Krzysztof Kowalski

Krzysztof Kowalski
Nicolaus Copernicus University | umk · Department of Vertebrate Zoology and Ecology

PhD

About

20
Publications
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91
Citations
Introduction
I am an Assistant Professor at the Department of Vertebrate Zoology and Ecology, Nicolaus Copernicus University, Toruń, Poland. I do research in Toxicology, Ecology and Zoology. My current projects are 'Function and composition of venom of the water shrew (Neomys fodiens)' and 'Costs of chemical defence in bufonids'.
Education
October 2010 - June 2012
Adam Mickiewicz University
Field of study
  • Environmental Biology
October 2007 - July 2010
Adam Mickiewicz University
Field of study
  • Biology

Publications

Publications (20)
Article
Full-text available
Background: Venom production has evolved independently many times in the animal kingdom, although it is rare among mammals. Venomous shrews produce toxins in their salivary glands and use their venoms to hunt and store prey. Thus far, the toxicity and composition of shrew venoms have been studied only in two shrew species: the northern short-taile...
Article
Full-text available
Venomousness is a complex functional trait that has evolved independently many times in the animal kingdom, although it is rare among mammals. Intriguingly, most venomous mammal species belong to Eulipotyphla (solenodons, shrews). This fact may be linked to their high metabolic rate and a nearly continuous demand of nutritious food, and thus it rel...
Article
Anurans secrete a wide diversity of toxins from skin glands to defend themselves against predators and pathogens. Bufonids produce potent poison in parotoid macroglands located in the postorbital region. Parotoid secretion is a rich source of bioactive compounds with cardiotoxic, cytotoxic and hemolytic activity. Poison content and toxicity may var...
Thesis
Full-text available
Animal toxins have many medical and therapeutic applications. Principally, toxins produced by insects, arachnids, snakes and frogs have been characterized. Mammalian venoms and toad poisons (and especially their protein components) have not been comprehensively investigated so far. Therefore, I analysed composition, toxic properties and functions o...
Article
Being venomous should help a predator to maximize foraging gain, reduce handling time, and hoard food. Shrews are a good model for study of the relationship between venomousness and optimal foraging as they have to be highly efficient foragers (because of extremely high energy requirements) and comprise a few venomous species. We hypothesized that...
Article
European anurans are prey for a variety of predators, against which they have evolved a range of defense behaviors. We investigated defensive behaviors of three European anurans: the Common Toad (Bufo bufo), the Common Frog (Rana temporaria), and the Edible Frog (Pelophylax esculentus) during interactions with a predator (hedgehog) and a control st...
Article
Anuran toxins released from the skin glands are involved in defence against predators and microorganisms. Secretion from parotoid macroglands of bufonid toads is a rich source of bioactive compounds with the cytotoxic, cardiotoxic and hemolytic activity. Bufadienolides are considered the most toxic components of the toad poison, whereas the protein...
Article
Full-text available
Background Animal toxins can have medical and therapeutic applications. Principally, toxins produced by insects, arachnids, snakes and frogs have been characterized. Venomous mammals are rare, and their venoms have not been comprehensively investigated. Among shrews, only the venom of Blarina brevicauda has been analysed so far, and blarina toxin h...
Article
Full-text available
European anurans are prey for a variety of predators, against which they have evolved a range of defense behaviors. We investigated defensive behaviors of three European anurans: the Common Toad (Bufo bufo), the Common Frog (Rana temporaria), and the Edible Frog (Pelophylax esculentus) during interactions with a predator (hedgehog) and a control st...
Article
Full-text available
Jadowitość jest niezwykle rzadkim zjawiskiem wśród ssaków, zarówno tych kopalnych, jak i współczesnych. Niemniej jednak, przypuszcza się, że już niektóre mezozoiczne ssaki mogły być pierwotnie jadowite. Z drugiej jednak strony, zwolennicy przeciwstawnej teorii przekonują, że jadowitość jest nowo nabytą cechą, która u współczesnych Eulipotyphla wyew...
Article
Full-text available
Recognizing patterns of parasite distribution among wildlife hosts is of major importance due to growing risk of transmission of zoonotic diseases to humans. Thus, sex-dependent parasite distribution in higher vertebrates is extensively studied, and males are often found more parasitized than females. Male-biased parasitism may be the result of wea...
Article
Full-text available
Only a few studies comparing flea composition on the coast and in the mountains have been conducted. We investigated differences in flea communities infesting small mammals in selected habitats in northern, central, and southern Poland. We predicted (1) a greater number of flea species in the southeastern Poland and a lower number in the north, (2)...
Article
Full-text available
W niniejszym artykule dokonujemy przeglądu jadowitych ssaków, z uwzględnieniem „swoiście ja¬dowitych” (takich jak należący do rzędu stekowców dziobak australijski i zaliczane do rzędu ryjówko¬kształtnych almiki, ryjówki krótkoogonowe, rzęsorki i jeden gatunek zębiełka), „nieswoiście jadowitych” (nietoperze wampiry) i przypuszczalnie jadowitych (kil...

