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Effect of carrion size on the succesion of the nephilous insect society
Mikátová, Šárka ; Šípek, Petr (advisor) ; Jakubec, Pavel (referee)
The aim of this work was to assess the effect of carrion size on insect communities succession based on previously published studies. Assessement of various factors on carrion is important in forensic analysis and to determine the PMI (post morte interval). The most abundant and investigate groups of carrion insects are Diptera and Coleoptera. Model organism in most cases is a pig (Sus scrofa L). Decomposition of small carrions varies from medium and large size carrion, which causes different succession of insects. Relevant judging of differences between studies is not possible because of many factors which affect carrion decomposition. Key words: necrobiont insects, carrion, body size, Diptera, Coleoptera
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Sexual selection in Scarab beetles with empahsis to the subfamily Scarabaeinae (Coleoptera: Scarabaeoidea)
Kněnická, Kateřina ; Šípek, Petr (advisor) ; Král, David (referee)
Sexual selection is a very important phenomenon in nature. In this work, I focused on the mechanisms of sexual selection in scarab beetles, with a strong emphasis on group Scarabaeinae (Coleoptera: Scarabaeoidea: Scarabaeinae). The first part is devoted to selection and its classification the sexual reproduction and related effects. I tried to describe the list of forms of sexual dimorphism in individual families and groups of Scarabaeoidea and describe life strategies subfamilies Scarabaeinae. Finally I list the factors influencing the individual the attractiveness in the relation to mating success. Powered by TCPDF (www.tcpdf.org)
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Habitat shifts to aquatic environment and back to dry land in the evolution of Coleoptera
Sýkora, Vít ; Fikáček, Martin (advisor) ; Král, David (referee)
The order Coleoptera (beetles) includes both terrestrial and aquatic species. The whole order as well as for all suborders (Archostemata, Myxophaga, Adephaga and Polyphaga) in ancetrally terrestrial. Habitat shifts occured in all suborders except Archostemata. A single shift to aquatic environment is probable in Myxophaga and Adephaga, multiple independent shifts from aquatic to terrestrial environments took place in Polyphaga. Multiple secondary habitat transitions back to terrestrial life style occured in Adephaga, Myxophaga and Polyphaga. However, phylogenetic relationships and/or detailed habitat requirements of adults and larvae are still unknown for many groups. That is why a reliable reconstruction of the evolution of habitat transitions between aquatic and terrestrial environment is still impossible in many cases. Key words: Coleoptera, habitat shifts, aquatic environment, terrestrial environment, evolution, phylogeny, biodiversity, morphology, adaptation
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Comparison of water beetles fauna between forefield and reclamation of the landscape affected by mining
Vostalová, Adéla ; Vrabec, Vladimír (advisor) ; Josef, Josef (referee)
The issue of redress anthropogenic interference with the landscape is one of the discussed topics today not only in professional groups but also among the public, because mineral mining takes place in many places in the Czech Republic. More and more are beginning to promote nearnatural methods of renewal at the expense of recently prevalent technical reclamation. Except for question, how the exhausted places reuse or renew also researches, how the whole process has an impact on the local fauna and flora.
The aim of this thesis was a qualitative comparison of water beetles among the forefield Bílina Mine and reclamation dumps Radovesice and Pokrok in North Bohemia province. It was evaluated 16 reservoirs in forefield and 15 reservois of dumps. A total of 36 taxa were found from which 19 were determined only at the species level. The most of taxa were located at post R9 in the forefield, at 4 locations there were none of them. The most abundant was genus Haliplus.
The collection took place using standard hydrobiological sampling by sieve. The material was preserved in alcohol, then separated, prepared and finally determined. The obtained data were evaluated and compared using the Jaccards index of similarity.
It was tested hypothesis: Due to the good dispersion ability of water beetle is representation of species in the forefield the same as constitution of species in the newly ponds at reclamations. Calculation Jaccard index between locations of forefield and dump reached the highest value of similarity 66,7 %, but over of the value 50% moved only in 7 cases out of 465 possible combinations, thereby hypothesis was disproved.
Found species were also evaluated from point of view conservation status according to the Red list of threatened species in the Czech Republic. This way was detected only one species, Laccophilus poecilus, falling into the category VU vulnerable. The determination must be examined.
