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Sökning: WFRF:(Kodandaramaiah Ullasa)

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1.
  • Aduse-Poku, Kwaku, et al. (författare)
  • Molecular phylogeny and generic-level taxonomy of the widespread palaeotropical 'Heteropsis clade' (Nymphalidae : Satyrinae: Mycalesina)
  • 2016
  • Ingår i: Systematic Entomology. - : Wiley. - 0307-6970. ; 41:4, s. 717-731
  • Tidskriftsartikel (refereegranskat)abstract
    • The mycalesine butterfly genus Heteropsis Westwood, 1850 (Satyrinae: Mycalesina) has recently been conceived to be represented in three major palaeotropical regions (Madagascar, Africa and Asia), but there has been no formal taxonomic treatment covering this entire group. Studies aimed at understanding the evolutionary success of Mycalesina in the Old World tropics have been hampered by the lack of both a robust phylogeny and a stable nomenclature for this satyrine subtribe. Here, we present a well-supported molecular phylogeny based on 10 genes and 133 exemplar taxa, representing almost all known species groups of Heteropsis (s.l.), and including all but four known species in Madagascar. We also combine sequences of the exemplars with a morphological matrix of 428 characters. The widespread 'Heteropsis clade' is confirmed as monophyletic, but lineages in different geographic regions also form endemic and well-supported clades with deep divergences among them. Here we establish this group as comprising three genera, Heteropsis (Malagasy region only), Telinga Moore, 1880 (Asia), and Brakefieldia gen.n. (Africa). We recover the genera Telinga and Brakefieldia as sisters with high support. Each genus is taxonomically characterized and a revised synonymic checklist is appended with new combinations and some changes in rank. With a well-resolved topology and updates to the taxonomy of the group, researchers are now in a position to explore the drivers of the spectacular radiation of the group, notably in Madagascar, where the highest phenotypic and species diversity occurs.
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2.
  • Aduse-Poku, Kwaku, et al. (författare)
  • Systematics and historical biogeography of the Old World butterfly subtribe Mycalesina (Lepidoptera: Nymphalidae: Satyrinae)
  • 2015
  • Ingår i: BMC Evolutionary Biology. - : Springer Science and Business Media LLC. - 1471-2148. ; 15, s. 167-167
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: Butterflies of the subtribe Mycalesina have radiated successfully in almost all habitat types in Africa, Madagascar, the Indian subcontinent, Indo-China and Australasia. Studies aimed at understanding the reasons behind the evolutionary success of this spectacular Old World butterfly radiation have been hampered by the lack of a stable phylogeny for the group. Here, we have reconstructed a robust phylogenetic framework for the subtribe using 10 genes from 195 exemplar taxa. RESULTS: We recovered seven well supported clades within the subtribe corresponding to the five traditional genera (Lohora, Heteropsis, Hallelesis, Bicyclus, Mycalesis), one as recently revised (Mydosama) and one newly revised genus (Culapa). The phylogenetic relationships of these mycalesine genera have been robustly established for the first time. Within the proposed phylogenetic framework, we estimated the crown age of the subtribe to be 40 Million years ago (Mya) and inferred its ultimate origin to be in Asia. Our results reveal both vicariance and dispersal as factors responsible for the current widespread distribution of the group in the Old World tropics. We inferred that the African continent has been colonized at least twice by Asian mycalesines within the last 26 and 23 Mya. In one possible scenario, an Asian ancestor gave rise to Heteropsis on continental Africa, which later dispersed into Madagascar and most likely back colonised Asia. The second colonization of Africa by Asian ancestors resulted in Hallelesis and Bicyclus on continental Africa, the descendants of which did not colonise other regions but rather diversified only in continental Africa. The genera Lohora and Mydosama are derivatives of ancestors from continental Asia. CONCLUSION: Our proposed time-calibrated phylogeny now provides a solid framework within which we can implement mechanistic studies aimed at unravelling the ecological and evolutionary processes that culminated in the spectacular radiation of mycalesines in the Old World tropics.
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3.
  • Chazot, Nicolas, et al. (författare)
  • Conserved ancestral tropical niche but different continental histories explain the latitudinal diversity gradient in brush-footed butterflies
  • 2021
  • Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 12:1
  • Tidskriftsartikel (refereegranskat)abstract
    • The global increase in species richness toward the tropics across continents and taxonomic groups, referred to as the latitudinal diversity gradient, stimulated the formulation of many hypotheses to explain the underlying mechanisms of this pattern. We evaluate several of these hypotheses to explain spatial diversity patterns in a butterfly family, the Nymphalidae, by assessing the contributions of speciation, extinction, and dispersal, and also the extent to which these processes differ among regions at the same latitude. We generate a time-calibrated phylogeny containing 2,866 nymphalid species (~45% of extant diversity). Neither speciation nor extinction rate variations consistently explain the latitudinal diversity gradient among regions because temporal diversification dynamics differ greatly across longitude. The Neotropical diversity results from low extinction rates, not high speciation rates, and biotic interchanges with other regions are rare. Southeast Asia is also characterized by a low speciation rate but, unlike the Neotropics, is the main source of dispersal events through time. Our results suggest that global climate change throughout the Cenozoic, combined with tropical niche conservatism, played a major role in generating the modern latitudinal diversity gradient of nymphalid butterflies.
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4.
