|
|
Behaviour and electric activity of the Gnathonemus petersii species
Juhaňáková, Kateřina ; Kubáčová Langová, Veronika (advisor) ; Frouzová, Jaroslava (referee)
Peter's elephantnose fish (Gnathonemus petersii) is a remarkable fish of the Mormyridae family. It is set apart by its bizarre appearance and, most of all, its biology. It is one of the weakly electric fish, which are characterised by emitting electric organ discharges (EOD) placed in their caudal peduncle. They recieve and analyze EOD by other electroreceptive organs differing in function and anatomy. EOD provides active and passive electrolocation to the fish as it senses electric fields of nearby objects and animals. During active electrolocation mormyrids emit and simultaneously perceive electric signals, which enables them to analyse nearby objects. They are able to recognize an object's size, shape and material. EOD, intervals between discharges and sequences of intervals are essential in communication. Combined, they are able to transmit information about sex, hierarchy, behavioral status and environment. Other important parts of social communication are vision, olfactory, mechanosensory and auditory systems. This thesis provides an overview of existing knowledge of this species, its electric activity and behaviour. The potential of Gnathonemus petersii as a model organism in neurobiological and neuroethological studies is discussed. Key words: Gnathonemus petersii, electric activity,...
|
|
|
Elephant fishes in pet trade
Habartová, Anna ; Kalous, Lukáš (advisor) ; Kuříková, Pavlína (referee)
This thesis discusses the family Mormyridae and the use of its representatives in the ordinary aquarium. It provides further informations about morphology, physiology and location of the general representatives of the family, and particularly focuses on Gnathonemus petersii, as one of the representatives of the ability electroreception, electrolocation and electrogenezis. Furthermore there are in the text informations about the use of electrical signals such as communication, orientation in space, or the perception of live and lifeless objects and their distribution in space. The work also includes a sociological research about breeding of African fish, which was realized among Czech aquarists.
|
guest ::
