Julia Klaczko | Universidade de Brasília - UnB (original) (raw)

Papers by Julia Klaczko

Canadian Journal of Zoology, Nov 11, 2021

Phenotypic plasticity has been described for morphological and life-history traits in many organi... more Phenotypic plasticity has been described for morphological and life-history traits in many organisms. In Drosophila, temperature drives phenotypic change in several traits, but few neotropical species have been studied and whether the phenotypic variation associated with plasticity is adaptive remains unclear. Here, we studied the phenotypic response to temperature variation in the distant related neotropical species Drosophila mercatorum (Patterson and Wheeler, 1942) and Drosophila willistoni (Sturtevant, 1916). We evaluate if wing shape variation follows that observed in the neotropical species Drosophila cardini (Sturtevant, 1916): round wings at lower temperatures and narrower wings at higher temperatures. The variation in egg-adult development time and wing size, shape, and allometry was described using reaction norms and geometric morphometrics. In both species, development time and wing size decreased with increasing temperature and wing allometry showed that size explained ≈10% of the shape variation. Wing shape, however, exhibited contrasting responses. At higher temperatures, D. mercatorum developed slightly slender wings, following the pattern previously found for D. cardini, while D. willistoni developed plumper and shorter wings, supporting previous studies on Drosophila melanogaster (Meigen, 1830). We conclude that all traits studied here were influenced by temperature, and that wing shape seems also to be influenced by phylogeny.

Ethology Ecology & Evolution, Aug 9, 2022

Zoomorphology, Nov 23, 2020

Scolecophidia (Squamata, Serpentes), commonly known as blindsnakes, wormsnakes or threadsnakes co... more Scolecophidia (Squamata, Serpentes), commonly known as blindsnakes, wormsnakes or threadsnakes comprises a group of small snakes, with relatively few systematic and morphological studies when compared to Alethinophidia. Since the external morphology is very conserved amongst scolecophidians, internal morphological studies-such as the hemipenial morphology-are useful to unravel several systematic issues within the group. We aimed to describe the hemipenial morphology of Epictia vellardi (Epictinae, Leptotyphlopidae) based on 16 organs belonging to eight specimens. The organ is unilobed, with the body conspicuously narrower than the base and with the apex slightly expanded, without any macroscopic ornamentation. The comparison of the hemipenial morphology of E. vellardi with other hemipenes of Epictia spp. allowed us to identify two general morphological patterns for the genus, which are proposed and discussed in detail in the present study. The results found herein may be extremely relevant for future hemipenial descriptions. In addition, independent characters found in Types I and II (such as ornamentation, shape of base, body and apex) should be regarded for future systematic and evolutionary morphology studies within Leptotyphlopidae, in addition to assisting in the taxonomy and identification of species of the genus.

Journal of Zoology, 2015

Male genitalia are thought to be particularly rapidly evolving morphological structures, but ther... more Male genitalia are thought to be particularly rapidly evolving morphological structures, but there have been few quantitative interspecific comparisons between the evolutionary rates of genital and non-genital traits. We characterize the morphology of hemipenes in 25 Caribbean Anolis lizard species, and compare rates of hemipenial evolution to those of traits related to ecology or visual signaling. Using phylogenetically-based comparisons of rates of evolutionary divergence, we show that genital traits evolve more rapidly than non-genital traits in anoles.

Concatenated molecular matri

Journal of Herpetology, Sep 1, 2015

In animals with internal fertilization, the male genitalia often vary greatly, have complex morph... more In animals with internal fertilization, the male genitalia often vary greatly, have complex morphology, and show fast rates of evolution. In studies of the evolution of such male genitalia, static allometric relationships have been used extensively. Static allometry is an intraspecific measure of proportional size of a particular structure with respect to the body size. We examined the static allometric pattern of the genitalia of two allopatric subspecies of a Jamaican Anolis lizard, Anolis grahami grahami and A. grahami aquarum, and compared our findings to observed patterns in nongenitalian traits: limbs and the dewlap. Limb and dewlap traits showed similar allometric slopes, with some variation in the intercept, whereas hemipenial traits showed different slopes. The hemipenial traits of Anolis g. grahami exhibited a statistically significant negative allometry, while A. g. aquarum showed slope values that were not statistically different from isometry. Our results corroborate the idea that genital traits evolve faster than other morphological body traits.

Agradeço a Hussam Zaher pela orientação. Por ter me confiado um projeto tão intrigante e desafiad... more Agradeço a Hussam Zaher pela orientação. Por ter me confiado um projeto tão intrigante e desafiador. Agradeço por seu apoio e acima de tudo por sempre ter acreditado em mim.