  • Friberg, Magne, et al. (författare)
  • Genetic differentiation and phylogeographic patterns in European populations of Leptidea sinapis and L. reali
  • Annan publikation (refereegranskat)abstract
    • The direction of a coevolutionary interaction can differ between local populations as in the butterflies Leptidea sinapis and L. reali. The morphologically virtually identical sister-species have partitioned their niches differently in different parts of their distribution by shifting habitat specialist and generalist roles between different sympatric areas. Hence, a species that is a generalist in some areas can be a local specialist in others, and vice versa. We have sequenced the mitochondrial COI gene from specimens collected across Europe in order to (i) describe the between-species variation over a large area, (ii) identify possible glacial refugia and re-colonisation routes to obtain a phylogeographic hypothesis for explaining the geographic mosaic of niche separation and (iii) apply a population genetic approach to determine the level of intraspecific genetic differentiation. The results show evidence for species distinctiveness throughout Europe. Only small variation was found in L. reali, whereas the haplotype network of L. sinapis showed a deep division into two haplotype families of which one was restricted to Spain and the other was widespread over the continent (including Spain). The widespread haplotype family was divided into two common variants, one eastern and one western, each being surrounded by rare haplotypes. The both deep and shallow genetic differentiation implies that L. sinapis might have been divided into different refugia during several glaciations. Both species showed significant genetic differentiation in pairwise ФST, and as habitat generalist populations could differ significantly from other habitat generalist populations but not from habitat specialist populations, we conclude that this study supports that the geographic mosaic of niche separation is caused by local processes rather than common ancestry of local habitat generalists or specialists within each species
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5.
  • Kodandaramaiah, Ullasa, et al. (författare)
  • Deceptive single-locus taxonomy and phylogeography : Wolbachia-associated divergence in mitochondrial DNA is not reflected in morphology and nuclear markers in a butterfly species
  • 2013
  • Ingår i: Ecology and Evolution. - : Wiley. - 2045-7758. ; 3:16, s. 5167-5176
  • Tidskriftsartikel (refereegranskat)abstract
    • The satyrine butterfly Coenonympha tullia (Nymphalidae: Satyrinae) displays a deep split between two mitochondrial clades, one restricted to northern Alberta, Canada, and the other found throughout Alberta and across North America. We confirm this deep divide and test hypotheses explaining its phylogeographic structure. Neither genitalia morphology nor nuclear gene sequence supports cryptic species as an explanation, instead indicating differences between nuclear and mitochondrial genome histories. Sex-biased dispersal is unlikely to cause such mito-nuclear differences; however, selective sweeps by reproductive parasites could have led to this conflict. About half of the tested samples were infected by Wolbachia bacteria. Using multilocus strain typing for three Wolbachia genes, we show that the divergent mitochondrial clades are associated with two different Wolbachia strains, supporting the hypothesis that the mito-nuclear differences resulted from selection on the mitochondrial genome due to selective sweeps by Wolbachia strains.
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6.
  • Kodandaramaiah, Ullasa, et al. (författare)
  • Deflective and intimidating eyespots : a comparative study of eyespot size and position in Junonia butterflies
  • 2013
  • Ingår i: Ecology and Evolution. - : Wiley. - 2045-7758. ; 3:13, s. 4518-4524
  • Tidskriftsartikel (refereegranskat)abstract
    • Eyespots are conspicuous circular features found on the wings of several lepidopteran insects. Two prominent hypotheses have been put forth explaining their function in an antipredatory role. The deflection hypothesis posits that eyespots enhance survival in direct physical encounters with predators by deflecting attacks away from vital parts of the body, whereas the intimidation hypothesis posits that eyespots are advantageous by scaring away a potential predator before an attack. In the light of these two hypotheses, we investigated the evolution of eyespot size and its interaction with position and number within a phylogenetic context in a group of butterflies belonging to the genus Junonia. We found that larger eyespots tend to be found individually, rather than in serial dispositions. Larger size and conspicuousness make intimidating eyespots more effective, and thus, we suggest that our results support an intimidation function in some species of Junonia with solitary eyespots. Our results also show that smaller eyespots in Junonia are located closer to the wing margin, thus supporting predictions of the deflection hypothesis. The interplay between size, position, and arrangement of eyespots in relation to antipredation and possibly sexual selection, promises to be an interesting field of research in the future. Similarly, further comparative work on the evolution of absolute eyespot size in natural populations of other butterfly groups is needed.
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7.
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8.
  • Kodandaramaiah, Ullasa (författare)
  • Eyespot evolution : phylogenetic insights from Junonia and related butterfly genera (Nymphalidae)
  • 2009
  • Ingår i: Evolution & Development. - 1520-541X .- 1525-142X. ; 11:5, s. 489-497
  • Tidskriftsartikel (refereegranskat)abstract
    • Butterfly eyespots have been the focus of a number of developmental and evolutionary studies. However, a phylogenetic component has rarely been explicitly incorporated in these studies. In this study, I utilize a phylogeny to trace the evolution of eyespot number and position on the wing in a group of nymphalid butterflies, the subtribe Junoniini. These butterflies have two kinds of eyespot arrangements which I refer to as Serial and Individual. In the Serial arrangement, eyespots are placed in a series on compartments 1-6 (counting from the anterior wing margin). In the Individual arrangement, eyespots are isolated on specific compartments, ranging from 1 to 4 in number. This can be divided into four subtypes based on the number and positions of eyespots. I map the evolution of these five arrangements over a phylogeny of Junoniini reconstructed with ca. 3000 base pairs of sequence data from three genes. The results show that almost all arrangements have evolved at least twice, with multiple shifts between them by addition and deletion of eyespots. I propose a model involving genetic or developmental coupling between eyespots in specific compartments to explain these shifts. I discuss their evolution in light of existing knowledge about their development. I also discuss potential explanations for functional significance of the eyespot patterns found in the group. Differential selection for and against eyespots, both at different times over the phylogeny and in different regions, have driven the evolution of eyespot arrangements. The study throws open many questions about the adaptive significance of eyespots and the developmental underpinnings of the various arrangements.
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9.
