|
|
Responses of naive primates to snakes: experiments with selected species kept in Prague zoo
Kutinová, Lucie ; Frynta, Daniel (advisor) ; Fuchs, Roman (referee)
In the wild, snakes are known to elicit strong antipredator responses in primates. Primates often mob the snakes, which is also accompanied by loud calls. In evolution, the deadly threat posed by snakes goes as far as to the origin of placental mammals. In this study, the reactions of naïve individuals to snakes were tested. Naïve pigtail macaques (Macaca nemestrina) and mouse lemurs (Microcebus murinus) avoided the snake stimulus. For the macaques there was a longer latency to touch the rubber snake compared to the latency to touch the rubber lizard. The mouse lemurs avoided feeding on the side of experimental box where the snake odor was presented. The reactions of macaques and mouse lemurs were not accompanied by vocalizations and they seemed to be overall mild. Nevertheless, the snake stimuli used here were strong enough for these naïve primates. For ringtail lemurs (Lemur catta), the reactions to uncovering a hidden rubber snake was tested. But the lemurs showed no avoiding reactions. A question for further research is whether the different results for lemurs were not caused by different experimental procedure. As well as in macaques and mouse lemurs, the reactions seemed to be very mild. But no deeper analysis of the behavior was performed. Thus, a reaction could have been overlooked, which...
|
|
|
Antipredatory function of flash display in Heteroptera (case of Coreus marginatus)
Pipek, Pavel ; Exnerová, Alice (advisor) ; Kleisner, Karel (referee)
1 Abstract Aim of the present study was to test antipredatory function of fulguration (or flash display), which means sudden exposition of conspicous body part on otherwise cryptic animal during escape. Adult squash bugs (Coreus marginatus; Heteroptera) were used as model prey, while as model predator served two species of passerine birds - blue tit (Cyanistes caerulus) and great tit (Parus major). Three approaches were undertaken. Test of palatability should have assessed the efficiency of squash bug chemical defence against bird predators. Experiment was carried out in experimental cage without interference of experimenter and without occurrence of fulguration. The results show that chemical defense of squash bug is less efficient than defense of other species of true bugs (Pyrrhocoris apterus, Graphosoma lineatum) and that the efficiency differs between two generations of squash bugs. In the test of efficiency of fulguration, the prey was forced by experimenter to fly in response to bird attack. Blue tits attacked the immobile prey more often than the flying and fulgurating one, but the same relation wasn't significant with great tits. The latencies of birds' returns to the bugs that landed after fulguration wasn't influenced by colour of the bugs' abdomen. Third experiment consisted of computer...
|
|
|
Varovná vokalizace pěnice vlašské (\kur{Sylvia nisoria})
SÝKOROVÁ, Jana
Alarm calls are one of the essential components of antipredator behaviour in birds. In this study I recorded and analysed alarm responses of the barred warbler (Sylvia nisoria) to different mounts of avian predators and nonpredators. The information about danger is encoded through graded structure in its unspecific alarm call type.
|
|
|
Antipredační chování pěnice vlašské (\kur{Sylvia nisoria})
BURŠÍKOVÁ, Markéta
My study was aimed to describe the antipredator behaviour of Barred Warbler against five avian mounted dummies differing in the level of threat they represent for the Barred Warbler: Eurasian Sparrowhawk (Accipiter nisus), Eurasian Jay (Garrulus glandarius), Black-billed Magpie (Pica pica), Red-backed Shrike (Lanius collurio), and Domastic Pigeon (Columba livia f. domestica) using the experiments carried in the vicinity of the nests with fledglings of Barred Warbler. The next goal of my study was to discover the relationship between the Barred Warbler and the Red-backed Shrike nesting together.
|
|
|
How the red-backed shrike (Lanius collurio) recognizes enemies
NĚMEC, Michal
This study investigates two questions about anti-predator behaviour of the red-backed shrike. 1) Is the red-backed shrike able to assess the differing dangers represented by various types or species of predators? 2) How does the red-backed shrike recognize the predator? We found, that the red-backed shrike (Lanius collurio) adjusts its anti-predator behaviour by assessing the potential threat to themselves from different predator species and by assessing the chance of a successful attack. Further, we found that the presence of general raptor salient features is absolutely necessary for proper categorisation of the intruder as a predator, whereas the natural species-specific colouration in itself is an insufficient cue.
|
|
|
The influence of the presence of invasive map turtle on the activity of brown frog tadpoles.
