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To explore local adaptation in wild populations at a fine spatial scale we characterized the genetic variability of eight closely located populations of Drosophila subobscura and its associations with microhabitat environmental conditions. Three different genetic markers were assessed: chromosomal inversions, a SNP of mitochondrial ND5 gene and nuclear microsatellites. Population genetic analyses of chromosomal variability revealed significant genetic differentiation between these populations. Gene arrangement frequencies on the E chromosome contributed most to these differences. We also investigated role of mitonuclear epistasis in mitochondrial genome differentiation and revealed weak linkage disequilibrium (LD) exclusively between O-3+(4) inversion arrangement and mitochondrial DNA haplotype I in two populations. In addition, the trend in the LD between O-ST chromosomal arrangement and haplotype II was general in the total sample. Microsatellite analysis revealed an absence of stochastic processes, like census reduction, upon population differentiation. Only a small amount of the genetic variation is related to geographic distance, while most (97%) is attributable to other factors and in some degree to microhabitat variables (temperature, humidity). The analysis of these factors revealed they effect inversion arrangement frequencies, especially E1+2+9, E-ST and O-ST. Even though this model organism is known for its high mobility and mostly large effective population size, the results presented here reveal that local adaptations can occur even at a small spatial scale. We propose that locally adapted alleles within chromosomal inversions, as well as joint selective pressures acting on mitochondria! and nuclear genomes, are responsible for the observed adaptation to microhabitat conditions.

To explore local adaptation in wild populations at a fine spatial scale we characterized the genetic variability of eight closely located populations of Drosophila subobscura and its associations with microhabitat environmental conditions. Three different genetic markers were assessed: chromosomal inversions, a SNP of mitochondrial ND5 gene and nuclear microsatellites. Population genetic analyses of chromosomal variability revealed significant genetic differentiation between these populations. Gene arrangement frequencies on the E chromosome contributed most to these differences. We also investigated role of mitonuclear epistasis in mitochondrial genome differentiation and revealed weak linkage disequilibrium (LD) exclusively between O-3+(4) inversion arrangement and mitochondrial DNA haplotype I in two populations. In addition, the trend in the LD between O-ST chromosomal arrangement and haplotype II was general in the total sample. Microsatellite analysis revealed an absence of stochastic processes, like census reduction, upon population differentiation. Only a small amount of the genetic variation is related to geographic distance, while most (97%) is attributable to other factors and in some degree to microhabitat variables (temperature, humidity). The analysis of these factors revealed they effect inversion arrangement frequencies, especially E1+2+9, E-ST and O-ST. Even though this model organism is known for its high mobility and mostly large effective population size, the results presented here reveal that local adaptations can occur even at a small spatial scale. We propose that locally adapted alleles within chromosomal inversions, as well as joint selective pressures acting on mitochondria! and nuclear genomes, are responsible for the observed adaptation to microhabitat conditions.

To explore local adaptation in wild populations at a fine spatial scale we characterized the genetic variability of eight closely located populations of Drosophila subobscura and its associations with microhabitat environmental conditions. Three different genetic markers were assessed: chromosomal inversions, a SNP of mitochondrial ND5 gene and nuclear microsatellites. Population genetic analyses of chromosomal variability revealed significant genetic differentiation between these populations. Gene arrangement frequencies on the E chromosome contributed most to these differences. We also investigated role of mitonuclear epistasis in mitochondrial genome differentiation and revealed weak linkage disequilibrium (LD) exclusively between O-3+(4) inversion arrangement and mitochondrial DNA haplotype I in two populations. In addition, the trend in the LD between O-ST chromosomal arrangement and haplotype II was general in the total sample. Microsatellite analysis revealed an absence of stochastic processes, like census reduction, upon population differentiation. Only a small amount of the genetic variation is related to geographic distance, while most (97%) is attributable to other factors and in some degree to microhabitat variables (temperature, humidity). The analysis of these factors revealed they effect inversion arrangement frequencies, especially E1+2+9, E-ST and O-ST. Even though this model organism is known for its high mobility and mostly large effective population size, the results presented here reveal that local adaptations can occur even at a small spatial scale. We propose that locally adapted alleles within chromosomal inversions, as well as joint selective pressures acting on mitochondria! and nuclear genomes, are responsible for the observed adaptation to microhabitat conditions.

