, tadpoles developing at different times differ in proportions, with trunk elongation being compensated by a more “slender” body, so that weight changes only slightly. Summary. At comparison of tadpoles of the green frogs caught at various times (on July, 24th, on July, 1st and on July, 10th 2010) differences in their proportions are registered. At tadpoles which educe later, the attitude of length of a trunk to body total length significantly increases. The results were obtained during a student‑research project in the vertebrate zoology practicum. The authors thank Yu. S. BIBIK for assistance and Assoc. Prof. D.A. Shabanov for scientific supervision. Belkina I. O., Brileva O. P. Differences in proportions and sizes of green frog tadpoles developing at different times. // “Biology: from molecule to biosphere”. Materials of the V International Conference of Young Scientists. – Kharkiv: Operational Polygraphy, 2010. – pp. 341‑342.

WHAT FACTORS DETERMINE THE TYPE OF ORAL APPARATUS IN GREEN FROG TADPOLES? BIBIK Yu. S. Kharkiv National University named after V.N. Karazin, Faculty of Biology, 4 Svobody Square, Kharkiv, Ukraine. e‑mail: yulia.bibik@gmail.com The hybrid complex of European green frogs (Pelophylax esculentus complex) consists of two parental species and several semi‑clonal hybrid forms. Developmental features of tadpoles of different green‑frog forms are still scarcely described. We studied tadpoles from seven samples. Samples 1 and 2 were collected on the left bank of the Seversky Donets River downstream of Zmiev on 24 June and 1 July 2010, respectively. Samples 3 and 4 were reared from egg clutches collected on 6 May 2010 in the Seversky Donets floodplain near the HNU biological station, and sample 5 was obtained from a pair of frogs (female Pelophylax ridibundus, male P. esculentus) caught at the same site. Likely, samples 1‑5 contained both P. ridibundus and P. esculentus. Samples 6 and 7 were collected on 18 June 2010 in Donetsk region, from water bodies inhabited exclusively by P. ridibundus. Formalin‑fixed tadpoles were examined under a stereomicroscope, oral‑apparatus type was recorded (Fig. 1) and hind‑limb developmental stage was determined (see Vinogradska et al. in this volume). Results of oral‑apparatus typing are presented in Table 1. [IMG_2] Fig. 1. Classification of oral‑apparatus types of green frog tadpoles (schematic arrangement of clasping keratin plates) Table 1. Diversity of oral‑apparatus types in the studied tadpole samples Samples Number Hind‑limb stages Oral‑apparatus types A B C D E F G H I 1 and 2 352 1–10 0 0 0 31 0 16 242 5 58 3–5 419 1–8 81 18 30 216 12 14 48 0 0 6 and 7 96 2–8, 10 0 0 0 0 0 0 82 0 14

Samples Number Hind‑limb stages Oral‑apparatus types A B C D E F G H I 1 and 2 352 1–10 0 0 0 31 0 16 242 5 58 3–5 419 1–8 81 18 30 216 12 14 48 0 0 6 and 7 96 2–8, 10 0 0 0 0 0 0 82 0 14

EFFECT OF GROUPING ON THE DEVELOPMENT OF GREEN FROG TADPOLES BIBIK Yu. S., Kovalenko M. S., Kuchkova A. G. Kharkiv National University named after V.N. Karazin, Faculty of Biology, 4 Svobody Square, Kharkiv, Ukraine. e‑mail: yulia.bibik@gmail.com The aim of this work is to determine whether belonging to a mixed‑age group influences the development of oral apparatuses and limbs in tadpoles of Pelophylax esculentus complex. As shown (Mina, Klevzel, 1976), group housing of aquatic animals alters their ontogeny compared with solitary rearing. We used tadpoles from the Seversky Donets River collected on the left bank downstream of Zmiev on 24 June 2010. Observing live tadpoles under a stereomicroscope, we selected two groups with identical hind‑limb morphology. Twenty‑four “small” tadpoles were at limb stage 3, twelve “large” at stage 7. Both groups contained tadpoles with oral‑apparatus types G, D, H and I (see BIBIK theses). Tadpoles were weighed and placed in half‑liter jars containing 0.3 l of river water. Six containers received one “small” tadpole each, six received one “large” tadpole each, and