  • Kodandaramaiah, Ullasa, et al. (författare)
  • Fixed eyespot display in a butterfly thwarts attacking birds
  • 2009
  • Ingår i: Animal Behaviour. - London, England : ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD. - 0003-3472 .- 1095-8282. ; 77:6, s. 1415-1419
  • Tidskriftsartikel (refereegranskat)abstract
    • Eyespots have evolved in many lepidopteran insects, which suggests their adaptive value. One of their hypothesized functions is that predators are intimidated by prey with large and conspicuous eyespots and hence refrain from attacking them. Recent experiments have shown that a combination of eyespots and intimidating behaviour can increase survival. We tested whether the mere presence of conspicuous eyespots can thwart attacking birds, that is, when the eyespots are displayed constantly, without any intimidating behaviour. We used prey that consisted of wings of the peacock pansy butterfly, Junonia almana, glued onto a piece of cardboard so as to resemble a butterfly with its wings open. A mealworm was placed between the wings in place of the body. Great tits, Parus major, were used as the predator in the study and were offered a choice between two model prey, one with intact eyespots and one without. Prey with eyespots were attacked significantly fewer times than those without. The time between the first and second attack was longer when the prey without eyespots was attacked first. These results support the hypothesis that naturally occuring butterfly eyespots can increase survival even when they are constantly displayed and motionless.
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10.
  • Kodandaramaiah, Ullasa, et al. (författare)
  • Investigating concordance among genetic data, subspecies circumscriptions and hostplant use in the nymphalid butterfly polygonia faunus
  • 2012
  • Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 7:7, s. e41058-
  • Tidskriftsartikel (refereegranskat)abstract
    • Subspecies are commonly used taxonomic units to formally describe intraspecific geographic variation in morphological traits. However, the concept of subspecies is not clearly defined, and there is little agreement about what they represent in terms of evolutionary units, and whether they can be used as reliably useful units in conservation, evolutionary theory and taxonomy. We here investigate whether the morphologically well-characterized subspecies in the North American butterfly Polygonia faunus are supported by genetic data from mitochondrial sequences and eight microsatellite loci. We also investigate the phylogeographic structure of P. faunus and test whether similarities in host-plant use among populations are related to genetic similarity. Neither the nuclear nor the mitochondrial data corroborated subspecies groupings. We found three well defined genetic clusters corresponding to California, Arizona and (New Mexico+Colorado). There was little structuring among the remaining populations, probably due to gene flow across populations. We found no support for the hypothesis that similarities in host use are related to genetic proximity. The results indicate that the species underwent a recent rapid expansion, probably from two glacial refugia in western North America. The mitochondrial haplotype network indicates at least two independent expansion phases into eastern North America. Our results clearly demonstrate that subspecies in P. faunus do not conform to the structuring of genetic variation. More studies on insects and other invertebrates are needed to better understand the scope of this phenomenon. The results of this study will be crucial in designing further experiments to understand the evolution of hostplant utilization in this species.
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11.
  • Kodandaramaiah, Ullasa, et al. (författare)
  • Out-of-Africa origin and dispersal mediated diversification of the butterfly genus Junonia (Nymphalidae: Nymphalinae)
  • 2007
  • Ingår i: Journal of Evolutionary Biology. - : Wiley. - 1010-061X .- 1420-9101. ; 20:6, s. 2181-2191
  • Tidskriftsartikel (refereegranskat)abstract
    • The relative importance of dispersal and vicariance in the diversification of taxa has been much debated. Within butterflies, a few studies published so far have demonstrated vicariant patterns at the global level. We studied the historical biogeography of the genus Junonia (Nymphalidae: Nymphalinae) at the intercontinental level based on a molecular phylogeny. The genus is distributed over all major biogeographical regions of the world except the Palaearctic. We found dispersal to be the dominant process in the diversification of the genus. The genus originated and started diversifying in Africa about 20 Ma and soon after dispersed into Asia possibly through the Arabian Peninsula. From Asia, there were dispersals into Africa and Australasia, all around 5 Ma. The origin of the New World species is ambiguous; the ancestral may have dispersed from Asia via the Beringian Strait or from Africa over the Atlantic, about 3 Ma. We found no evidence for vicariance at the intercontinental scale. We argue that dispersal is as important as vicariance, if not more, in the global diversification of butterflies.
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12.
  • Kodandaramaiah, Ullasa, et al. (författare)
  • Phylogenetic relationships, biogeography and diversification of Coenonymphina butterflies (Nymphalidae : Satyrinae): intercontinental dispersal of a southern Gondwanan group?
  • 2018
  • Ingår i: Systematic Entomology. - : Wiley. - 0307-6970 .- 1365-3113. ; 43:4, s. 798-809
  • Tidskriftsartikel (refereegranskat)abstract
    • The origins, evolutionary history and diversification of the Australian butterfly fauna are poorly known and uncertain. Two competing hypotheses have been proposed to explain the occurrence of butterflies on this isolated continental landmass. The common view is that all Australian butterflies entered the continent relatively recently from the northern hemisphere via Southeast Asia and/or mainland New Guinea (i.e. northern dispersal origin hypothesis). The alternative view is that part or all of the Australian butterfly fauna ultimately evolved in remnant or Southern Gondwana when Australia was connected to South America through Antarctica (i.e. Southern Gondwanan origin hypothesis). However, robust phylogenies with strong support for monophyly are lacking for the majority of Australian endemic butterfly lineages, thereby precluding determination of their systematic relationships and hence their geographic origins. Here, we use molecular data to reconstruct phylogenetic relationships of the globally distributed butterfly subtribe Coenonymphina (Satyrinae: Satyrini). This group represents a major component of the butterfly fauna of the wider Australasian region, with 19 genera and 71 species endemic to the region. Dating estimates extrapolated from secondary calibration sources indicate that the subtribe arose c. 48 Ma (95% credibility interval, 52–42 Ma), and the crown group first diverged in the Eocene (c. 44 Ma, 95% credibility interval 51–37 Ma). Rapid speciation events subsequently followed around the Eocence–Oligocene boundary, resulting in a near-hard polytomy comprising short basal branches with nodes that are difficult to resolve. Based on strongly supported phylogenetic relationships and estimates of divergence times, we conclude that the group probably had its origin in the fragment of Southern Gondwana consisting of Australia, Antarctica and South America. However, we are unable to rule out the northern dispersal scenario, particularly as Coenonymphina are closely related to a set of predominantly Asian lineages. Dispersal and extinction events following the final break-up of Gondwana have played a pivotal role in shaping the extant distributions of the group.