KLAPKA, Vladimír
The thesis focuses on the factors that influence locomotor activity of tadpoles. An important factor is the risk of predation. The presence of a predator or its metabolites induced in many species of tadpoles reduced locomotor activity. Another factor that affects the locomotor activity of the tadpoles is the presence in the group of conspecific individuals. A laboratory experiment was created to evaluate the influence of these two factors on the locomotor activity of Rana temporaria tadpoles in the presence of metabolites of invasive turtle Trachemys scripta elegans. In the experiment, the rate of tadpole's locomotor activity was expressed by the length of tadpole's trajectory which was measured by camera and evaluated by EthoVision software. The measurement results show that tadpoles in the presence of metabolites of turtle showed antipredator behavior, reduce their locomotor activity. The presence of the tadpole in group with 5 other conspecific individuals did not affect the locomotor activity. The group could only communicate with chemical signals. Conversely interaction was found between the effect of the presence of metabolites of predator and influence group. Tadpoles in the group in the presence of a predator showed greater locomotor activity than single tadpoles in the presence of these metabolites.
|
|
|
Manipulation hypothesis: critical review of published works on parasitic invertebrates
TRÁVNÍČKOVÁ, Jana
The manipulation hypothesis has attracted many researchers, and at present it seems to be documented fora wide range of parasites. However, in the last thirty years, numerous parasites have been revealed that, in fact, cannot manipulated with their host morphology, behaviour, and/or habitat preference, unlike conclusions of the previous studies. The major purpose of this study is to test critically the plausibility of the hypothesis about parasitic manipulation, based on metaanalysis of 55 papers concerning four helminth taxa, namely, Acanthocephala, Cestoda, Trematoda, and Nematomorpha.
|
|
|
How important are cannibalism and intraguild predation for aquatic insect communities?
PEROUTKA, Miroslav
Cannibalism and intraguild predation in the communities of aquatic insects are reviewed. Special attention is paid to the relationship of predator and prey size and to the impact of cannibalism and intraguild predation on population dynamics and individual life histories. Detection of prey and predator and antipredator strategies are also reviewed. The review is complemented by laboratory experiments on selected species of dragonflies.
|
|
| |
|
|
Antipredation behaviour of the Red-Backed Shrike (\kur{Lanius collurio}) against corvids
NĚMEC, Michal
In previous studies with stuffed dummies, we found interesting difference in nest defence of Red-Backed Shrike (Lanius collurio) against two similar nest predators: Jay (Garrulus glandarius) and Magpie (Pica pica). Jay was attacked very intensively, whereas Magpie almost wasn´t hited and Shrikes seemed to keep in cover. Here, I describe the antipredation behavior of the Red Backed Shrike against another stuffed corvids presented closely to Shrikes nests: Jay (Garrulus glandarius), Common Nutcracker (Nucifraga caryocatactes), Rook (Corvus frugilegus), Crow (Corvus corone) and Raven (Corvus corax). I found Jay and Nutcracker to be attacked by Shrikes very strongly, whereas Rook, Crow and Raven were attacked rarely (Shrikes only flied around them or sit at a distance, watching the dummy, sometimes accompanied with alarm-calls). Shrikes response is affected mainly by kind of predator, by age of youngs and by quality of concealment of nest. More - www.mn.ic.cz
|
guest ::