Biological Journal of The Linnean Society, Sep 1, 2022

Development determines the range of possible phenotypes that can be produced and exposed to selec... more Development determines the range of possible phenotypes that can be produced and exposed to selection and has a major role in the evolutionary trajectories of species. Nevertheless, development is itself subject to evolutionary forces. Here, we describe differences at the ontogenetic and population levels in head and limb proportions of the invasive gecko Hemidactylus mabouia, to assess the developmental mechanisms and extrinsic forces associated with morphological diversification during colonization of novel habitats. We have found that allometric trajectories of most skeletal traits remain constant throughout postnatal development. Linear morphometric analysis did not find multivariate differences between ontogenetic stages or sexes. When comparing populations, our results showed that the divergence of the corresponding external measures was explained by shifts in the intercept of static allometry curves, indicating that differences arose early in development. Populations aggregated into two morphological groups that did not correspond to the groups formed on the basis of genetic structure. Using two different approaches, we found support for an adaptive hypothesis when comparing observed patterns of morphological variation with that expected under neutral evolutionary models.

PLOS ONE, Feb 17, 2016

<p>Proportion of prey items recorded for xenodontinae snakes; an = anuran amphibians; bi = ... more <p>Proportion of prey items recorded for xenodontinae snakes; an = anuran amphibians; bi = birds; ca = caecilids or amphisbenids; eg = lizard eggs; ew = earthworms; fi = fishes; li = lizards; ma = mammals; mo = mollusks; sn = snakes.</p

Journal of Evolutionary Biology, May 25, 2011

Lecture Notes in Computer Science, 2023

Zenodo (CERN European Organization for Nuclear Research), Jun 5, 2022

Systematics and Biodiversity

Canadian Journal of Zoology, Nov 11, 2021

Phenotypic plasticity has been described for morphological and life-history traits in many organi... more Phenotypic plasticity has been described for morphological and life-history traits in many organisms. In Drosophila, temperature drives phenotypic change in several traits, but few neotropical species have been studied and whether the phenotypic variation associated with plasticity is adaptive remains unclear. Here, we studied the phenotypic response to temperature variation in the distant related neotropical species Drosophila mercatorum (Patterson and Wheeler, 1942) and Drosophila willistoni (Sturtevant, 1916). We evaluate if wing shape variation follows that observed in the neotropical species Drosophila cardini (Sturtevant, 1916): round wings at lower temperatures and narrower wings at higher temperatures. The variation in egg-adult development time and wing size, shape, and allometry was described using reaction norms and geometric morphometrics. In both species, development time and wing size decreased with increasing temperature and wing allometry showed that size explained ≈10% of the shape variation. Wing shape, however, exhibited contrasting responses. At higher temperatures, D. mercatorum developed slightly slender wings, following the pattern previously found for D. cardini, while D. willistoni developed plumper and shorter wings, supporting previous studies on Drosophila melanogaster (Meigen, 1830). We conclude that all traits studied here were influenced by temperature, and that wing shape seems also to be influenced by phylogeny.

Ethology Ecology & Evolution, Aug 9, 2022

Zoomorphology, Nov 23, 2020

Scolecophidia (Squamata, Serpentes), commonly known as blindsnakes, wormsnakes or threadsnakes co... more Scolecophidia (Squamata, Serpentes), commonly known as blindsnakes, wormsnakes or threadsnakes comprises a group of small snakes, with relatively few systematic and morphological studies when compared to Alethinophidia. Since the external morphology is very conserved amongst scolecophidians, internal morphological studies-such as the hemipenial morphology-are useful to unravel several systematic issues within the group. We aimed to describe the hemipenial morphology of Epictia vellardi (Epictinae, Leptotyphlopidae) based on 16 organs belonging to eight specimens. The organ is unilobed, with the body conspicuously narrower than the base and with the apex slightly expanded, without any macroscopic ornamentation. The comparison of the hemipenial morphology of E. vellardi with other hemipenes of Epictia spp. allowed us to identify two general morphological patterns for the genus, which are proposed and discussed in detail in the present study. The results found herein may be extremely relevant for future hemipenial descriptions. In addition, independent characters found in Types I and II (such as ornamentation, shape of base, body and apex) should be regarded for future systematic and evolutionary morphology studies within Leptotyphlopidae, in addition to assisting in the taxonomy and identification of species of the genus.

Journal of Zoology, 2015

Male genitalia are thought to be particularly rapidly evolving morphological structures, but ther... more Male genitalia are thought to be particularly rapidly evolving morphological structures, but there have been few quantitative interspecific comparisons between the evolutionary rates of genital and non-genital traits. We characterize the morphology of hemipenes in 25 Caribbean Anolis lizard species, and compare rates of hemipenial evolution to those of traits related to ecology or visual signaling. Using phylogenetically-based comparisons of rates of evolutionary divergence, we show that genital traits evolve more rapidly than non-genital traits in anoles.