another six received three “small” and one “large” tadpole. Water was changed daily and tadpoles were fed excess dry aquarium food. After 10 days we re‑measured mass, determined limb stages and oral‑apparatus types. In “small” solitary tadpoles limb stages progressed from 3 to 6, whereas in groups they progressed from 3 to 4. In “large” tadpoles, regardless of housing, stages advanced from 7 to 9. Group housing significantly (p = 0.004) reduced relative mass gain in both groups, similarly for “large” and “small” tadpoles. Thus, grouping slowed growth (as measured by mass increase) in both groups, while limb development (as assessed by limb condition) was inhibited only in “small” tadpoles. The oral‑apparatus type in “small” tadpoles changed significantly more often (Mann‑Whitney p = 0.005) than in “large” ones. Grouping did not affect the frequency of oral‑apparatus changes in “large” tadpoles and reduced it only slightly (p = 0.32) in “small” ones. In “small” tadpoles the following initial→final oral‑apparatus transitions were recorded: D→D (13); D→E (1); D→G (3); G→G (2); G→H (2); H→H (1); I→G (2). In “large” tadpoles the transitions were: G→G (2); G→H (5); G→reduction of oral apparatus (5). The latter group resembles metamorphic events (when the clasping oral apparatus is reduced and a predatory apparatus develops), but these processes occur at later developmental stages. Summary. Development of hind limbs and oral apparatus as well as mass growth have been studied in small and big tadpoles of water frogs (Pelophylax esculentus complex) maintained solitary or in groups (1 big and 3 small tadpoles in each group). Maintenance in groups inhibits growth both in small and big tadpoles, whereas hind limbs development is inhibited only in small tadpoles. Alteration of structure in various types of oral apparatus is also described. The experiment was performed as a student‑research project during the II‑year practicum. The authors thank Assoc. Prof. D.A. Shabanov for scientific supervision of this work. BIBIK Yu. S., Kovalenko M. S., Kuchkova A. G. Effect of group effect on the development of green frog tadpoles. // “Biology: from molecule to biosphere”. Materials of the V International Conference of Young Scientists. Kharkiv: Operational Polygraphy, 2010. – pp. 338‑339.

GROWTH AND DEVELOPMENT OF GREEN FROG TADPOLES IN NATURAL HABITAT Vinogradska T. I., Tolokneyeva A. A., Komarova E. V., Khloponina V. V., BIBIK Yu. S. Kharkiv National University named after V.N. Karazin; 4 Svobody Square, Kharkiv, Ukraine European green frogs (Pelophylax esculentus complex) form a hybridogenic complex that attracts many researchers (Shabanov, Lytvynchuk, 2010). For a comprehensive study of this group it is necessary to establish how their ontogeny proceeds, including larval development. After describing the development of mixed tadpole samples taken from natural GPS, we will be able to compare larval development of individual frog forms. We studied tadpoles collected on the left bank of the Seversky Donets downstream of Zmiev among aquatic vegetation in shallow water. Sample 1, collected on 24 June 2010, comprised 130 individuals; sample 2, collected on 1 July 2010, comprised 232 individuals. Growth measures were total body length with tail and trunk length (measured with a caliper to 0.1 mm) and weight (measured with electronic scales to 0.001 g). Developmental stages were determined by hind‑limb condition. The following stages were distinguished: 1) no limbs; 2) limb buds appear as rounded protuberances; 3) limb buds begin to curve; 4) distal limb end forms a blade; 5) three‑finger buds; 6) four‑finger buds; 7) five‑finger buds, knee joint begins to form; 8) knee joint formed; 9) knee joint and joint between tibia and fibula formed, membranes between three fingers; 10) fully formed inter‑digital membrane. Data were processed with Statistica for Windows 6.5. Overall, the recorded relationship between length (L, mm) and weight (W, g) of tadpoles can be extrapolated by the equation W = 0.26 – 0.27 × L + 0.098 × L. Length and weight values for individual stages are shown in Table 1. Table 1. Mean length and weight of tadpoles at different developmental stages