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13.
  • Kodandaramaiah, Ullasa, et al. (författare)
  • Phylogenetics and biogeography of a spectacular Old World radiation of grass feeding butterflies: the subtribe Mycalesina (Lepidoptera: Nymphalidae: Satyrini)
  • 2010
  • Ingår i: BMC Evolutionary Biology. - : Springer Science and Business Media LLC. - 1471-2148. ; 10, s. 172-185
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Butterflies of the subtribe Mycalesina (Nymphalidae: Satyrinae) are important model organisms in ecology and evolution. This group has radiated spectacularly in the Old World tropics and presents an exciting opportunity to better understand processes of invertebrate rapid radiations. However, the generic-level taxonomy of the subtribe has been in a constant state of flux, and relationships among genera are unknown. There are six currently recognized genera in the group. Mycalesis, Lohora and Nirvanopsis are found in the Oriental region, the first of which is the most speciose genus among mycalesines, and extends into the Australasian region. Hallelesis and Bicyclus are found in mainland Africa, while Heteropsis is primarily Madagascan, with a few species in Africa. We infer the phylogeny of the group with data from three genes (total of 3139 bp) and use these data to reconstruct events in the biogeographic history of the group. Results: The results indicate that the group Mycalesina radiated rapidly around the Oligocene-Miocene boundary. Basal relationships are unresolved, but we recover six well-supported clades. Some species of Mycalesis are nested within a primarily Madagascan clade of Heteropsis, while Nirvanopsis is nested within Lohora. The phylogeny suggests that the group had its origin either in Asia or Africa, and diversified through dispersals between the two regions, during the late Oligocene and early Miocene. The current dataset tentatively suggests that the Madagascan fauna comprises two independent radiations. The Australasian radiation shares a common ancestor derived from Asia. We discuss factors that are likely to have played a key role in the diversification of the group. Conclusions: We propose a significantly revised classification scheme for Mycalesina. We conclude that the group originated and radiated from an ancestor that was found either in Asia or Africa, with dispersals between the two regions and to Australasia. Our phylogeny paves the way for further comparative studies on this group that will help us understand the processes underlying diversification in rapid radiations of invertebrates.
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14.
  • Kodandaramaiah, Ullasa, et al. (författare)
  • Phylogenetics of Coenonymphina (Nymphalidae Satyrinae) and the problem of rooting rapid radiations
  • 2010
  • Ingår i: Molecular Phylogenetics and Evolution. - : Elsevier BV. - 1055-7903 .- 1095-9513. ; 54:2, s. 386-394
  • Tidskriftsartikel (refereegranskat)abstract
    • We report a rapid radiation of a group of butterflies within the family Nymphalidae and examine some aspects of popular analytical methods in dealing with rapid radiations. We attempted to infer the phylogeny of butterflies belonging to the subtribe Coenonymphina sensu lato using five genes (4398bp) with Maximum Parsimony, Maximum Likelihood and Bayesian analyses. Initial analyses suggested that the group has undergone rapid speciation within Australasia. We further analyzed the dataset with different outgroup combinations the choice of which had a profound effect on relationships within the ingroup. Modelling methods recovered Coenonymphina as a monophyletic group to the exclusion of Zipaetis and Orsotriaena, irrespective of outgroup combination. Maximum Parsimony occasionally returned a polyphyletic Coenonymphina, with Argyronympha grouping with outgroups, but this was strongly dependent on the outgroups used. We analyzed the ingroup without any outgroups and found that the relationships inferred among taxa were different from those inferred when either of the outgroup combinations was used, and this was true for all methods. We also tested whether a hard polytomy is a better hypothesis to explain our dataset, but could not find conclusive evidence. We therefore conclude that the major lineages within Coenonymphina form a near-hard polytomy with regard to each other. The study highlights the importance of testing different outgroups rather than using results from a single outgroup combination of a few taxa, particularly in difficult cases where basal nodes appear to receive low support. We provide a revised classification of Coenonymphina; Zipaetis and Orsotriaena are transferred to the tribe Eritina.
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15.
  • Kodandaramaiah, Ullasa, et al. (författare)
  • Phylogeny and biogeography of Coenonympha butterflies (Nymphalidae: Satyrinae) – patterns of colonization in the Holarctic
  • 2009
  • Ingår i: Systematic Entomology. - : Wiley. - 0307-6970 .- 1365-3113. ; 34:2, s. 315-323
  • Tidskriftsartikel (refereegranskat)abstract
    • We studied the historical biogeography of a group of butterflies in the Holarctic region belonging to the genus Coenonympha (Nymphalidae: Satyrinae: Coenonymphina), based on a phylogenetic hypothesis estimated from three genes. The genus is distributed mainly in the Palaearctic region, with two species extending into the Nearctic region. The tree is generally well supported and shows that Coenonympha is paraphyletic with respect to Lyela (syn.n.) and Triphysa (syn.n.), and we hence synonymize the latter two with Coenonympha. Within Coenonympha we identify three species groups, the tullia, glycerion and hero groups. The North American tullia exemplars are not sister to the Eurasian ones. A diva analysis indicates that the ancestor of the group was present in the Central Palaearctic or Central Palaeartic + Western Palaearctic or Central Palaearctic + Eastern Palaearctic. We conclude that the most likely origin of extant members of Coenonympha was in the Central Asian mountains. The tullia and hero groups started diverging in Europe following dispersal into the region. There have been two independent colonizations into Africa. The drying up of the Mediterranean during the Messinian period probably played an important role, allowing colonization into the Mediterranean islands and Africa.
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16.
