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Although sexual dimorphism in morphological traits (SD) has been widely studied in many animal groups (including arthropods), its developmental mechanisms are poorly understood. As ontogenetic allometry describes whether size of a morphological trait significantly affects changes of its shape during ontogeny, comparison of allometric growth trends between sexes can reveal whether and how intersexual differences in developmental pathways influence the presence and patterns of SD in adults. We studied allometric relationships between 10 morphological traits (head length and width, gnathochilarium length and width, antennal length, trunk length, width and height, leg length, body mass) and body length in different ontogenetic stadia of both sexes of the Balkan endemic millipede Apfelbeckia insculpta (L. Koch, 1867) using bivariate and multivariate analyses. Our sample consisted of 61 males and 60 females belonging to two sub-adult groups (postembryonic stadia VIII and IX) and adults (postembryonic stadium X). All individuals were collected from Hadži Prodanova Pećina Cave (Serbia). We detected that all morphological traits share common slope between sub-adults and adults of the same sex. Significant SD in common slope was detected for head and gnathochilarium dimensions and body mass. Also, these traits, together with antennal and leg length, showed different allometric growth trends between sexes. Our data show that SD in morphological traits in adults is achieved through intersexual differences in growth rates, as well as through differences in allometric growth trends. This study suggests allometric scaling as key process in development of adult body plan in A. insculpta.

Morphological integration is defined as covariation of multiple parts of the morphological traits. Modularity is characterized by the presence of subunites (modules), which have high level of integration within themselves, but weak between themselves. In this respect, differences in function, anatomical structure and embrionical origin of modules can influence development and function of organism. The aim of our study was to test the hypothesis that the distal region of the head capsule is a modul in Megaphyllum unilineatum using geometric morphometrics. Millipedes belonging to postembryonic stadia VI to XI were collected from Krnjača, Belgrade. The ontogenetic stadia were determined by counting the number of rows of ocelli, the total number of ocelli and rings, and the number of rings with and without walking legs. In data processing, the following statistical programs were used: MakeFan, TpsDig, CoordGen, MorphoJ, and R program. Procrustes ANOVA showed that individual × side interaction was significant. Allometry was significant for the symmetric component (SC), but not for the asymmetric component (FA). Since covariance coefficients (RV) for SC and FA had lower values than 10.4% and 13.8% (respectively) of other RV coefficients obtained by a random contiguous partition of dorsal part of the head capsule, modularity hypothesis is rejected. Further, the scaled variance of the eigenvalues of the SC (EV) was significantly lower before than after allometry removal. These results indicate that distal and proximal regions of the head capsule, due to their strongly morphological integration, develop and function as a module during ontogeny in this species.

Pesticides can have a lethal or sublethal effect on spiders and are able to influence their locomotion, activity, web building, reproduction and abundance. Effects of pesticides on spider morphological variations have been poorly investigated. In this study, we explored the influence of pyrethroid insecticides (Fastac®, Talstar® and Trebon®) on variations of linear measurements (body length, carapace and abdomen length, carapace and abdomen width) and carapace shape in Oedothorax apicatus (Blackwall, 1850) from conventional, integrated and organic oilseed rape fields. Multiple applications of various pyrethroid insecticides on the conventional field over a longer period of time influenced significantly the morphological variability in female specimens only. These females had longer bodies with longer and wider carapaces and abdomens in comparison with females from the organic and integrated fields. A wider posterior part of the carapace and less protruded frontal part were detected in female spiders from the integrated and conventional fields. We presumed that these results may be attributed to faster growth, which might be the consequence of a pyrethroid hormetic effect on female individuals. In the case of male spiders, significant morphological differences between the experimental fields were not observed, probably due to their higher mobility.

Agrochemicals can have significant influence on the biodiversity of predators in terrestrial agroecosystems. Pesticides in general can have lethal or sublethal effects on spiders and influence their activity, locomotion, web building – and reproduction behaviours as well as abundance. The effect of pesticides on spider morphologial variations has been poorly investigated. In this study, we explored the influence of pyrethroid insecticides (Fastac®, Talstar®, Trebon®) on morphological variations in body length, carapace and abdomen length, carapace and abdomen width, and carapace shape in Oedothorax apicatus (Blackwall, 1850) collected from conventional, integrated and organically-produced oilseed rape crops. Multiple applications of various pyrethroid insecticides on the conventional field significantly influenced morphological variability in female specimens. These females had longer bodies with longer and wider carapace and abdomen in comparison to females from fields under organic and integrated management. Wider posterior part of the carapace and less protruded frontal part was detected in female spiders from fields under integrated and conventional management. These results can be explained by faster growth as a consequence of pyrethroid hormetic effects on female individuals. In male spiders significant morphological differences between individuals collected from the different experimental fields were not observed, probably due to their higher mobility.

