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Morphological variation of Cameroonian sunbirds
Bovšková, Denisa ; Hořák, David (advisor) ; Chmelová, Eliška (referee)
5 Abstract Morphological traits give information about the adaptations of the studied species, the resources, which it uses, and they can generally tell us about the use of ecological space. Intraspecific morphological variability reflects various adaptations of local populations thus variability reflect different way of life. The subject of this thesis is an ecologically interesting group of specialized tropical songbirds - Sunbirds (Nectarinidae). The taxon exhibits number of adaptations to specific food collecting a combination of nectarivory and insect hunting. I focused here on the intraspecific variability of three species (Cyanomitra oritis, Cinnyris reichenowi and C. bouwieri) living in different habitats in Cameroon. The aim of this work was to find out in what morphological characters are this species sexually dimorphic. Furthermore, if their populations living in remote locations differ? Finally, if all studied species show similar trend of intraspecific variability of the traits, which could have common ecological causes. The following traits were measured: wing and tail feather length, beak dimensions, total body weight and other characters. The analysis is based on field data collected between 2003 and 2015 and museum collections. Overall, we collect information about ca. 1200 individuals for...
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Distribution of photoreceptor types in retina of fishes from extreme environments
Remišová, Kateřina ; Musilová, Zuzana (advisor) ; Němec, Pavel (referee)
Cichlid visual system is highly adaptive to the environment. Fish visual abilities are deter- mined by composition of opsin-based photosensitive pigments located in photoreceptor cells (rods and cones) as well as their distribution. In this thesis, four species of Lake Barombi Mbo cichlids were targeted: Stomatepia mariae, Konia eisentrauti, Konia dikume and Myaka myaka. Shallow-water cichlids K. eisentrauti and S. mariae express these types of cone opsin genes: LWS, RH2A (RH2Aβ more than RH2Aα), SWS2A and SWS2B. Contra- rily, both seasonally deep-water M. myaka and deep-water K. dikume lack expression of SWS2B and LWS in their retinae, but they express SWS2A and RH2Aα more than RH2Aβ, which corresponds to modified light conditions in deep water - a dimmer habitat lacking marginal parts of the spectrum (i.e., ultraviolet and red wavelengths). The photoreceptor distribution of selected species was investigated by means of fluorescent in situ hybridi- zation (FISH) in order to understand the performance and evolution of their visual per- ception with emphasis on the effect of depth. Distinctively, cichlid cones are arranged in a retinal mosaic consisting of short-wavelength sensitive single cones, each surrounded by four long-wavelength sensitive double cones. In this thesis, the same arrangement is...
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Coevolution of avian ectoparasites in the tropics
Gajdošová, Magdalena ; Munclinger, Pavel (advisor) ; Votýpka, Jan (referee)
Host-parasite associations are born by cospeciations or by host switches. Feather lice have traditionally been used as model parasites for studying these events and underlying ecological factors. By now tens of analyses have addressed comparisons of host and parasite phylogenies to study cospeciations and host switches in lice, however, these analyses are strongly biased towards the temperate zone. Tropical environment could provide new insight into the origin of host-parasite interactions, because it is ecologically unique. This work aims to supplement the knowledge of host-parasite associations in lice using coevolution analyses of two feather lice genera and their passerine hosts in tropical rainforest in Cameroon. It shows that lice in the tropics cospeciate rarely. To assess whether host switches are non-random and occur preferentially between hosts with specific traits, this work also analyses relations between parasite genetic distances and hosts' trait similarities. No effect of host morphology and spatial distribution was found. However, genetic distances of the lice strongly correlate with genetic distances of their hosts.