  • Kodandaramaiah, Ullasa, et al. (författare)
  • Phylogeography of the threatened butterfly, the woodland brown Lopinga achine (Nymphalidae Satyrinae) : implications for conservation
  • 2012
  • Ingår i: Journal of Insect Conservation. - : Springer Science and Business Media LLC. - 1366-638X .- 1572-9753. ; 16:2, s. 305-313
  • Tidskriftsartikel (refereegranskat)abstract
    • We have studied the phylogeography of the red-listed Palearctic butterfly Lopinga achine (Nymphalidae: Satyrinae) based on 1,450 base pairs of mitochondrial DNA sequences from 86 individuals representing 12 populations. Our results indicate a strong structuring of genetic variation, with among-population differences accounting for ca. 67% of the variation and almost all populations being significantly differentiated from each other. We surmise that the insular nature of populations as well as the low dispersal ability of the species has given rise to such a pattern. The genetic diversity within populations is low compared to that in other butterflies. Our results point to a scenario where the species originated in the Eastern Palearctic and expanded into Europe. Based on the analyses, we suggest that the Czech population merits the highest conservation priority. The two Swedish populations represent a distinct evolutionary lineage, and hence merit high conservation attention. The Estonian and Asian populations had the highest genetic diversity, and although we do not consider them to be under immediate threat, their genetic diversity should be conserved in the long term.
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17.
  • Kodandaramaiah, Ullasa, et al. (författare)
  • Population structure in relation to host-plant ecology and Wolbachia infestation in the comma butterfly
  • 2011
  • Ingår i: Journal of Evolutionary Biology. - : Wiley. - 1010-061X .- 1420-9101. ; 24:10, s. 2173-2185
  • Tidskriftsartikel (refereegranskat)abstract
    • Experimental work on Polygonia c-album, a temperate polyphagous butterfly species, has shown that Swedish, Belgian, Norwegian and Estonian females are generalists with respect to host-plant preference, whereas females from UK and Spain are specialized on Urticaceae. Female preference is known to have a strong genetic component. We test whether the specialist and generalist populations form respective genetic clusters using data from mitochondrial sequences and 10 microsatellite loci. Results do not support this hypothesis, suggesting that the specialist and generalist traits have evolved more than once independently. Mitochondrial DNA variation suggests a rapid expansion scenario, with a single widespread haplotype occurring in high frequency, whereas microsatellite data indicate strong differentiation of the Moroccan population. Based on a comparison of polymorphism in the mitochondrial data and sequences from a nuclear gene, we show that the diversity in the former is significantly less than that expected under neutral evolution. Furthermore, we found that almost all butterfly samples were infected with a single strain of Wolbachia, a maternally inherited bacterium. We reason that indirect selection on the mitochondrial genome mediated by a recent sweep of Wolbachia infection has depleted variability in the mitochondrial sequences. We also surmise that P. c-album could have expanded out of a single glacial refugium and colonized Morocco recently.
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18.
  • Kodandaramaiah, Ullasa (författare)
  • Tectonic calibrations in molecular dating
  • 2011
  • Ingår i: Current Zoology. ; 57:1, s. 116-124
  • Tidskriftsartikel (refereegranskat)abstract
    • Molecular dating techniques require the use of calibrations, which are usually fossil or geological vicariance-based. Fossil calibrations have been criticised because they result only in minimum age estimates. Based on a historical biogeographic perspective, I suggest that vicariance-based calibrations are more dangerous. Almost all analytical methods in historical biogeography are strongly biased towards inferring vicariance, hence vicariance identified through such methods is unreliable. Other studies, especially of groups found on Gondwanan fragments, have simply assumed vicariance. Although it was previously believed that vicariance was the predominant mode of speciation, mounting evidence now indicates that speciation by dispersal is common, dominating vicariance in several groups. Moreover, the possibility of speciation having occurred before the said geological event cannot be precluded. Thus, geological calibrations can under- or overestimate times, whereas fossil calibrations always result in minimum estimates. Another major drawback of vicariant calibrations is the problem of circular reasoning when the resulting estimates are used to infer ages of biogeographic events. I argue that fossil-based dating is a superior alternative to vicariance, primarily because the strongest assumption in the latter, that speciation was caused by the said geological process, is more often than not the most tenuous. When authors prefer to use a combination of fossil and vicariant calibrations, one suggestion is to report results both with and without inclusion of the geological constraints. Relying solely on vicariant calibrations should be strictly avoided.
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19.
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20.
  • Kodandaramaiah, Ullasa, 1981- (författare)
  • The dispersal–vicariance pendulum and butterfly biogeography
  • 2009
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • The relative importance of dispersal and vicariance in speciation is a subject of long standing debate. The earliest historical biogeographers invoked dispersal to explain disjunct distributions. With the advent of phylogenetic systematics and the acceptance of plate-tectonic theory, vicariance gained prominence and dispersalist explanations were increasingly rejected in favour of the former. This led to a new paradigm termed ‘vicariance biogeography’. The quintessence of vicariance biogeography is the consideration of vicariance as the null hypothesis in explanations of disjunct distributions. The notion of vicariance being the predominant force in allopatric speciation started gaining increasing acceptance in the biogeographic community. This also came to be reflected in analytical methods, many of which are biased towards vicariant inferences. However, the recent past has seen this vicariance-dominated view being confronted by a suite of studies demonstrating that dispersal has played a vital role in speciation and is equally important, if not more. In this thesis, I have studied the historical biogeography of nymphalid butterflies (Family Nymphalidae) in the genus Junonia and two subtribes - Coenonymphina and Mycalesina. Junonia is found in all major zoogeographic regions apart from the Palaearctic. Coenonymphina is found in the Holarctic, Neotropical and Australasian regions. Mycalesina is found all over the Old World tropics. The results in the thesis indicate that dispersal has played a crucial role in the diversification of these groups, while there is little evidence for vicariance in any group. I also critique Dispersal-Vicariance analysis, the widely used analytical method in historical biogeography that is based on the principle of parsimony. I use simulated data to highlight various sources of error when using the method, and suggest ways that may help increase the realism of biogeographic inferences.
