Renata Brandt

Universidade de São Paulo, Biologia-FFCLRP, Post-Doc

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Supervisors: Carlos A. Navas

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Lucas Nascimento

Instituto Federal Catarinense Campus Camboriú

Jose Bicudo

Universidade de São Paulo

Wilfried Klein

Universidade de São Paulo

Fábio Barros

Universidade de São Paulo

Ricardo S Bovendorp

Universidade Estadual de Santa Cruz

Michael Rochford

Joseph Wasilewski

Ana Carolina Srbek de Araujo

Universidade Vila Velha

Gisele Winck

Université Grenoble Alpes

Sonia Z Cechin

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Papers by Renata Brandt

18.P1. Eggshell morphology of a Tropidurus lizard: why are poles and hemispheres different?

Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology, 2007

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Sexual differences in locomotor performance in Tropidurus catalanensis lizards (Squamata: Tropiduridae) – body shape, size and limb musculature explain variation between males and females

Sexual dimorphism (SD) is the evolutionary outcome of selection acting differently on males and f... more Sexual dimorphism (SD) is the evolutionary outcome of selection acting differently on males and females. Several studies describe sexual differences in body size, although other morphological traits might be allometric between sexes and imply functional consequences. Here we test whether morphological differences between sexes in size and shape in the lizard Tropidurus catalanensis explain variation in performance of four locomotor traits. Our results show that males are larger than females and also exhibit longer limbs, longer muscles and larger muscle cross-sectional areas, while females have longer trunks and more sharped anterior claws; males outperform females in all locomotor performances measured. Sexual differences in sprinting and climbing is related with body size, and climbing performance is also explained by limb lengths, by differences in lengths and cross-sectional areas of specific muscles, and by interlimb distances. Between-sex differences in exertion are also related to SD, despite associations with sharper posterior claws that are independent of sex. Grasping performance, however, is associated with some muscle and morphological parameters that are not sexually dimorphic. Together our results suggest that morphology might be under sexual selection in T. catalanensis, given that better locomotor performance likely favours male lizards in typical activities of this polygenic species, such as territory defence and female acquisition. Moreover, the longer trunks that characterize females may confer more space to accommodate eggs. On the other hand, territory defence by males probably increases their exposure to predators, resulting in a synergistic effect of sexual and natural selection in the evolution of SD in T. catalanensis.

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Sprint performance of a generalist lizard running ondifferent substrates: grip mattersRenata

by Fabricio Galvani and Renata Brandt

The relationships between locomotor performance and major features of environmental structure, su... more The relationships between locomotor performance and major features of environmental structure, such as incline and diameter, have been consistently identified in several vertebrate groups. The effects of variation in characteristics such as texture and structural complexity, in contrast, remain neglected, and associations between sprint speeds achieved during steady-level locomotion and the way an animal grips
the surface are particularly obscure. In the present study, we have used the habitat generalist lizard Tropidurus torquatus to test the hypothesis that animals run faster on the substrates where gripping performance is higher. We ran 18 individuals on
seven different substrates (wood, thin and coarse sand, coarse gravel, rock, leaf litter and grass) and recorded their maximum speeds using high-speed cameras.
Surfaces were characterized for height variation and grip, the last given by average grip performance achieved by lizards of different sizes. Maximum sprint speeds were highest on rock and grass and lowest on thin and coarse sand, and variation
in performance among substrates was explained by grip: substrates in which lizards gripped stronger are those that enhanced average maximum sprint speed.
This study is the first report providing evidence for variation in maximum sprint speeds achieved by a generalist lizard running on different substrates, and demonstrates how friction resulting from the interaction of the lizard with the substrate may be critically important for sprint speed.

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Sprint performance of a generalist lizard running on different substrates: grip matters

The relationships between locomotor performance and major features of environmental structure, su... more The relationships between locomotor performance and major features of environmental structure, such as incline and diameter, have been consistently identified in several vertebrate groups. The effects of variation in characteristics such as texture and structural complexity, in contrast, remain neglected, and associations between sprint speeds achieved during steady-level locomotion and the way an animal grips the surface are particularly obscure. In the present study, we have used the habitat generalist lizard Tropidurus torquatus to test the hypothesis that animals run faster on the substrates where gripping performance is higher. We ran 18 individuals on seven different substrates (wood, thin and coarse sand, coarse gravel, rock, leaf litter and grass) and recorded their maximum speeds using high-speed cameras. Surfaces were characterized for height variation and grip, the last given by average grip performance achieved by lizards of different sizes. Maximum sprint speeds were highest on rock and grass and lowest on thin and coarse sand, and variation in performance among substrates was explained by grip: substrates in which lizards gripped stronger are those that enhanced average maximum sprint speed. This study is the first report providing evidence for variation in maximum sprint speeds achieved by a generalist lizard running on different substrates, and dem- onstrates how friction resulting from the interaction of the lizard with the sub- strate may be critically important for sprint speed.