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Wing reduction in cockroaches (Blattaria)
Kotyk, Michael ; Kotyková Varadínová, Zuzana (advisor) ; Nedvěd, Oldřich (referee)
My bachelor thesis deals with the wing reduction in cockroaches and the causes of its appearance. Order Blattaria is the insect order with the third highest occurrence of apterous and brachypterous species. Yet still only a minimum of publications were performed to cover this topic. Therefore, I analyse in several chapters both the types of wing reduction as well as generally accepted theories explaining the reasons of its evolution in insects. Then I discuss their relevance in the case of order Blattaria. Namely, ecological theories, regarding interactions of insect and its habitat, and physiological theories, describing life history trade- offs and constrains related to wings. I present examples of species to every theory which are probably concerned. There are also examples of species which maintain the macropterous state, although no longer capable of flight and theories that explain the retention of macroptery. As a part of the thesis I have also included a phylogenetic tree of cockroaches with marked wing condition for each sex, which outlines evolutionary trends of individual groups within the order. Keywords: Blattaria, reduction, macroptery, brachyptery, aptery, habitat, life history trade-offs
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Phylogeography and conservation genetics of endangered saproxylic beetles in Europe
DRAG, Lukáš
This thesis introduces the use of molecular methods for the conservation of several species of endangered saproxylic beetles in Europe. It focuses on the questions related to the DNA preservation and microsatellites development, as well as the evolutionary history and conservation of threatened species. Using the combination of mitochondrial and nuclear markers, the genetic diversity and reintroduction history of Cerambyx cerdo was assessed and the phylogeography of Rosalia alpina from the whole range of its distribution was studied. This information is valuable for designing more efficient conservation strategies.
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Ecological and evolution strategies of necrophagous beetles (Coleoptera)
Jakubec, Pavel ; Růžička, Jan (advisor) ; Petr, Petr (referee)
Necrophagous beetles (Coleoptera) are very interesting and diverse ecological group of species with an immense impact on a natural nutrient cycle. Their main food source and breeding ground are carrions of vertebrates, human remains included. This relationship is often used in various ways by forensic entomology, but its potential was not jet fully reached, because our knowledge of biology and ecology of these beetles is very much incomplete. In this thesis I would like to explore geographic distribution, ecological requirements and developmental biology of several Central European necrophagous beetles as an outcome of their ecological and evolution strategies. For that I raised three broad research questions. Which factors are determining the local abundance of carrion beetles (Coleoptera: Silphidae)? How the current geographical distribution of open-landscape carrion beetles looks like in the Czech Republic? How the temperature affects the development of Sciodrepoides watsoni (Spence, 1813)? We found out that soil type can have significant effect on abundance of carrion beetles. They showed preference for chernozem -- Nicrophorus antennatus (Reitter), N. germanicus (Linnaeus), N. interruptus (Stephens), N. sepultor (Charpentier), Silpha obscura obscura (Herbst), T. sinuatus (Fabricius) or for fluvisol as did N. humator (Gleditsch). These findings support our hypothesis that soil type could be an important factor determining the occurrence of necrophagous European carrion beetles. To collect novel data of the current geographical distribution of carrion beetles we used 420 baited pitfall traps at 84 localities, and we collected 71 234 specimens of 15 silphid species. Among them, three endangered carrion beetle species listed on the Czech Red List of Invertebrates, were found. Two are vulnerable thermophilic species of open landscapes, Nicrophorus antennatus (Reitter, 1884) (collected around Louny and Židlochovice) and Nicrophorus germanicus (Linnaeus, 1758) (Louny, Zábřeh and Židlochovice). The third is the near threatened species, Nicrophorus sepultor Charpentier, 1825 (collected around Louny, Kutná Hora, Zábřeh and Židlochovice), which also prefers open landscapes. We studied development of common Holarctic beetle Sciodrepoides watsoni under five constant temperature regimes in laboratory (15, 18, 21, 25 and 28°C). Parameters of thermal summation models and their standard errors were calculated for each developmental stage (egg, three larval instars and pupae). We also find a new character for larval instar determination (head width) and proposed novel approach for future studies of size-based characters in instar determination.
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