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21.
  • Kodandaramaiah, Ullasa (författare)
  • The evolutionary significance of butterfly eyespots
  • 2011
  • Ingår i: Behavioral Ecology. - : Oxford University Press (OUP). - 1045-2249 .- 1465-7279. ; 22:6, s. 1264-1271
  • Tidskriftsartikel (refereegranskat)abstract
    • Numerous butterflies have circular patterns called eyespots on their wings. Explanations for their functional value have until recently remained hypothetical. However, several studies in the last few years have supported long-standing hypotheses, and the current paper reviews these recent advances. Large and conspicuous eyespots are thought to be effective by being intimidating to predators and thus reducing predation. This hypothesis has received strong support in different studies. It has been shown that eyespots are intimidating because of their conspicuousness, but experimental support for the idea that eyespots are effective by mimicking vertebrate eyes is at the moment lacking. Studies have also tested the deflection hypothesis, where smaller marginal eyespots are thought to deflect attacks away from the body of the prey, increasing chances of survival with a torn wing. Despite previous negative results, recent work has shown that eyespots can indeed deflect attacks toward themselves under specific conditions. Furthermore, data show that dorsal eyespots are used by males and females as signals during courtship. How the diversity in ventral eyespot patterning has evolved remains a mystery. Future directions and further challenges in understanding the adaptive value of eyespots are discussed.
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22.
  • Kodandaramaiah, Ullasa, 1981- (författare)
  • Use of dispersal–vicariance analysis in biogeography – a critique
  • 2010
  • Ingår i: Journal of Biogeography. - 0305-0270 .- 1365-2699. ; 37, s. 3-11
  • Tidskriftsartikel (refereegranskat)abstract
    • Aim Analytical methods are commonly used to identify historical processes of vicariance and dispersal in the evolution of taxa. Currently, dispersal-vicariance analysis implemented in the software diva is the most widely used method. Despite some recognized shortcomings of the method, it has been treated as error-free in many cases and used extensively as the sole method to reconstruct histories of taxa. In light of this, an evaluation of the limitations of the method is needed, especially in relation to several newer alternatives. Methods In an approach similar to simulation studies in phylogenetics, I use hypothetical taxa evolving in specific geological scenarios and test how well diva reconstructs their histories. Results diva reconstructs histories accurately when evolution has been simple; that is, where speciation is driven mainly by vicariance. Ancestral areas are wrongly identified under several conditions, including complex patterns of dispersals and within-area speciation events. Several potentially serious drawbacks in using diva for inferences in biogeography are discussed. These include the inability to distinguish between contiguous range expansions and across-barrier dispersals, a low probability of invoking extinctions, incorrect constraints set on the maximum number of areas by the user, and analysing the ingroup taxa without sister groups. Main conclusions Most problems with inferences based on diva are linked to the inflexibility and simplicity of the assumptions used in the method. These are frequently invalid, resulting in spurious reconstructions. I argue that it might be dangerous to rely solely on diva optimization to infer the history of a group. I also argue that diva is not ideally suited to distinguishing between dispersal and vicariance because it cannot a priori take into account the age of divergences relative to the timing of barrier formation. I suggest that other alternative methods can be used to corroborate the findings in diva, increasing the robustness of biogeographic hypotheses. I compare some important alternatives and conclude that model-based approaches are promising.  
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23.
  • Kodandaramaiah, Ullasa (författare)
  • Vagility - the neglected component in historical biogeography
  • 2009
  • Ingår i: Evolutionary biology. - New York : Springer. - 0071-3260 .- 1934-2845. ; 36:3, s. 327-335
  • Tidskriftsartikel (refereegranskat)abstract
    • The conceptual gap between ecological and historical biogeography is wide, although both disciplines are concerned with explaining how distributions have been shaped. A central aim of modern historical biogeography is to use a phylogenetic framework to reconstruct the geographic history of a group in terms of dispersals and vicariant events, and a number of analytical methods have been developed to do so. To date the most popular analytical methods in historical biogeography have been parsimony-based. Such methods can be classified into two groups based on the assumptions used. The first group assumes that vicariance between two areas creates common patterns of disjunct distributions across several taxa whereas dispersals and extinctions generate clade specific patterns. The second group of methods assumes that passive vicariance and within-area speciation have a higher probability of occurrence than active dispersal events and extinction. Typically, none of these methods takes into account the ecology of the taxa in question. I discuss why these methods can be potentially misleading if the ecology of the taxon is ignored. In particular, the vagility or dispersal ability of taxa plays a pivotal role in shaping the distributions and modes of speciation. I argue that the vagility of taxa should be explicitly incorporated in biogeographic analyses. Likelihood-based methods with models in which more realistic probabilities of dispersal and modes of speciation can be specified are arguably the way ahead. Although objective quantification will pose a challenge, the complete ignorance of this vital aspect, as has been done in many historical biogeographic analyses, can be dangerous. I use worked examples to show a simple way of utilizing such information, but better methods need to be developed to more effectively use ecological knowledge in historical biogeography.
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24.
  • Kodandaramaiah, Ullasa, et al. (författare)
  • Validity of the subspecies paradigm - a case study of the nymphalid butterfly Polygonia faunus
  • Ingår i: PLOS ONE. - 1932-6203.
