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Manipulation of physical environment and cognition in primates: Ontogenetic development
Kolářová, Anna ; Nekovářová, Tereza (advisor) ; Hradec, Michal (referee)
Cognition is a crucial factor for primates as it allows properly perceive and respond to the surrounding environment. This thesis is devoted to cognitive phenomena, which are often associated with understanding the physical environment and object manipulation. Much attention is focused on causal reasoning, object permanence and tool using. Particular emphasis is placed on the ontogenesis of these cognitive abilities. One of the main questions is how development differs between humans and non-human primates. Despite the fact that non- human primates, just like humans, have a very complex knowledge of the laws of the physical environment, causal reasoning and object permanence develops in a very similar way for these related species, but far from the same way. A large disparity is observed mainly in the area of the pace of development. Tool use in humans and non-human primates is strongly influenced by social learning and traditions. Key words: primates, physical environment, cognitive abilities, causal reasoning, object permanence, object manipulation, tool using, ontogeny
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The ontogeny of vocalisation in gibbons Nomascus
Hradec, Michal ; Bartoš, Luděk (advisor) ; Pavel, Pavel (referee)
Knowledge of the ontogeny and development of vocalization in primates play a crucial role in understanding the evolution of the human language. Unlike the great apes, gibbons produce a remarkable vocal performance, which includes complex species- and sex-specific patterns. Many studies in the past focused on research of the acoustic pattern in adult individuals. Yet, it remains unclear how the males develop their sex-specific pattern of vocalization.
This dissertation focuses on two specific periods in the ontogenetic development of acoustic structures in male Northern-white cheeked gibbons (Nomascus leucogenys) and Southern-yellow cheeked gibbons (Nomascus gabriellae). The results showed that the first time immature males (juvenile and adolescent) produced female acoustically structured great calls in duets with their mothers. How the great call was structured in immature males differed from the great call of their mothers; the difference being in spectro-temporal parameters from. The most significant difference between juvenile and adolescent males in the production of female vocalization was the presence of a twitter vocalization towards the end of their call. The results show that the twitter was a regular part of female vocalization in juvenile males around four years of age, while younger males produced this vocalization exceptionally. The second period in the ontogeny of vocalization in immature males (adolescent) was characterized by the fact that after five years of age, the development of the male acoustic structure begins. During this period, we did not observe the production of the female vocalization great call in any of the monitored Nomascus gibbon individuals. Results show that the ontogenetic process of the male song in Northern-white cheeked gibbons (N. leucogenys) did not develop in the same sequence as in adults which produced different notes and phrases. The immature male (adolescent male) first time developed the multi-modulation phrase (coda) and the staccato note (syllables) simultaneously at the beginning of this study, but, it was observed that they started producing the boom note four months later. Conversely, the development of the acoustic structure in male Southern-yellow cheeked gibbons (N. gabriellae) was characterized only by the development of a multi-modulation phrase. Development of the staccato syllables was not noted in this species during the study. The results support the interpretation that the development of the male acoustic structure closely corresponds to the growth of the vocal tract and physiological changes associated with reaching sexual maturity.
