Research

The energetic perspective of tissue regeneration: a case study of tail re-growth in lizards

The ability to voluntarily shed body parts as a strategy to escape predation is known in a wide range of animals. One of the most studied examples of this defensive tactics is the tail autotomy in lizards. The ability of self-amputation is a highly controlled process and requires specific physiological and morphological adaptations. The other side of autotomy is the capability of the lost part to regenerate. Tail autotomy can happen in any life stage of an individual, but the consequences for young growing individual may dramatically differ from that of adults. This project is focusing on metabolic cost of tail regeneration and its effect on somatic growth.

Research team: Zuzana Starostová, Lukáš Kratochvíl (Charles University, Faculty of Science, Department of Zoology and Department of Ecology), Lumír Gvoždík (Institute of Vertebrate Biology, AS CR, Czech Republic)

Starostová Z., Gvoždík L. & Kratochvíl L.: An energetic perspective on tissue regeneration: the costs of tail autotomy in growing geckos. Comparative Biochemistry and Physiology Part A, 206: 82-86. https://dx.doi.org/10.1016/j.cbpa.2017.01.015

Comparative analysis of evaporative water loss in lizards

Maintaining appropriate water balance is crucial for terrestrial animals and it is closely connected with the ability to colonize various habitats. In squamate reptiles, the major proportion of water loss can be attributed to cutaneous and respiratory water loss. Accordingly, evaporative water loss might be influenced by body size, standard metabolic rate and morphology of scales covering the body. In this project we are examining the association between these traits and evaporative water loss in different gecko species.

Research team: Zuzana Starostová, Martin Hlubeň, Tereza Myslíková, Lukáš Kratochvíl (Charles University, Faculty of Science, Department of Zoology and Department of Ecology), Lumír Gvoždík (Institute of Vertebrate Biology, AS CR, Czech Republic)

Hlubeň M., Kratochvíl L., Gvoždík L. & Starostová Z. (2021). Ontogeny, phylogeny, and mechanisms of adaptive changes in evaporative water loss in geckos. Journal of Evolutionary Biology 34: 1290–1301. https://doi.org/10.1111/jeb.13891

Development of sexual size dimorphism in lizards with focus on the genus Paroedura

Body size is a crucial trait connected to nearly every aspect of animal life and is often sexually dimorphic. Despite its central importance, the proximate mechanisms of intra- and interspecific variability in body size are still not well understood. This project focuses mainly on two related gecko species, Paroedura picta and Paroedura vazimba. The entire genus Paroedura has undergone notable radiation in body size and sexual size dimorphism (SSD). The smallest species, P. androyensis, weighs only up to 2 grams, whereas males of its sister and and syntopically living species, P. picta, can grow to more than 35 grams. Paroedura vazimba reaches a maximum body mass of about 3.5 grams. In this genus, small species like P. vazimba are female-larger, while large species like P. picta are male-larger. The genus follows the pattern known as Rensch's rule, a widespread empirical phenomenon. However, the ultimate and proximate causes of Rensch's rule have not been adequately elucidated. To discover which growth regulators are responsible for the evolutionary variability in SSD direction in the genus Paroedura, resulting in patterns consistent with Rensch's rule and evolutionary shifts between male-biased and female-biased SSD, this project focuses on both male-larger and female-larger species.

Research team: Zuzana Starostová, Brandon Meter, Lukáš Kubička and Lukáš Kratochvíl (Charles University, Faculty of Science, Department of Zoology and Department of Ecology)

Starostová Z., Kubička L. & Kratochvíl L. (2010): Macroevolutionary pattern of sexual size dimorphism in geckos corresponds to intraspecific temperature-induced variation. Journal of Evolutionary Biology 23: 670-677.

Starostová Z., Kubička L., Golinski A. & Kratochvíl L. (2013): Neither male gonadal androgens nor female reproductive costs drive development of sexual size dimorphism in lizards. Journal of Experimental Biology 216: 1872-1880.

Kubička L., Starostová Z. & Kratochvíl L. (2015): Endogenous control of sexual size dimorphism: Gonadal androgens have neither direct nor indirect effect on male growth in a Madagascar ground gecko (Paroedura picta). General and Comparative Endocrinology 224: 274-277.

Kratochvíl L., Kubička L., Vohralík M. & Starostová Z. (2018): Variability in vertebral numbers does not contribute to sexual size dimorphism, interspecific variability, or phenotypic plasticity in body size in geckos (Squamata: Gekkota: Paroedura). Journal of Experimental Zoology A 329: 185-190.

Meter B., Kratochvíl L., Kubička L. & Starostová Z. (2022): Development of male-larger sexual size dimorphism in a lizard: IGF1 peak long after sexual maturity overlaps with pronounced growth in males. Frontiers in Physiology 13: 917460.

Thermal influence on life-history decisions and physiology in ectotherms

In ectotherms, environmental temperature is the most prominent abiotic factor that modulates life-history traits. We use the Madagascar ground gecko (Paroedura picta) to study the influence of environmental temperatures on body size and other life-history and physiological traits such as egg size, growth rate, developmental rate or rate of clutch production. The main goal is to uncover relationships among particular traits within each thermal environment and across temperatures and search for proximate mechanism of life-history strategies such as thermally-specific gene expression, different levels of steroid hormones and differences in energy assimilation and allocation. Studying thermally-induced phenotypic plasticity in can help us to estimate impact of global warming on physiology, life-history and ecology of ectotherms in general.