Stage Number of individuals (samples 1 + 2) Length (L), mm Weight (W), g 1 4 + 24 2.02 0.107 2 37 + 74 2.74 0.265 3 23 + 22 3.24 0.408 4 5 + 12 3.84 0.657 5 7 + 29 3.88 0.659 6 22 + 20 4.22 1.000 7 19 + 8 4.76 1.261 8 11 + 17 5.30 1.698 9 1 + 11 5.52 1.788 10 1 + 15 6.42 2.597{"translated_text":"As can be seen from Table 1, the samples differ in the relative abundance of tadpoles at different developmental stages. When comparing the observed distribution with the theoretical one, constructed on the assumption of no association between the sample and developmental stage, Pearson's chi‑square = 34.4, which for the given degrees of freedom corresponds to highly significant differences (p = 0.000075). The predominance of late‑stage tadpoles in sample No. 2 is probably related to a longer period of their development.\n\nSummary. Described stage of the development of the hind limbs of water frog (Pelophylax esculentus complex). The studied polliwogs were caught in the Severskiy Donets River in the vicinity of Zmiev. The dependence of the weight (W) of polliwogs on their body length (L) is of the form W = 0.26 – 0.27 L + 0.098 L².\nThe described results were obtained during a teaching‑research work in the vertebrate zoology practicum. The authors express gratitude to Assoc. Prof. D. A. Shabanov for supervising this work.\n\nVinogradska T. I., Toloknyeva A. A., Komarova E. V., Khloponina V. V., BIBIK Yu. S. Growth and development of tadpoles of green frogs in their natural habitat // \"Biology: from molecule to biosphere\". Materials of the V International Conference of Young Scientists. – Kharkiv: Operatyvna Polihrafiya, 2010. pp. 344‑345.\nSTUDY OF FLUCTUATING ASYMMETRY OF COLOURING IN GREEN FROGS\nKryshchal O. A., Matasova E. V.\nKharkiv National University named after V.N. Karazin, Faculty of Biology, Svobodi Square, 4, Kharkiv, Ukraine\nDetermination of the level of fluctuating asymmetry, FA (random deviations from bilateral symmetry) – one of the methods for assessing ontogenetic stability. Development in interspecific hybrids is usually less stable than in parental species. In the vicinity of the HNU biostation in the village of Haidary (Zmiiv district, Kharkiv region) among European green frogs live representatives of the parental species, Pelophylax ridibundus (lake frogs) and hemiclonal interspecific hybrids, Pelophylax esculentus (edible frogs). In 2008 the FA of their colouration was studied using commonly accepted traits – asymmetry of the dorsomedial stripe, number of spots on the back and spot‑stripes on the hind limbs (Deryazhenkova et al., 2008). Strangely, the FA of hybrids in this study did not exceed the FA of the parental species. We applied a new method for measuring FA in frogs, assuming it would be more sensitive to deviations from colour symmetry.\nIn the floodplain of the Seversky Donets River near the village of Haidary, 186 green frogs were captured. They were identified by external traits: low and sloping heel tubercle, absence of a yellowish hue on the thighs, dark vocal sacs in males correspond to P. ridibundus; high tubercle, presence of a yellow hue on the thighs, light vocal sacs in males correspond to P. esculentus. We identified 107 individuals (46 females, 36 males and 25 subadults) as P. esculentus, 55 individuals (31 + 12 + 12 respectively) as P. ridibundus, and 24 individuals (12 + 6 + 6) remained unidentified due to an atypical combination of traits.