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The effect of Toxoplasma gondii on the intermediate host
Vosátka, Martin ; Chaloupková, Helena (advisor) ; Hradec, Michal (referee)
Toxoplasma gondii is a protozoan parasite, which has a wide spectrum of warm-blooded hosts, human included. It has worldwide occurrence. The most important role for it has a feline, which serves like a definitive host and allows it to proliferate. The aim of this bachelor thesis was to sum up all identified information so far about the possibilities of relationship between protozoan parasite and its intermediate hosts mainly in area of behavior. Laboratory mouse, the most examined animal associated with behavioral changes, was chosen as an intermediate host. This thesis was also aimed on affecting of human behavior by Toxoplasma gondii in general and about problems connected with it, for example connection with mental diseases and higher risk of traffic accidents. Manipulation of mice by Toxoplasma leads to change in basic instincts necessary for survival. It is especially about attraction to feline odour, when the degree of attraction depends on the dose of stimulus. Area of learning and memory was examined at mice model as well. Worsen ability of learning and memory was demonstrated in most cases (Flegr et al., 2014). Also relationship between number of cysts in the brain and worse results were observed (Vyas et al., 2007). Another important area was human reaction time. Infected individuals had slower reactions, which indicates worsen long-term concentration (Havlíček et al., 2001). Worsen concentration plays an important role and it is connected with a chance of susceptibility to accidents and riskiness for drivers. The individuals with latent Toxoplasma had 2,65 times higher chance for traffic accident (Flegr et al., 2002). T. gondii plays an important role in mental diseases, especially in link with schizophrenia. Effective medication of schizophrenia can inhibit T. gondii (Yolken et al., 2009). Schizophrenia often results in suicide attempt. That is why possible link between suicide attempts and presence of the parasite was researched. The study shows connection between antibody levels of T. gondii and suicide attempts, but just in a subgroup of patients younger than 38 years. It is probably because of risk of suicide attempts in schizophrenia appears in earlier phase of the disease (Okusaga et al., 2011).
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Prenatal stress in the farm animals
Tylová, Barbora ; Chaloupková, Helena (advisor) ; Hradec, Michal (referee)
This bachelor thesis presents summary information about prenatal stress in farm animals, more precisely in ruminants. The thesis is based on scientific papers and literature. Prenatal stress is divided according to stressors that can affect animals in agriculture like transport, manipulation, diet restriction, isolation, social instability and heat stress. The work describes principles of how the stress is transmitted from mother to the fetus, how the stress affects them and to what extent. Scientific articles confirmed the effect of prenatal stress on placental development (Baxter et al., 2016 ; McCrabb and Bortolussi, 1997) birth weight (Roussel et al., 2004; Duuvaux Ponter et al., 2003) nervous system (Weinstock, 2001; Baxter et al. 2016) and the offspring behavior (Roussel Huchette et al., 2008; Laporte Broux et al., 2012; Coulon et al., 2011). As pregnant females were in most of the cases exposed to a mild stress (compared to previous experiments on laboratory animals) the effect on offspring had a little impact on the body that proved to be beneficial. Some studies showed that abnormalities that were measured after birth were not proven at later age.
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The relationship between the sow and piglets - how piglets recognize their mother's vocalizations
Zátková, Marcela ; Chaloupková, Helena (advisor) ; Hradec, Michal (referee)
The ability to recognize mothers voice is important for offspring in many animal species. This thesis reviews the knowledge on maternal behaviour in domestic pigs and focuses on its important prerequisite which is the recognition between mother and her offspring. Domestic pig (Sus scrofa domestica) is chosen as a very good model species. Maternal behaviour of pigs did not change much due to domestication or inetnsive farming. Maternal behaviour including nursing behaviour should prevent monpolization of resources by stronger piglets. Therefore, maternal behaviour has interesting aspects: long udder massage, attraction of piglets with vocalization and announcment of milk ejection with short period of milk ejection. Maternal behaviour in pigs involves a complex of many interesting phenomena like: synchronization of nursings, non-nutritive nursings, potential for allo-suckling, parent-offspring conflict, specific initiation and termination of nursing and rich olfactoric, acoustic, and tactile signalling. Pig belongs to social animals in which communication needs to be complex, especially acoustic communication. Naturally, recognition of individuals is crucial in groups and this is true for recognition between mother and offspring. The acoustic recognition can be studied by three appraches. 1) Observing of natural behaviour, 2) Playback experiments (habituation, preference and comparison) and 3) Analysis of voice and searching for individual traits in voice. It is expected, that piglets should recognize mother as soon as possible. Sow should recognize piglets after rejoining her group. Results of the studies reviewed in this thesis seem to confirm these assumption. Piglets recognize their mother 36h after parturition by voice. Sows can recognize the smell of own piglets soon after parturition but not by voice. Identification based on voice seems to appear later at about 10 days after parturition, but it is not very strong. Other studies identified potential cues to identity in calls of sows as well as in calls of piglets.
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