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Projects

Projects (3)
Project
Anurans secrete a wide diversity of toxins from skin glands to defend themselves against predators and pathogens. Bufonid toads produce potent secretions in parotoid macroglands located in the postorbital region. Parotoid secretion is a rich source of bioactive molecules with cardiotoxic, cytotoxic and hemolytic activity. Poison content and toxicity may vary between species, populations, and among conspecifics inhabiting the same area. We aim to determine causes and consequences of variation in chemical defense (mainly toxicity of parotoid secretion) in common toads Bufo bufo.
Archived project
Among anurans, toxins released by poisonous frogs and toads have been well-studied thus far. It has been proven that anuran toxins act as an anti-predator and antimicrobial weapon. Compounds of the bufonid parotoid secretions have been classified into four main categories: biogenic amines, bufadienolides, alkaloids, and peptides and proteins. Bufadienolides are the most comprehensively investigated components, not only with the respect to the chemical composition, but also to their biological activities. Proteins and peptides are present in the toad poison in very low quantities and the knowledge on their properties is scarce. However, it is highly probable that certain proteins might act synergistically with other compounds (e.g., bufadienolides or biogenic amines) of the toad poison and/or modify (inhibit or reinforce) their toxic effects. Therefore, we analysed composition and properties of proteins and peptides from parotoid secretion of the common toad Bufo bufo. We also studied (in behavioral experiments) the role of the toad poison in avoidance of predator attack.
Project
Many animal toxins have been discovered in the last century and it has been proven that many of them can have medical and therapeutic applications. Principally, toxins produced by insects, arachnids, snakes and frogs have been characterized thus far. Venomous mammals are rare, and their venoms have not been comprehensively investigated. Among shrews, only the venom of the short-tailed shrew Blarina brevicauda has been analysed, and blarina toxin and soricidin have been proven to be its main toxic components. At the end of the 50s and 60s of the last century, Pucek (1959, 1969) discovered that two species of water shrews (Neomys fodiens and N. anomalus) produce in their salivary glands a potent venom that is toxic to mammals such as mice, voles and rabbits. The strongest toxic effects of venom were revealed after intracerebral and intravenous injections. These results, and observations of the food hoarding by the water shrew, led to a conclusion that N. fodiens venom has strong paralytic properties and enables the water shrew hunting and hoarding larger prey, such as fish, newts or frogs. Unfortunately, toxic components of N. fodiens venom were not characterized. Therefore, I analysed composition and properties of venom of the Eurasian water shrew, as well as its role in hunting and hoarding of prey differing in body size by N. fodiens. The research was supported by grant no. 2015/17/N/NZ8/01567 from the National Science Centre, Poland, and, in part, by the budget of the Department of Systematic Zoology (Faculty of Biology, AMU, Poznań).