  • Tidskriftsartikel (refereegranskat)abstract
    • Subspecies are commonly used taxonomic units to formally describe intraspecific geographic variation in morphological traits. However, the concept of subspecies is not clearly defined, and there is little agreement about what they represent in terms of evolutionary units, and whether they can be used as reliably useful units in conservation, evolutionary theory and taxonomy. Although the validity of subspecies has been tested using a multi-marker genetic approach in vertebrates, such studies have been rare in invertebrates. We here test the validity of well-characterized subspecies in the butterfly Polygonia faunus using a combination of mitochondrial sequences and eight microsatellites. We have also investigated the phylogeographic Structure of P. faunus and test whether similarities in host-plant use among populations is related to genetic similarity. Neither the nuclear nor the mitochondrial dataset corroborated subspecies groupings. We found three welldefined genetic clusters corresponding to California, Arizona and (New Mexico + Colorado). There was little structuring among the remaining populations, probably due to gene flow across populations. We found no support for the hypothesis that similarities in host use are related to genetic proximity. The results indicate that the species underwent a recent rapid expansion, probably from two glacial refugia in western North America. The mitochondrial haplotype network indicates at least two independent expansion phases into eastern North America. Ourresults clearly demonstrate that subspecies in P. faunus do not conform to the structuring of genetic variation. More studies on insects and other invertebrates are needed to understand how widespread this phenomenon is. Results in this study will be crucial in designing further experiments to understand the evolution of host plant utilization in this species.
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25.
  • Merilaita, Sami, et al. (författare)
  • Number of eyespots and their intimidating effect on naive predators in the peacock butterfly
  • 2011
  • Ingår i: Behavioral Ecology. - : Oxford University Press (OUP). - 1045-2249 .- 1465-7279. ; 22:6, s. 1326-1331
  • Tidskriftsartikel (refereegranskat)abstract
    • Predation experiments have shown that the large eyespots (concentric rings of contrasting colors) found on the wings of several lepidopteran species intimidate passerine predators. According to the eye mimicry hypotheses, the intimidation is caused by predators associating the eyespots with the presence (of the eyes) of their own enemy. The conspicuousness hypothesis suggests, instead, that it is simply the conspicuousness of eyespot patterns that is intimidating, possibly due to a sensory bias. We studied how the number of eyespots, 2 or 4, influences intimidation. We predicted that if eye mimicry is important, the maximum response would be reached with a pair of eyespots. On the other hand, if conspicuousness is important, then more than 2 eyespots should result in an even stronger response. The peacock butterfly, Inachis io, has 4 large eyespots on its wings. We presented naive insectivorous birds (pied flycatcher, Ficedula hypoleuca) 2 different prey items made from wings of dead peacock butterflies and a mealworm between the wings. One group of birds received prey that had no or only 2 eyespots visible and the other group received prey that had no or all 4 eyespots visible. Eyespots clearly increased hesitation before attacks. Because the birds were naive, this difference in response to the eyespots was innate. Importantly, there was no difference in attack latency between 2 and 4 eyespots. We conclude that it is unlikely that conspicuousness as such has selected for eyespots in the peacock butterfly.
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26.
  • Molleman, Freerk, et al. (författare)
  • Quantifying the effects of species traits on predation risk in nature : A comparative study of butterfly wing damage
  • 2020
  • Ingår i: Journal of Animal Ecology. - : Wiley. - 0021-8790 .- 1365-2656. ; 89:3, s. 716-729
  • Tidskriftsartikel (refereegranskat)abstract
    • Evading predators is a fundamental aspect of the ecology and evolution of all prey animals. In studying the influence of prey traits on predation risk, previous researchers have shown that crypsis reduces attack rates on resting prey, predation risk increases with increased prey activity, and rapid locomotion reduces attack rates and increases chances of surviving predator attacks. However, evidence for these conclusions is nearly always based on observations of selected species under artificial conditions. In nature, it remains unclear how defensive traits such as crypsis, activity levels and speed influence realized predation risk across species in a community. Whereas direct observations of predator–prey interactions in nature are rare, insight can be gained by quantifying bodily damage caused by failed predator attacks. We quantified how butterfly species traits affect predation risk in nature by determining how defensive traits correlate with wing damage caused by failed predation attempts, thereby providing the first robust multi-species comparative analysis of predator-induced bodily damage in wild animals. For 34 species of fruit-feeding butterflies in an African forest, we recorded wing damage and quantified crypsis, activity levels and flight speed. We then tested for correlations between damage parameters and species traits using comparative methods that account for measurement error. We detected considerable differences in the extent, location and symmetry of wing surface loss among species, with smaller differences between sexes. We found that males (but not females) of species that flew faster had substantially less wing surface loss. However, we found no correlation between cryptic coloration and symmetrical wing surface loss across species. In species in which males appeared to be more active than females, males had a lower proportion of symmetrical wing surface loss than females. Our results provide evidence that activity greatly influences the probability of attacks and that flying rapidly is effective for escaping pursuing predators in the wild, but we did not find evidence that cryptic species are less likely to be attacked while at rest.
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27.
  • Peña, Carlos, et al. (författare)
  • Higher level phylogeny of Satyrinae butterflies (Lepidoptera: Nymphalidae) based on DNA sequence data
  • 2006
  • Ingår i: Molecular Phylogenetics and Evolution. - : Elsevier BV. - 1055-7903 .- 1095-9513. ; 40:1, s. 29-49
  • Tidskriftsartikel (refereegranskat)abstract
    • We have inferred the first empirically supported hypothesis of relationships for the cosmopolitan butterfly subfamily Satyrinae. We used 3090 base pairs of DNA from the mitochondrial gene COI and the nuclear genes EF-1alpha and wingless for 165 Satyrinae taxa representing 4 tribes and 15 subtribes, and 26 outgroups, in order to test the monophyly of the subfamily and elucidate phylogenetic relationships of its major lineages. In a combined analysis, the three gene regions supported an almost fully resolved topology, which recovered Satyrinae as polyphyletic, and revealed that the current classification of suprageneric taxa within the subfamily is comprised almost completely of unnatural assemblages. The most noteworthy findings are that Manataria is closely related to Melanitini; Palaeonympha belongs to Euptychiina; Oressinoma, Orsotriaena and Coenonympha group with the Hypocystina; Miller's (1968). Parargina is polyphyletic and its components group with multiple distantly related lineages; and the subtribes Elymniina and Zetherina fall outside the Satyrinae. The three gene regions used in a combined analysis prove to be very effective in resolving relationships of Satyrinae at the subtribal and tribal levels. Further sampling of the taxa closely related to Satyrinae, as well as more extensive sampling of genera within the tribes and subtribes for this group will be critical to test the monophyly of the subfamily and establish a stronger basis for future biogeographical and evolutionary studies.