\nThe dorsal side of the body and limbs of each frog was photographed (for this the frog was made to grasp a support with its forelimbs and was stretched lengthwise by the toes of the hind limbs), after which it was released at the capture site. In CorelDraw a grid was overlaid on each photograph, dividing it along the frog’s body axis, from snout to heel tubercles, into 20 zones. For all zones where possible, colouration was classified as symmetric (S), slightly asymmetric (H) or strongly asymmetric (A). The numbers of zones of each type – NS, NH and NA – were counted. Results were processed in Statistica. Individual asymmetry was calculated as FA = (NA + NH/2) / NS.\nFA traits that take the sign of deviation from symmetry into account have a normal distribution with a mean of 0. Our FA measure takes only positive values. The most frequent values were close to 0; as the FA index increased, the frequency of values decreased. This distribution confirms that the used measure characterises FA and can be applied to study developmental stability in frogs and probably some other animals. P. esculentus proved significantly (Mann‑Whitney p = 0.031) more asymmetric than P. ridibundus. The median of the used FA measure for P. esculentus is 0.4, for P. ridibundus – 0.33, and for unidentified individuals – 0.39. The influence of sex and age on colour FA was not significant.\nSummary. For the study of fluctuating asymmetry (FA) in water frogs, individuals were photographed from the dorsal side. Photography divided the body axis into 20 zones. We counted symmetrical, weakly and strongly asymmetrical zones. The colouration of hybrids of water frogs P. esculentus was found to be more asymmetrical than that of representatives of the parental species water frogs P. ridibundus.\nThe work was performed as a UIRS during the vertebrate zoology practicum. The authors thank Assoc. Prof. D. A. Shabanov for the idea of the work and scientific supervision.\nKryshchal O. A., Matasova E. B. Study of fluctuating asymmetry of colouration in green frogs. // \"Biology: from molecule to biosphere\". Materials of the V International Conference of Young Scientists. – Kharkiv: Operatyvna Polihrafiya, 2010. pp. 355‑356."}

{ "translated_text": "B\n\nC\n\nD\n\nE\n\nF\n\nG\n\nH\n\nI\n\n1 and 2\n\n352\n\n1–10\n\n0\n\n0\n\n0\n\n31\n\n0\n\n16\n\n242\n\n5\n\n58\n\n3–5\n\n419\n\n1–8\n\n81\n\n18\n\n30\n\n216\n\n12\n\n14\n\n48\n\n0\n\n0\n\n6 and 7\n\n96\n\n2–8, 10\n\n0\n\n0\n\n0\n\n0\n\n0\n\n0\n\n82\n\n0\n\n14\n\nSamples 3-5, developed under identical conditions but presumably differing in genotype, differed significantly in the ratios of the seven registered types of oral apparatuses (χ² criterion p<0.00001). Apparently, the diversity of oral apparatuses reflects the genotypic features of the frogs. In samples 1 and 2, obtained from natural habitats, types A, B, C and E were not found, but types H and I were present. Finally, in samples 6 and 7, consisting only of tadpoles of Pelophylax ridibundus, only two types of oral apparatuses were recorded: G and I. The lowest diversity of oral apparatus types is characteristic of single-species samples from natural habitats, and the highest for mixed samples developed in artificial conditions. Thus, the diversity of tadpole oral apparatuses is influenced by species, genotype, and developmental conditions, but none of these factors alone can fully explain the observed variability of their oral apparatuses.\nSummary. The classification of types of scrape oral apparatuses of water frog tadpoles (Pelophylax esculentus complex) has been developed. The variety of oral apparatuses types has been described in a few selections of tadpoles. Species, genotype and conditions of tadpoles development influence on the oral apparatus structure. The complete explanation of observed picture of oral apparatus mutability was not successful.\nThe author thanks T. Vinogradska, N. Tolokneev, E. Komarova and V. Khloponina for assistance in the work, and associate professor D. A. Shabanov for scientific supervision.\nBibik Yu.S. Which factors determine the type of oral apparatus of green frog tadpoles? // \"Biology: from molecule to biosphere\". Materials of the V International Conference of Young Scientists. - Kharkiv: Operatyvna Polihrafia, 2010. - p. 339-340.