Uticaj heterogenih uslova svetlosti i antropogeno indukovanog stresa (gaženja i aerozagađenja) na oblik i veličinu lista Mercurialis perennis i delova cveta Iris pumila, procenjen je primenom geometrijske morfometrije. Takođe je proučavan i uticaj navedenih faktora na varijabilnost osobina izdanaka M. perennis (visine biljke, broja listova i broja internodija). S obzirom na to da je M. perennis dvodoma biljka, analizirano je i prisustvo polnog dimorfizma i potencijalnih polno–specifičnih reakcija na suboptimalne uslove staništa. Uticaj heterogenih uslova svetlosti i aerozagađenja na stepen integracije oblika različitih delova cveta I. pumila procenjivan je na osnovu obrazaca korelacionih odnosa. Biljne vrste M. perennis i I. pumila su se u dosadašnjim istraživanjima pokazale kao pogodni model–sistemi za istraživanja u oblasti evolucione biologije biljaka. Šumski prosinac, Mercurialis perennis L. (Euphorbiaceae), je dvodoma višegodišnja zeljasta biljka, karakteristična pre svega za stara šumska staništa, primarna ili manje narušena, ali se može naći i na otvorenim, kao i na staništima pod jakim antropogenim uticajem. Kao dvodoma vrsta, predstavlja atraktivan objekat za proučavanje različitih aspekata polnog dimorfizma kod biljaka. Patuljasta perunika, Iris pumila L. (Iridaceae), je višegodišnja monokotila iz grupe geofita, karakteristična je pre svega za otvorena, uglavnom suva nizijska do brdska staništa. U ovo istraživanje uključene su populacije M. perennis sa lokaliteta Avala i Bele stene (Kopaonik), kao i populacije I. pumila sa lokaliteta Deliblatska peščara i Beograd. Pored toga, analizirani su i cvetovi I. pumila gajeni u eksperimentalnim uslovima jasno definisanog intenziteta i kvaliteta svetlosti. Analizirano je 90 biljaka M. perennis i 120 biljaka (ukupno 60 genotipova) I. pumila sa prirodnih staništa izloženih heterogenim uslovima svetlosti, 170 biljaka (33 genotipa) I. pumila gajenih u eksperimentalnim uslovima pod različitim svetlosnim tretmanima, kao i 119 biljaka M. perennis i 120 biljaka (41 genotip) I. pumila sa staništa izloženih različitom nivou antropogeno indukovanog stresa... Impact of heterogeneous light conditions and anthropogenically induced stress (trampling and air polluton) on shape and size of leaves in Mercurialis perennis and flower parts in Iris pumila, was assessed by means of geometric morphometrics. The effect of mentioned factors on variability of shoot traits in M. perennis (plant height, number of leaves and internodes) was also explored. Since M. perennis is a dioecious plant, presence of sexual dimorphism and potential sex–specific reaction to suboptimal habitat conditions was investigated. The effect of heterogeneous light conditions and air pollution on degree of integration of shape of different floral parts of I. pumila was determined based on changes in patterns of covariation among mentioned structures. Mercurialis perennis and Iris pumila have proved themselves to be suited model systems in plant evolutionary biology research. Dog`s mercury, Mercurialis perennis L. (Euphorbiaceae), is a dioecious perennial forb, typical of ancient undisturbed woodlands, but it can also occur in open conditions and under strong antropogenic disturbance. As a dioecious herb, it represents an attractive object for research of different aspects of sexual dimorphism in plants. Dwarf iris, Iris pumila L. (Iridaceae), is monocot, perennial, geophyte typically inhabiting open, dry lowlands. This research included M. perennis populations from Avala and Bele stene (Kopaonik) as well as I. pumila populations from Deliblato Sands and Belgrade. Additionally, flowers of I. pumila grown under experimentally explicitly manipulated light intensity and quality conditions were analyzed. The study included a total of 90 M. perennis and 120 I. pumila plants (sum 60 genotypes) from natural habitat exposed to heterogeneous light conditions, 170 I. pumila plants (33 genotypes) grown under different light experimental treatments, as well as 119 M. perennis and 120 I. pumila plants (41 genotypes) from sites exposed to different levels of anthropogenically induced stress...

The goal of this study was to analyze variation and covariation in epidermal characteristics (epidermal cell density -ECD, stomata density - SD, and stomata index - SI) on Iris pumila clones on between-clone, between-leaf and within-leaf levels. ECD (similar to the pattern previously observed for SD) increased from the base to the top of leaf, while SI remained constant. Results of profile analyses indicated that clones, individual plants whitin clones (ramets), and three successive leaves on the same plant were not significantly different for examined characteristics, but genetic variation for position effect was detected (significant Zone x clone interaction). Results of the contrast analysis confirmed differences between the base and middle leaf positions for ECD (similar to those for SD) as well as between clone variation for those differences. Observed differences between leaf zones and correlations between analyzed traits were mostly consistent with the expansion hypothesis of stomata differentiation. Cilj ovog istraživanja je analiza variranja i kovariranja epidermalnih osobina lista (gustina epidermalnih ćelija ECD, gustina stoma SD i stomatalni indeks SI) između i unutar lista kao i između klonova Iris pumila. Gustina epidermalnih ćelija (slično obrascu gustina stoma, ranije publikovano) raste od baze ka vrhu lista, dok vrednost stomatalnog indeksa ostaje konstantna. Rezultati Profile analize (MANOVA) ukazuju da se klonovi, individualne biljke svakog klona (rameta), kao i tri sukcesivna lista na svakoj od biljaka ne razlikuju za ispitivane karakteristike epidermisa lista (epidermalna gustina lista i stomatalni indeks). Međutim, variranje unutar lista na različitim pozicijama lista (baza, sredina i vrh lista), uslovljeno razlikama genotipa (klonovima) je potvrđeno statistički značajnom interakcijom zona (pozicija na listu) x klon (P < 0.05). Razlike između baze i sredine lista za gustinu epidermalnih ćelija (F = 199.46, P < 0.0001), kao i značajna razlika između klonova između pomenutih pozicija je prema rezultatima analize kontrasta statistički značajna (F = 6.29, P < 0.001). Dobijene razlike između pozicija na listu i korelacija između analiziranih epidermalnih osobina lista I.pumila klonova su potvrda hipoteze širenja epidermalnih ćelija prilikom diferencijacije stoma unutar lista. Projekat ministarstva br. OI 173025