Concatenated molecular matri

Journal of Herpetology, Sep 1, 2015

In animals with internal fertilization, the male genitalia often vary greatly, have complex morph... more In animals with internal fertilization, the male genitalia often vary greatly, have complex morphology, and show fast rates of evolution. In studies of the evolution of such male genitalia, static allometric relationships have been used extensively. Static allometry is an intraspecific measure of proportional size of a particular structure with respect to the body size. We examined the static allometric pattern of the genitalia of two allopatric subspecies of a Jamaican Anolis lizard, Anolis grahami grahami and A. grahami aquarum, and compared our findings to observed patterns in nongenitalian traits: limbs and the dewlap. Limb and dewlap traits showed similar allometric slopes, with some variation in the intercept, whereas hemipenial traits showed different slopes. The hemipenial traits of Anolis g. grahami exhibited a statistically significant negative allometry, while A. g. aquarum showed slope values that were not statistically different from isometry. Our results corroborate the idea that genital traits evolve faster than other morphological body traits.

Agradeço a Hussam Zaher pela orientação. Por ter me confiado um projeto tão intrigante e desafiad... more Agradeço a Hussam Zaher pela orientação. Por ter me confiado um projeto tão intrigante e desafiador. Agradeço por seu apoio e acima de tudo por sempre ter acreditado em mim.

Biological Journal of The Linnean Society, Sep 1, 2022

Development determines the range of possible phenotypes that can be produced and exposed to selec... more Development determines the range of possible phenotypes that can be produced and exposed to selection and has a major role in the evolutionary trajectories of species. Nevertheless, development is itself subject to evolutionary forces. Here, we describe differences at the ontogenetic and population levels in head and limb proportions of the invasive gecko Hemidactylus mabouia, to assess the developmental mechanisms and extrinsic forces associated with morphological diversification during colonization of novel habitats. We have found that allometric trajectories of most skeletal traits remain constant throughout postnatal development. Linear morphometric analysis did not find multivariate differences between ontogenetic stages or sexes. When comparing populations, our results showed that the divergence of the corresponding external measures was explained by shifts in the intercept of static allometry curves, indicating that differences arose early in development. Populations aggregated into two morphological groups that did not correspond to the groups formed on the basis of genetic structure. Using two different approaches, we found support for an adaptive hypothesis when comparing observed patterns of morphological variation with that expected under neutral evolutionary models.

PLOS ONE, Feb 17, 2016

<p>Proportion of prey items recorded for xenodontinae snakes; an = anuran amphibians; bi = ... more <p>Proportion of prey items recorded for xenodontinae snakes; an = anuran amphibians; bi = birds; ca = caecilids or amphisbenids; eg = lizard eggs; ew = earthworms; fi = fishes; li = lizards; ma = mammals; mo = mollusks; sn = snakes.</p

Journal of Evolutionary Biology, May 25, 2011

Lecture Notes in Computer Science, 2023

Zenodo (CERN European Organization for Nuclear Research), Jun 5, 2022

Systematics and Biodiversity

Atlas Fotográfico de Anatomia Comparada de Vertebrados, 2023

Os sistemas nervoso e sensorial são responsáveis por receber, processar e responder a estímulos i... more Os sistemas nervoso e sensorial são responsáveis por receber, processar e responder a estímulos internos e externos. Ambos os sistemas estão intrínsecamente interligados e, portanto, são apresentados conjuntamente neste atlas. Via de regra, aspectos de anatomia topológica do sistema nervoso central serão apresentados anteriormente ao sistema nervoso periférico e, por fim, sistema sensorial. O objetivo dessa obra é contribuir para o conhecimento a respeito da estrutura morfofuncional dos vertebrados, permitindo ao público em geral compreender a complexidade de sua constituição, em uma abordagem comparativa por sistema orgânico. Cabe ressaltar que não foi nosso objetivo esgotar os assuntos em pauta, nem tampouco desenvolver revisão teórica sobre os temas abordados. Essa publicação congrega uma coletânea de preparações e imagens produzidas ao longo de mais de duas décadas de pesquisa e produção de objetos educacionais no Laboratório de Anatomia Comparada de Vertebrados da Universidade de Brasília. A maior representação de grupos como peixes, anfíbios, lagartos, serpentes e mamíferos se justifica pela maior disponibilidade de material e aproveitamento de espécimes originários de projetos de pesquisa com esses grupos.