\nTHE INFLUENCE OF GROUP EFFECT ON THE DEVELOPMENT OF GREEN FROG TADPOLES\nBibik Yu. S., Kovalenko M. S., Kuchkova A. G.\nKharkiv National University named after V.N. Karazin, Faculty of Biology, Svobody Square, 4, Kharkiv, Ukraine. e-mail: yulia.bibik@gmail.com\nThe task of this work is to determine whether belonging to a mixed-age group affects the development of oral apparatuses and limbs of tadpoles of the Pelophylax esculentus complex. As known (Mina, Klevezal, 1976), group housing of aquatic animals alters their ontogeny compared with solitary rearing.\nWe used tadpoles from the Seversky Donets River, collected on the left bank downstream of Zmiev on 24.06.2010. Observing live tadpoles under a stereoscopic microscope, we selected two groups with identical hind‑limb structure. Twenty‑four \"small\" tadpoles were at stage 3 of limb development (see Vinogradska et al. theses), 12 large ones at stage 7. Both groups included tadpoles with oral apparatus types (see Bibik theses) G, D, H and I. Tadpoles were weighed and placed in containers (half‑liter jars) containing 0.3 L of river water. In six containers we placed one \"small\" tadpole, in six – one \"large\", and in another six – three \"small\" and one \"large\". Water was changed daily and tadpoles were fed excess dry aquarium food. After 10 days we re‑measured mass, determined limb development stages and oral apparatus types.\nIn \"small\" solitary tadpoles limb stages progressed from 3 to 6, whereas in groups from 3 to 4. In \"large\" tadpoles, regardless of housing, stages advanced from 7 to 9. Group housing significantly (p=0.004) reduced relative mass gain in both groups, almost equally for \"large\" and \"small\". Thus, group housing slowed growth (assessed by mass increase) in both groups, and limb development (assessed by limb condition) only in \"small\" tadpoles.\nThe oral apparatus type in \"small\" tadpoles changed significantly (Mann‑Whitney p=0.005) more often than in \"large\" ones. Group housing did not affect the frequency of oral apparatus type changes in \"large\" tadpoles and insignificantly (p=0.32) reduced it in \"small\" ones. In \"small\" tadpoles the following initial→final oral apparatus combinations were recorded: D→D (13 cases); D→E (1); D→G (3); G→G (2); G→H (2); H→H (1); I→G (2). For \"large\" tadpoles the combinations were: G→G (2 cases); G→H (5); G→reduction of oral apparatus (5). The latter group resembles events occurring during metamorphosis (when the scraping oral apparatus is reduced and a predatory apparatus develops), but these processes occur at later developmental stages.\nSummary. Development of hind limbs and oral apparatus as well as mass growth have been studied in small and big tadpoles of water frogs (Pelophylax esculentus complex) maintained solitary or in groups (1 big and 3 small tadpoles in each group). Maintenance in groups inhibits growth both in small and big tadpoles, whereas hind‑limb development is inhibited only in small tadpoles. Alteration of structure in various types of oral apparatus is also described.\nThe described experiment was performed as a teaching‑research work during the second‑year zoology practicum. The authors thank associate professor D. A. Shabanov for scientific supervision of this work.\nBibik Yu. S., Kovalenko M. S., Kuchkova A. G. The influence of group effect on the development of green frog tadpoles. // \"Biology: from molecule to biosphere\". Materials of the V International Conference of Young Scientists. Kharkiv: Operatyvna Polihrafia, 2010. - p. 338-339.\nGROWTH AND DEVELOPMENT OF GREEN FROG TADPOLES IN NATURAL HABITAT\nVinogradska T. I., Tolokneeva A. A., Komarova E. V., Khloponina V. V., Bibik Yu. S.\nKharkiv National University named after V.N. Karazin; Svobody Square, 4, Kharkiv, Ukraine\nEuropean green frogs (Pelophylax esculentus complex) constitute a hybridogenic complex that attracts many researchers (Shabanov, Lytvynchuk, 2010). For comprehensive study of this group it is necessary to establish how their ontogeny proceeds, including larval development. After describing the development of mixed tadpole samples taken from natural GPS, it will be possible to compare larval development features of individual frog forms.