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Behavioural Characters (behavioural + character)
Selected AbstractsPhylogenetic analysis of the pearlfish tribe Carapini (Pisces: Carapidae)ACTA ZOOLOGICA, Issue 4 2000E. Parmentier Abstract Fishes of the tribe Carapini (Encheliophis and Carapus) share a noteworthy peculiarity: they shelter in holothurian echinoderms or bivalve hosts. Some species are considered parasitic, others commensal. This study focuses on the phylogeny of the tribe, using two other Carapidae species as an outgroup (Snyderidia canina and Onuxodon fowleri). Insofar as possible, the selected anatomical and behavioural characters where chosen in an ecomorphological perspective, as features that could be responses to various lifestyle-related constraints. Our character selection also took into account the fact that some features are (presumably) linked. Such features were grouped together as a single trait to avoid their overvaluation. This methodology enabled commensals to be separated from parasites, the former belonging to Carapus and the latter to Encheliophis. Carapus species reflect in their morphology the constraints imposed by a diet of hard, mobile, elusive prey, showing predator-type features: a strong dentition, a wide mouth opening, a robust food intake apparatus. On the other hand, the endoparasitic Encheliophis species show a generally weaker buccal apparatus and narrow mouth opening, in relation to the different constraints of their lifestyle where the diet constraints are less pronounced: they eat body parts of their host. Changes in both generic diagnoses are proposed and three species are transferred from Encheliophis to Carapus. [source] From kissing to belly stridulation: comparative analysis reveals surprising diversity, rapid evolution, and much homoplasy in the mating behaviour of 27 species of sepsid flies (Diptera: Sepsidae)JOURNAL OF EVOLUTIONARY BIOLOGY, Issue 11 2009N. PUNIAMOORTHY Abstract Our understanding of how fast mating behaviour evolves in insects is rather poor due to a lack of comparative studies among insect groups for which phylogenetic relationships are known. Here, we present a detailed study of the mating behaviour of 27 species of Sepsidae (Diptera) for which a well-resolved and supported phylogeny is available. We demonstrate that mating behaviour is extremely diverse in sepsids with each species having its own mating profile. We define 32 behavioural characters and document them with video clips. Based on sister species comparisons, we provide several examples where mating behaviour evolves faster than all sexually dimorphic morphological traits. Mapping the behaviours onto the molecular tree reveals much homoplasy, comparable to that observed for third positions of mitochondrial protein-encoding genes. A partitioned Bremer support (PBS) analysis reveals conflict between the molecular and behavioural data, but behavioural characters have higher PBS values per parsimony-informative character than DNA sequence characters. [source] Patterns of population subdivision and gene flow in the ant Nothomyrmecia macrops reflected in microsatellite and mitochondrial DNA markersMOLECULAR ECOLOGY, Issue 9 2003M. Sanetra Abstract The Australian endemic ant Nothomyrmecia macrops is renowned for having retained a large proportion of ,primitive' morphological and behavioural characters. Another less studied peculiarity of this species is the production of short-winged (brachypterous) female sexuals, which presumably are poor dispersers. The males, in contrast, bear a full set of normally developed wings and thus may disperse widely. We investigated patterns of genetic differentiation within and among three distantly separated populations in South Australia using nine polymorphic microsatellite loci and four regions of mitochondrial DNA (COI, COII, Cytb, lrRNA). We sampled eight subpopulations, one in the Lake Gilles CP, two near Penong and five around Poochera where distances ranged from 360 km to sites separated by 2,10 km. Only little differentiation was found at the local scale (within the assumed dispersal distance of males) using nuclear markers, whereas the three distant locations were moderately differentiated (FST = 0.06). Mitochondrial DNA genetic structure was much more pronounced on all scales (,ST = 0.98), with regular differences in both haplotype composition and frequency even occurring among closely located sites. This lack of congruence between nuclear and mitochondrial markers strongly suggests limited female dispersal and male-biased gene flow among populations. As to the conservation status of the species there is no evidence for severe population reductions in the recent past, which would have left populations genetically depauperate. [source] Genetic variation in the life-history traits of Epiphyas postvittana: population structure and local adaptationAUSTRAL ECOLOGY, Issue 4 2000Hainan Gu Abstract The light brown apple moth, Epiphyas postvittana (Walker) shows high intraspecific variability in morphological, physiological, demographic and behavioural characters. To gain insight into the extent of adaptation and evolutionary changes in response to environmental heterogeneity in this species, quantitative genetic analyses of life-history variation were conducted for two natural populations under two thermal conditions (23°C and 28°C). Paternal half-sib heritability and genetic correlation in six life-history traits (i.e. development time, adult body weight, adult lifespan, age at first reproduction, the number of eggs laid during the first 5 days after emergence, and total fecundity) were compared. Significant heritabilities were shown consistently in development time; this is also true for adult body weight, except for the Canberra population at 23°C. However, neither population differences nor the effect of temperature were statistically detectable for any of these heritabilities, confirming the genetically determined flexibility. Positive genetic correlations between development time and adult body weight, and negative genetic correlations between the number of eggs laid during the first 5 days and adult lifespan were present for these populations at both temperatures, indicating the presence of genetic constraints. Pairwise comparisons of genetic correlations revealed the heterogeneity of the two populations and across temperatures. These results suggest that the structure of genetic covariance might have changed significantly during the divergence of natural populations and in response to the alteration of environmental conditions in E. postvittana. [source] Genetic variation in the life-history traits of Epiphyas postvittana: population structure and local adaptationAUSTRAL ECOLOGY, Issue 4 2000HAINAN GU Abstract The light brown apple moth, Epiphyas postvittana (Walker) shows high intraspecific variability in morphological, physiological, demographic and behavioural characters. To gain insight into the extent of adaptation and evolutionary changes in response to environmental heterogeneity in this species, quantitative genetic analyses of life-history variation were conducted for two natural populations under two thermal conditions (23°C and 28°C). Paternal half-sib heritability and genetic correlation in six life-history traits (i.e. development time, adult body weight, adult lifespan, age at first reproduction, the number of eggs laid during the first 5 days after emergence, and total fecundity) were compared. Significant heritabilities were shown consistently in development time; this is also true for adult body weight, except for the Canberra population at 23°C. However, neither population differences nor the effect of temperature were statistically detectable for any of these heritabilities, confirming the genetically determined flexibility. Positive genetic correlations between development time and adult body weight, and negative genetic correlations between the number of eggs laid during the first 5 days and adult lifespan were present for these populations at both temperatures, indicating the presence of genetic constraints. Pairwise comparisons of genetic correlations revealed the heterogeneity of the two populations and across temperatures. These results suggest that the structure of genetic covariance might have changed significantly during the divergence of natural populations and in response to the alteration of environmental conditions in E. postvittana. [source] | ||||||||||