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28.
  • Sahoo, Ranjit Kumar, et al. (författare)
  • Evolution of Hypolimnas butterflies (Nymphalidae) : Out-of-Africa origin and Wolbachia-mediated introgression
  • 2018
  • Ingår i: Molecular Phylogenetics and Evolution. - : Elsevier BV. - 1055-7903. ; 123, s. 50-58
  • Tidskriftsartikel (refereegranskat)abstract
    • Hypolimnas butterflies (Nymphalidae), commonly known as eggflies, are a popular model system for studying a wide range of ecological questions including mimicry, polymorphism, wing pattern evolution, and Wolbachia-host interactions. The lack of a time-calibrated phylogeny for this group has precluded understanding its evolutionary history. We reconstruct a species-level phylogeny using a nine gene dataset and estimate species divergence times. Based on the resulting tree, we investigate the taxon's historical biogeography, examine the evolution of host plant preferences, and test the hypothesis that the endosymbiotic bacterium Wolbachia mediates gene transfer between species. Our analyses indicate that the species are grouped within three strongly supported, deeply divergent clades. However, relationships among these three clades are uncertain. In addition, many Hypolimnas species are not monophyletic or monophyletic with weak support, suggesting widespread incomplete lineage sorting and/or introgression. Biogeographic analysis strongly indicates that the genus diverged from its ancestor in Africa and subsequently dispersed to Asia; the strength of this result is not affected by topological uncertainties. While the larvae of African species feed almost exclusively on Urticaceae, larvae of species found further east often feed on several additional families. Interestingly, we found an identical mitochondrial haplotype in two Hypolimnas species, H. bolina and H. alimena, and a strong association between this mitotype and the Wolbachia strain wBol1a. Future investigations should explore the plausibility of Wolbachia-mediated introgression between species.
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29.
  • Sahoo, Ranjit Kumar, et al. (författare)
  • Ten genes and two topologies : An exploration of higher relationships in skipper butterflies (Hesperiidae)
  • 2016
  • Ingår i: PeerJ. - : PeerJ. - 2167-8359. ; 2016:12
  • Tidskriftsartikel (refereegranskat)abstract
    • Despite multiple attempts to infer the higher-level phylogenetic relationships of skipper butterflies (Family Hesperiidae), uncertainties in the deep clade relationships persist. The most recent phylogenetic analysis included fewer than 30% of known genera and data from three gene markers. Here we reconstruct the higher-level relationships with a rich sampling of ten nuclear and mitochondrial markers (7,726 bp) from 270 genera and find two distinct but equally plausible topologies among subfamilies at the base of the tree. In one set of analyses, the nuclear markers suggest two contrasting topologies, one of which is supported by the mitochondrial dataset. However, another set of analyses suggests mito-nuclear conflict as the reason for topological incongruence. Neither topology is strongly supported, and we conclude that there is insufficient phylogenetic evidence in the molecular dataset to resolve these relationships. Nevertheless, taking morphological characters into consideration, we suggest that one of the topologies is more likely.
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30.
  • Vallin, Adrian, et al. (författare)
  • Deflective effect and the effect of prey detectability on anti-predator function of eyespots
  • 2011
  • Ingår i: Behavioral Ecology and Sociobiology. - : Springer Science and Business Media LLC. - 0340-5443 .- 1432-0762. ; 65:8, s. 1629-1636
  • Tidskriftsartikel (refereegranskat)abstract
    • Eyespots (patterns of roughly concentric rings) are often thought to have an anti-predator function. Previous experiments have lent support for the intimidation hypothesis by demonstrating a deterring effect of eyespots, but so far there is little evidence for the deflective effect (direction of attacks toward less vital body parts). We studied predators' responses towards large and small eyespots and towards prey with no, one, or a pair of eyespots and if this response is influenced by whether or not prey blend into background. In two experiments, we used artificial, triangular prey items and blue tits (Cyanistes caeruleus) as predators. In experiment 1, we found evidence for the deflective effect of small but not large eyespots, independent of whether the prey was presented on a concealing or exposing background. In experiment 2, we found that predators avoided the prey with a pair of small eyespots more than the prey without eyespots, but interestingly, we only found this deterring effect on the concealing background. There was no difference in attacks between the prey with one large and two small or one large and no eyespots. We conclude that deflective function may select for eyespots, and background may influence the deterring function of eyespots.
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31.
  • Wahlberg, Niklas, et al. (författare)
  • Nymphalid butterflies diversify following near demise at the Cretaceous/Tertiary boundary.
  • 2009
  • Ingår i: Proceedings of the Royal Society of London. Biological Sciences. - : The Royal Society. - 0962-8452 .- 1471-2954. ; 276:1677, s. 4295-4302
  • Tidskriftsartikel (refereegranskat)abstract
    • The butterfly family Nymphalidae contains some of the most important non-drosophilid insect model systems for evolutionary and ecological studies, yet the evolutionary history of the group has remained shrouded in mystery. We have inferred a robust phylogenetic hypothesis based on sequences of 10 genes and 235 morphological characters for exemplars of 400 of the 540 valid nymphalid genera representing all major lineages of the family. By dating the branching events, we infer that Nymphalidae originated in the Cretaceous at 90 Ma, but that the ancestors of 10-12 lineages survived the end-Cretaceous catastrophe in the Neotropical and Oriental regions. Patterns of diversification suggest extinction of lineages at the Cretaceous/Tertiary boundary (65 Ma) and subsequent elevated speciation rates in the Tertiary.
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