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Morphological variation of Cameroonian sunbirds
Bovšková, Denisa ; Hořák, David (advisor) ; Chmelová, Eliška (referee)
5 Abstract Morphological traits give information about the adaptations of the studied species, the resources, which it uses, and they can generally tell us about the use of ecological space. Intraspecific morphological variability reflects various adaptations of local populations thus variability reflect different way of life. The subject of this thesis is an ecologically interesting group of specialized tropical songbirds - Sunbirds (Nectarinidae). The taxon exhibits number of adaptations to specific food collecting a combination of nectarivory and insect hunting. I focused here on the intraspecific variability of three species (Cyanomitra oritis, Cinnyris reichenowi and C. bouwieri) living in different habitats in Cameroon. The aim of this work was to find out in what morphological characters are this species sexually dimorphic. Furthermore, if their populations living in remote locations differ? Finally, if all studied species show similar trend of intraspecific variability of the traits, which could have common ecological causes. The following traits were measured: wing and tail feather length, beak dimensions, total body weight and other characters. The analysis is based on field data collected between 2003 and 2015 and museum collections. Overall, we collect information about ca. 1200 individuals for...
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A Business Plan for Exporting Goods from the Czech Republic to Cameroon
Burianová, Šárka ; Chylíková, Hana (advisor) ; Elblová, Veronika (referee)
The main aim of my work is writing a business plan for the export of goods from the Czech Republic to Cameroon. The business plan is designed for the needs of entrepreneur who would like to get engaged in the export in future. The first phase of the thesis consists of theoretical background that will enable readers to get familiar with basic concepts of business, international trade, the structure as well as content of a business plan. Furthermore, they are given basic information about Cameroon, on business conditions in the country and on international trade. The practical part is devoted entirely to developing the business plan for the export of goods from the Czech Republic to Cameroon. First is specifically characterized by the business opportunity and competitive advantage businesses. The reader is acquainted with the selection of the type of imported goods and with resulting SWOT and PEST analyzes. Based on the hierarchical segmentation is defined customer target group and analyzed the competitive environment. Great attention is then paid to the marketing and sales strategy and quantify the costs necessary for starting a business and making its first export options, including their financing. Finally we are capitulating prerequisites for project success and business areas where it can be seen potential risks.
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Phylogeography of mountain butterfly ??Bicyclus anisops in West Africa
PETRŮ, Vojtěch
The Gulf of Guinea Highlands is a unique mountane range of volcanic origin, situated on the African mainland in the borther of Nigeria and Cameroon, and the Gulf of Guinea islands of Bioko, S?o Tomé and Príncipe. This area is highly unique as the only large mountains in central and western Africa. The high degree of isolation of these mountains generated high degree of endemism of many groups of organisms; the whole region is thus one of the world biodiversity hotspots (known as the West African Forests). Despite its tremnedous conservation importance, this mountain range is under strong anthropogenic influence, as one of the most densely populated areas in tropical Africa. Despite all these factors, the conservation efforts in West Africa focused mainly on lowland areas of rain forests, whilst only few conservation effort is focused to the mountain habitats. As the other result, the lack of comprehensive biogeographic and phytogeographical studies of mountain flora and fauna is obvious. In this work, I have summarized the results of all crucial studies of the biogeography of the Gulf of Guinea Highlands. I also obtained sequences of three mitochondrial genes (COI, COII, and ND1) of an endemic montane butterfly Bicyclus anisops. Variability in the studied genes was relatively low. Phylogenetic analyses separated haplotypes into 7 well-established groups (1st Mt. Cameroon, 2nd Nkogam I, 3rd Nkogam II, 4th Bakossi-Kupe-Manengouba-Bani, 5th Mbam, 7th Hosséré Enla Fabo 6th all others localities (tj. Bamenda-Banso Mts., Acha Tugi, Mbam, Ngel Nyaki, Gotel Mts.)) but did not significantly resolved relationships among them. Based on the hyplotype diversity of B. anisops as an umbrella species, Mt. Cameroon, Nkogam, Mbam Massif, Mbiame, Hosséré Enla Fabo, Mt. Manengouba, Mt. Kupe and Mt. Oku are considered as localities of the highest conservation importance.
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