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Body size variation across climatic gradients and sexual size dimorphism in Tropidurinae lizards

Journal of Zoology, 2013

In certain lineages of tetrapods, latitude and climate relate to body size in agreement with Berg... more In certain lineages of tetrapods, latitude and climate relate to body size in agreement with Bergmann's rule. Trends for squamates are ambiguous, even between genders within a species. Therefore, additional studies are required before generalizations can be made, and attention is needed to the possibility that male and female experience distinct selective pressures and display different patterns. We examine body size in male and female Tropidurinae lizard species and test both Bergmann's and Rensch's rule, using phylogenetic comparative methods. We also analyze whether trends are better explained by latitude or climatic conditions. In Tropidurinae lizards, body size does not vary in accordance with Bergmann's rule within the range of latitudes studied. Therefore, within this range, tropidurines seem not to experience thermal constraints limiting activity time, and therefore growth and body size. Yet, female body size relates to rain patterns, expectedly linked to productivity, suggesting that this gender experiences a stronger tradeoff between energy allocated to growth and to reproduction. In Tropidurinae, males tend to be larger than females and sexual dimorphism is male biased, with an isometric relationship between both sexes that does not support Rensch's rule.

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Life-History Evolution on Tropidurinae Lizards: Influence of Lineage, Body Size and Climate

PLoS ONE, Jan 1, 2011

The study of life history variation is central to the evolutionary theory. In many ectothermic li... more The study of life history variation is central to the evolutionary theory. In many ectothermic lineages, including lizards, life history traits are plastic and relate to several sources of variation including body size, which is both a factor and a life history trait likely to modulate reproductive parameters. Larger species within a lineage, for example tend to be more fecund and have larger clutch size, but clutch size may also be influenced by climate, independently of body size. Thus, the study of climatic effects on lizard fecundity is mandatory on the current scenario of global climatic change. We asked how body and clutch size have responded to climate through time in a group of tropical lizards, the Tropidurinae, and how these two variables relate to each other. We used both traditional and phylogenetic comparative methods. Body and clutch size are variable within Tropidurinae, and both traits are influenced by phylogenetic position. Across the lineage, species which evolved larger size produce more eggs and neither trait is influenced by temperature components. A climatic component of precipitation, however, relates to larger female body size, and therefore seems to exert an indirect relationship on clutch size. This effect of precipitation on body size is likely a correlate of primary production. A decrease in fecundity is expected for Tropidurinae species on continental landmasses, which are predicted to undergo a decrease in summer rainfall.

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Evolution of Body Elongation in Gymnophthalmid Lizards: Relationships with Climate

The evolution of elongated body shapes in vertebrates has intrigued biologists for decades and is... more The evolution of elongated body shapes in vertebrates has intrigued biologists for decades and is particularly recurrent among squamates. Several aspects might explain how the environment influences the evolution of body elongation, but climate needs to be incorporated in this scenario to evaluate how it contributes to morphological evolution. Climatic parameters include temperature and precipitation, two variables that likely influence environmental characteristics, including soil texture and substrate coverage, which may define the selective pressures acting during the evolution of morphology. Due to development of geographic information system (GIS) techniques, these variables can now be included in evolutionary biology studies and were used in the present study to test for associations between variation in body shape and climate in the tropical lizard family Gymnophthalmidae. We first investigated how the morphological traits that define body shape are correlated in these lizards and then tested for associations between a descriptor of body elongation and climate. Our analyses revealed that the evolution of body elongation in Gymnophthalmidae involved concomitant changes in different morphological traits: trunk elongation was coupled with limb shortening and a reduction in body diameter, and the gradual variation along this axis was illustrated by less-elongated morphologies exhibiting shorter trunks and longer limbs. The variation identified in Gymnophthalmidae body shape was associated with climate, with the species from more arid environments usually being more elongated. Aridity is associated with high temperatures and low precipitation, which affect additional environmental features, including the habitat structure. This feature may influence the evolution of body shape because contrasting environments likely impose distinct demands for organismal performance in several activities, such as locomotion and thermoregulation. The present study establishes a connection between morphology and a broader natural component, climate, and introduces new questions about the spatial distribution of morphological variation among squamates.