\nWe studied tadpoles collected on the left bank of the Seversky Donets downstream of Zmiev in aquatic vegetation on shallow water. Sample No 1, collected on 24 June 2010, consists of 130 individuals; sample No 2, collected on 1 July 2010, of 232 individuals.\nGrowth measures were total body length with tail and trunk length (measured with calipers to 0.1 mm) and weight (measured with electronic scales to 0.001 g). Developmental stages were determined by hind‑limb condition. The stages were: 1) no limbs; 2) limb buds appear as rounded protuberances; 3) limb buds begin to bend; 4) distal limb end forms a blade; 5) three‑finger buds; 6) four‑finger buds; 7) five‑finger buds, knee joint begins to develop; 8) knee joint formed; 9) knee joint and joint between tibia and fibula formed, webbing between three fingers; 10) fully formed interdigital webbing. Data were processed with Statistica for Windows 6.5.\nOverall, the recorded relationship between length (L, mm) and weight (W, g) of tadpoles can be extrapolated by the equation W = 0.26 – 0.27 × L + 0.098 × L². Length and weight values for individual stages are shown in Table 1.\nTable 1. Mean length and weight of tadpoles at different developmental stages\n\nStage\nNumber of individuals (samples 1+2)\nLength (L), mm\nWeight (W), g\nStage\nNumber of individuals (samples 1+2)\nLength (L), mm\nWeight (W), g\n1\n4 + 24\n2.02\n0.107\n6\n22 + 20\n4.22\n1\n2\n37 + 74\n2.74\n0.265\n7\n19 + 8\n4.76\n1.261\n3\n23 + 22\n3.24\n0.408\n8\n11 + 17\n5.3\n1.698\n4\n5 + 12\n3.84\n0.657\n9\n1 + 11\n5.52\n1.788\n5\n7 + 29\n3.88\n0.659\n10\n1 + 15\n6.42\n2.597\n\nAs seen from Table 1, the samples differ in the relative numbers of tadpoles at different developmental stages. Comparing the observed distribution with the theoretical one built under the assumption of independence between sample and stage, Pearson χ² = 34.4, which for the given degrees of freedom corresponds to highly significant differences (p = 0.000075). The predominance of late‑stage tadpoles in sample 2 is probably due to a longer development period.\nSummary. Described stage of the development of the hind limbs of water frog (Pelophylax esculentus complex). The studied polliwogs were caught in the river Seversky Donec near Zmiev. Dependency of the weight (W) of polliwog on its body length (L) is of the form W = 0.26 – 0.27 L + 0.098 L².\nThe described results were obtained during a teaching‑research work in the vertebrate zoology practicum. The authors express gratitude to associate professor D. A. Shabanov for supervision of this work.\nVinogradska T. I., Tolokneeva A. A., Komarova E. V., Khloponina V. V., Bibik Yu. S. Growth and development of green frog tadpoles in natural habitat // \"Biology: from molecule to biosphere\". Materials of the V International Conference of Young Scientists. - Kharkiv: Operatyvna Polihrafia, 2010. p. 344‑345.\nSTUDY OF FLUCTUATING ASYMMETRY OF COLOURING IN GREEN FROGS\nKryshchal O. A., Matasova E. V.\nKharkiv National University named after V.N. Karazin, Faculty of Biology, Svobody Square, 4, Kharkiv, Ukraine\nDetermination of the level of fluctuating asymmetry (FA – random deviations from bilateral symmetry) is one way to assess ontogenetic stability. Development in interspecific hybrids is usually less stable than in parental species. In the vicinity of the HNU biostation in the village of Haidary (Zmiievsky district, Kharkiv region) among European green frogs live representatives of the parental species Pelophylax ridibundus (lake frogs) and hemiclonal interspecific hybrids Pelophylax esculentus (edible frogs). In 2008 the FA of their coloration was studied using conventional traits – asymmetry of the dorsomedial stripe, number of spots on the back and spot‑stripes on the hind limbs (Deryazhenkova et al., 2008). Strangely, the FA of hybrids in this study did not exceed that of the parental species. We applied a new method for measuring FA in frogs, assuming it would be more sensitive to deviations from colour symmetry.