Research team: Zuzana Starostová, Lukáš Kubička, Lukáš Kratochvíl (Charles University, Faculty of Science, Department of Zoology and Department of Ecology)

Starostová Z., Angilletta M.J., Kubička L. & Kratochvíl L. (2012): Thermal dependence of reproductive allocation in a tropical lizard. Journal of Thermal Biology 37: 159-163.

Kubička L., Starostová Z. & Kratochvíl L. (2012): Temperature-dependent rate of clutch production in a tropical lizard (Paroedura picta: Gekkonidae): Intraspecific test of the Metabolic Theory of Ecology. Journal of Thermal Biology 37: 179-184.

Starostová Z., Kubička L. & Kratochvíl L. (2010): Macroevolutionary pattern of sexual size dimorphism in geckos corresponds to intraspecific temperature-induced variation. Journal of Evolutionary Biology 23: 670-677.

Weiser H., Starostová Z., Kubička L. & Kratochvíl L. (2012): Overlap of female reproductive cycles explains shortened interclutch interval in a lizard with invariant clutch size (Squamata: Gekkonidae: Paroedura picta). Physiological and Biochemical Zoology 85: 491-498.

Meter B., Starostová Z., Kubička L. &  Kratochvíl L. (2020): The limits of the energetical perspective: Life-history decisions in lizard growth. Evolutionary Ecology 34: 469–481.

Testing the role of cell size variation in body size changes and intra- and interspecific metabolic allometries

While metabolism is a fundamental feature of all organisms, the causes of its scaling are not yet fully explained. In this project we are trying to uncover the role of cell size (red blood cell size) in shaping of metabolic rate scaling. More specifically, we are studying how variation in red blood cell size on both intra- and interspecific levels affects metabolic rate scaling in a monophyletic group of geckos (family Eublepharidae). These geckos exhibit large variation in body size among species, but we can also find considerable body size variation during ontogeny. So far our results show that variability in cell size could have important physiological consequences, such as a qualitatively different pattern of standard metabolic rate-body mass relationship.

Research team: Zuzana Starostová; Lukáš Kubička, Lukáš Kratochvíl (Charles University, Faculty of Science, Czech Republic); Jan Kozlowski (Institute of Environmental Sciences, Jagiellonian University, Krakow, Poland); Marek Konarzewski (University of Bialystok, Bialystok, Poland)

Starostová Z., Kozlowski J., Konarzewski M. & Kratochvíl L. (2013): Ontogeny of metabolic rate and red blood cell size in eyelid geckos: Species follow different paths. PLoS ONE 8(5): e64715. doi:10.1371/journal.pone.0064715.

Starostová Z., Kubička L., Kozlowski J., Konarzewski M. & Kratochvíl L. (2009): Cell size but not genome size affects scaling of metabolic rate in eyelid geckos. American Naturalist 174: E100-E105. and see Publications and our posters for more details.

Czarnoleski M., Labecka A.M., Starostová Z., Sikorska A., Bonda-Ostaszewska E, Woch K., Kubička L., Kratochvíl L. & Kozlowski J. (2017): Not all cells are equal: temperature and sex effects on the size of different cell types in the Madagascar ground gecko Paroedura picta. Biology Open 6: 1149-1154.
Starostová Z., Kratochvíl L. & Frynta D. (2005): Dwarf and giant geckos from the cellular perspective: The bigger the animal, the bigger its erythrocytes? Functional Ecology 19: 744-749.

Anticoagulant resistance in synanthropic rodents in the Czech Republic

The use of anticoagulant rodenticides to control synanthropic rodent populations, such as mice and rats, in agricultural and urban settings has become increasingly challenging due to the development of resistance. These anticoagulants, crucial for controlling rodent populations without causing immediate bait shyness, are facing efficacy issues as rodents develop genetic mutations that result in resistance. This resistance allows them to withstand typical doses of rodenticides without suffering fatal effects, complicating control efforts and potentially leading to increased environmental and wildlife risks due to the need for higher doses or more frequent applications. Our research aims to monitor and understand the extent and distribution of this resistance to tailor rodent control strategies that are both effective and environmentally sound.

Research team: Zuzana Starostová in collaboration with Marcela Fraňková, Radek Aulický and Václav Stejskal (Crop Research Institute, Prague, Czech Republic)

Fraňková M., Starostová, Z., Aulický R. & Stejskal V. (2024). Rezistence u myši domáci v ČR. Zemědělec 3/2024: 14-16.(in Czech)

Frankova M., Starostova Z., Aulicky R. & Stejskal V. (2025): Widespread anticoagulant resistance in house mice (Mus musculus musculus) linked to the Tyr139Phe mutation in the Czech Republic. Scientific Reports: 15, 1701. https://doi.org/10.1038/s41598-025-85447-8

Perspectives of captive populations of endangered reptiles: Genetic variation in two model species (Epicrates angulifer and Cyclura nubila)

In this project we studied genetic variability in Cuban rock iguana (Cyclura nubila nubila) – belonging to the largest native terrestrial herbivores of the West Indies and Cuban boa (Epicrates angulifer). In order to assess genetic variation in these two species we sequenced fragments of mitochondrial DNA in iguanas and boas from European Zoos and private breeders. The animals sampled represent founders and important representatives of the studbook population. For more details please click on our poster.

Research team: Zuzana Starostová, Ivana Hynková, Daniel Frynta (Charles University, Faculty of Science, Department of Zoology) and Ivan Rehák (Prague ZOO)

Starostová Z., Rehák I. & Frynta D. New haplotypes of Cyclura nubila nubila from Cuba changed the phylogenetic tree of rock iguanas: a challenge for conservation strategies? Amphibia-Reptilia: Amphibia-Reptilia 31:134-143.