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Mudanças climáticas e os lagartos brasileiros sob a perspectiva da história de vida

A história de vida é o resultado de um desafio ecológico imposto pelo ambiente, tenta explicar co... more A história de vida é o resultado de um desafio ecológico imposto pelo ambiente, tenta explicar como a evolução molda os organismos a fim de atingir o sucesso reprodutivo (Stearns, 2000). Sendo assim está intimamente relacionada com as mudanças climáticas em pauta nesta edição especial. Neste artigo são revistos os efeitos de mudanças de temperatura e precipitação em alguns traços fenotípicos de história de vida de lagartos. Ao final, com base no conhecimento atual sobre os lagartos brasileiros e nas previsões de mudanças climáticas para o Brasil, são feitas algumas previsões de mudanças na história de vida dos lagartos. Palavras-chave. Mudanças climáticas, lagartos, história de vida.

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Evolução da viviparidade em Squamata: cenários evolutivos e raridade dos estágios intermediários

A viviparidade em Squamata é derivada da oviparidade e surgiu mais de 100 vezes distintas dentro ... more A viviparidade em Squamata é derivada da oviparidade e surgiu mais de 100 vezes distintas dentro do grupo. Uma das hipóteses que melhor explica esta transição está relacionada aos requerimentos térmicos dos embriões em desenvolvimento. As trocas gasosas e umidade do substrato de incubação, entretanto, também são fatores fundamentais para sobrevivência nos estágios embrionários. Estes últimos fatores, por sua vez, podem ser os responsáveis pela raridade de estágios intermediários de desenvolvimento no momento da postura, uma vez que um compromisso evolutivo entre o prolongamento da retenção uterina e a espessura da casca é claramente identificado.
Palavras-chave. Evolução da viviparidade, Squamata, Estágios de desenvolvimento.

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Aspectos evolutivos da história de vida e estrutura da casca do ovo de lagartos tropiduríneos

18.P1. Eggshell morphology of a Tropidurus lizard: why are poles and hemispheres different?

Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology, 2007

Download

Sexual differences in locomotor performance in Tropidurus catalanensis lizards (Squamata: Tropiduridae) – body shape, size and limb musculature explain variation between males and females

Download

Sprint performance of a generalist lizard running ondifferent substrates: grip mattersRenata

by Fabricio Galvani and Renata Brandt

Download

Sprint performance of a generalist lizard running on different substrates: grip matters

The relationships between locomotor performance and major features of environmental structure, su... more The relationships between locomotor performance and major features of environmental structure, such as incline and diameter, have been consistently identified in several vertebrate groups. The effects of variation in characteristics such as texture and structural complexity, in contrast, remain neglected, and associations between sprint speeds achieved during steady-level locomotion and the way an animal grips the surface are particularly obscure. In the present study, we have used the habitat generalist lizard Tropidurus torquatus to test the hypothesis that animals run faster on the substrates where gripping performance is higher. We ran 18 individuals on seven different substrates (wood, thin and coarse sand, coarse gravel, rock, leaf litter and grass) and recorded their maximum speeds using high-speed cameras. Surfaces were characterized for height variation and grip, the last given by average grip performance achieved by lizards of different sizes. Maximum sprint speeds were highest on rock and grass and lowest on thin and coarse sand, and variation in performance among substrates was explained by grip: substrates in which lizards gripped stronger are those that enhanced average maximum sprint speed. This study is the first report providing evidence for variation in maximum sprint speeds achieved by a generalist lizard running on different substrates, and dem- onstrates how friction resulting from the interaction of the lizard with the sub- strate may be critically important for sprint speed.

Download

Body size variation across climatic gradients and sexual size dimorphism in Tropidurinae lizards

Journal of Zoology, 2013

Download

Life-History Evolution on Tropidurinae Lizards: Influence of Lineage, Body Size and Climate

PLoS ONE, Jan 1, 2011

Download

Evolution of Body Elongation in Gymnophthalmid Lizards: Relationships with Climate

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Mudanças climáticas e os lagartos brasileiros sob a perspectiva da história de vida

Download

Evolução da viviparidade em Squamata: cenários evolutivos e raridade dos estágios intermediários

Download

Aspectos evolutivos da história de vida e estrutura da casca do ovo de lagartos tropiduríneos

Renata Brandt

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