\nIn the floodplain of the Seversky Donets near Haidary, 186 green frogs were captured. They were identified by external traits: low and sloping heel tubercle, absence of yellowish hue on thighs, dark vocal sacs in males correspond to P. ridibundus; high tubercle, presence of yellow hue on thighs, light vocal sacs in males correspond to P. esculentus. We identified 107 individuals (46 females, 36 males and 25 subadults) as P. esculentus, 55 individuals (31+12+12 respectively) as P. ridibundus, and 24 individuals (12+6+6) remained unidentified due to atypical trait combinations.\nThe dorsal side of the body and limbs of each frog was photographed (the frog was made to grasp a support with its forelimbs and stretched lengthwise by the hind‑limb toes), then released at the capture site. In CorelDraw a grid was overlaid on each photograph, dividing it along the frog’s body axis from snout to heel tubercles into 20 zones. For all zones where possible, colour symmetry was classified as symmetrical (S), slightly asymmetrical (H) or strongly asymmetrical (A). The numbers of zones of each type (NS, NH, NA) were counted. Results were processed in Statistica. Asymmetry of an individual was calculated as FA = (NA + NH/2) / NS.\nFA traits, taking the sign of deviation into account, have a normal distribution with mean 0. Our FA measure takes only positive values. The most frequent values were near 0; as FA increased, frequency decreased. This distribution confirms that the used measure characterises FA and can be applied to study developmental stability in frogs and probably other animals. P. esculentus proved significantly (Mann‑Whitney p=0.031) more asymmetrical than P. ridibundus. The median FA for P. esculentus is 0.4, for P. ridibundus – 0.33, and for unidentified individuals – 0.39. The influence of sex and age on colour FA was not significant.\nSummary. For study fluctuating asymmetry (FA) tinge in water frogs, their photographed from back side. Photography was dividing along axis body on 20 zones. We counted the symmetrical, weak and hard asymmetrical zones. The tinge of hybrids form water frogs P. esculentus was found a more asymmetrical, then tinge of representatives by generation species water frogs P. ridibundus.\nThe work was performed as a UIRS during the vertebrate zoology practicum. The authors thank associate professor D. A. Shabanov for the idea of the work and scientific supervision.\nKryshchal O. A., Matasova E. B. Study of fluctuating asymmetry of coloration in green frogs. // \"Biology: from molecule to biosphere\". Materials of the V International Conference of Young Scientists. - Kharkiv: Operatyvna Polihrafia. 2010. - p. 355-356." }

Samples 3-5, which developed under identical conditions but likely differed in genotype, showed significant differences in the ratio of the seven registered oral apparatus types (comparison by chi-squared criterion p<0.00001). It appears that genotypic peculiarities of the frogs are reflected in the diversity of oral apparatuses. In samples 1 and 2, obtained from the natural environment, types A, B, C, and E were not detected, but types H and I were found. Finally, in samples 6 and 7, consisting solely of P. ridibundus tadpoles, only 2 types of oral apparatuses were registered: G and I. The least diversity of oral apparatus types is characteristic of single-species samples from the natural environment, while the greatest diversity is found in mixed samples that developed under artificial conditions. Therefore, the diversity of tadpole oral apparatuses is influenced by their species, genotype, and developmental conditions, but none of these factors can fully explain the observed variability of their oral apparatuses.