Molekularna ekologija velikog vijuna (Cobitis elongata, Heckel & Kner, 1858)

master's thesis

• Title (english): Molecular ecology of the balkan loach (Cobitis elongata, Heckel & Kner, 1858)
• Author: Petra Nemec
• Mentor: Ivana Buj (mentor)
• Committee member: Ivana Buj (predsjednik povjerenstva)
• Committee member: Ivan Radosavljević (član povjerenstva)
• Committee member: Ana Galov (član povjerenstva)
• Committee member: Davor Zanella (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2019-02-21, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology

Abstract

Veliki vijun (Cobitis elongata Heckel & Kner, 1858) je slatkovodna riba iz porodice Cobitidae koja je endem dunavskog slijeva te je zaštita njezinih populacija nuţna. Filogenetski odnosi, eventualna povezanost populacija migracijama, kao i evolucija ove vrste nisu dovoljno istraţeni, a podataka koji bi obuhvaćali cijeli areal rasprostranjenosti nema. Cilj ovog istraţivanja bio je: ustanoviti filogenetske i filogeografske odnose populacija velikog vijuna radi utvrĊivanja intraspecijske strukturiranosti, utvrditi gensku raznolikost pojedinih populacija i ĉitave vrste, procijeniti efektivnu veliĉinu pojedinih populacija te cjelokupne vrste, rasvijetliti evolucijsku povijest te odrediti pribliţno razdoblje nastanka velikog vijuna kao i vremena divergencije pojedinih populacija. Da bi se utvrdila intraspecijska struktura velikog vijuna, provedena je filogenetska rekonstrukcija na temelju sekvenci mitohondrijskog gena za citokrom b pomoću metoda najveće parsimonije, Bayesove metode te metode susjednog sparivanja. Pomoću raĉunalnog programa DnaSP odreĊene su mjere genskog polimorfizma, a pomoću programa MIGRATE stope migracija izmeĊu populacija. Vremena divergencije odreĊena su korištenjem programa Beast. Rezultati dobiveni provoĊenjem navedenih metoda pokazali su da je vrsta duboko strukturirana te da postoje ĉetiri grupe haplotipova. UtvrĊena je niska intraspecijska i intrapopulacijska raznolikost te genska izoliranost populacija i mali protok gena. Male efektivne veliĉine populacija te slaba povezanost populacija odraz su ekologije ove vrste.

Abstract (english)

Balkan loach (Cobitis elongata Heckel & Kner, 1858) is freshwater fish from the Cobitidae family which is endem of Danube watershed and protection of their populations is necessary. Phylogenetic relationship, the possible connection between population through migrations, as well as the evolution of this species are not sufficiently researched and there is not enough data about whole areal of prevalence. The aim of this study was to: establish the phylogenetic and phylogeographic relations of the balkan loach to identify intraspecific structure, to determine genetic diversity of certain populations and the whole species, estimate the effective size of the individual populations and the whole species, clarify the evolution history and determine the approximate period of occurrence of this species as well as the divergence of individual populations. In order to determine intraspecific structure of balkan loach, a phyolgenetic reconstruction was conducted based on the mitochondrial gene sequence for cytochrome b using the several methods: maximum parsimony, Bayesian method and median joining. Using the DnaSP computer program, the measures of the genetic polymorphism are determined and with MIGRATE migration rate among the population. Divergence times are determined using Beast software. The results obtained by these methods have shown that the species is deeply structured and that there are four groups of haplotypes. Also, low intraspecific and intrapopulation diversity was determined along with genetic isolation of population and low flow of genes. Small effective population sizes and poor population connectivity are the reflection of ecology of this species.

• Keywords: veliki vijun; filogenija; citokrom b; genska raznolikost; protok gena
• Keywords (english): balkan loach; phylogeny; cytochrome b; genetic diversity; gene flow
• Language: croatian
• URN:NBN: urn:nbn:hr:217:053268
• Study programme: Title: Ecology; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra ekologije i zaštite prirode (magistar/magistra ekologije i zaštite prirode)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access; Embargo expiration date: 2021-02-21
• Created on: 2019-03-26 10:10:42