To explore local adaptation in wild populations at a fine spatial scale we characterized the genetic variability of eight closely located populations of Drosophila subobscura and its associations with microhabitat environmental conditions. Three different genetic markers were assessed: chromosomal inversions, a SNP of mitochondrial ND5 gene and nuclear microsatellites. Population genetic analyses of chromosomal variability revealed significant genetic differentiation between these populations. Gene arrangement frequencies on the E chromosome contributed most to these differences. We also investigated role of mitonuclear epistasis in mitochondrial genome differentiation and revealed weak linkage disequilibrium (LD) exclusively between O-3+(4) inversion arrangement and mitochondrial DNA haplotype I in two populations. In addition, the trend in the LD between O-ST chromosomal arrangement and haplotype II was general in the total sample. Microsatellite analysis revealed an absence of stochastic processes, like census reduction, upon population differentiation. Only a small amount of the genetic variation is related to geographic distance, while most (97%) is attributable to other factors and in some degree to microhabitat variables (temperature, humidity). The analysis of these factors revealed they effect inversion arrangement frequencies, especially E1+2+9, E-ST and O-ST. Even though this model organism is known for its high mobility and mostly large effective population size, the results presented here reveal that local adaptations can occur even at a small spatial scale. We propose that locally adapted alleles within chromosomal inversions, as well as joint selective pressures acting on mitochondria! and nuclear genomes, are responsible for the observed adaptation to microhabitat conditions.

To explore local adaptation in wild populations at a fine spatial scale we characterized the genetic variability of eight closely located populations of Drosophila subobscura and its associations with microhabitat environmental conditions. Three different genetic markers were assessed: chromosomal inversions, a SNP of mitochondrial ND5 gene and nuclear microsatellites. Population genetic analyses of chromosomal variability revealed significant genetic differentiation between these populations. Gene arrangement frequencies on the E chromosome contributed most to these differences. We also investigated role of mitonuclear epistasis in mitochondrial genome differentiation and revealed weak linkage disequilibrium (LD) exclusively between O-3+(4) inversion arrangement and mitochondrial DNA haplotype I in two populations. In addition, the trend in the LD between O-ST chromosomal arrangement and haplotype II was general in the total sample. Microsatellite analysis revealed an absence of stochastic processes, like census reduction, upon population differentiation. Only a small amount of the genetic variation is related to geographic distance, while most (97%) is attributable to other factors and in some degree to microhabitat variables (temperature, humidity). The analysis of these factors revealed they effect inversion arrangement frequencies, especially E1+2+9, E-ST and O-ST. Even though this model organism is known for its high mobility and mostly large effective population size, the results presented here reveal that local adaptations can occur even at a small spatial scale. We propose that locally adapted alleles within chromosomal inversions, as well as joint selective pressures acting on mitochondria! and nuclear genomes, are responsible for the observed adaptation to microhabitat conditions.

In insects, cuticular hydrocarbon (CHC) profile is involved in many important biological functions and may vary in different conditions. Among fruit fly species, Drosophila subobscura is one of the most frequently used in genetic, ecological and evolutionary research, because of its rich chromosomal polymorphism, specific behavioral repertoires and habitat preferences. In this work, we identified and quantified cuticular chemoprofile of D. subobscura. Using gas chromatography (GC) and gas chromatography coupled with mass spectrometry (GC-MS), 25 chemical compounds were found in males and 23 compounds were found in females. Further, ANOVA confirmed significant sexual dimorphism in cuticular chemoprofile amounts. Knowledge of cuticular chemistry could contribute to further research in D. subobscura, starting from behavioral, up to ecological, since this species is recognized as an important model system for the study and monitoring of global climate changes.

Od svog nastanka život na Zemlji se odvijao u prisustvu prirodnih elektromagnetnih polja (EMP) koja su relativno jednostavna i potiču od malobrojnih emitera elektromagnetne energije. Živa bića su se tokom svoje evolucije prilagodila ovom konstantnom sredinskom faktoru, ali su danas pored prirodnih, u sve većoj meri izložena EMP poreklom od izvora koje je stvorio čovek. Intenzitet i frekvencija ovih polja su daleko veći u odnosu na polja prirodnog porekla, a tu spadaju najvećim delom EMP mrežne frekvencije (u okviru dela spektra ekstremno niske frekvencije (ENF) od 50 ili 60 Hz), polja koji potiču od uređaja masovnih (RTV predajnici, 100-500 MHz) i mobilnih komunikacija (800-900 MHz i 1800-2200 MHz). EMP ENF imaju veliki biofizički značaj jer su sveprisutna u životnoj sredini usled prenosa i upotrebe električne energije. Elektromagnetna polja antropogenog porekla predmet su izučavanja različitih bioloških disciplina, ali pre svega sa aspekta zdravlja ljudi. Izlaganje organizama ELM ENF, čak i tokom kraćeg vremenskog perioda, ima za posledicu narušavanje ravnoteže bioloških sistema, kao i poremećaje na različitim nivoima organizacije, ali još uvek ne postoji opšte prihvaćena teorija o mehanizmima dejstva EMP ENF u biološkim sistemima. Pored toga, sredinske promene, usled prisustva EMP ENF, mogu imati uticaj na ekološke i evolucione procese koji utiču na stepen i obim promena u genetičkoj strukturi i evoluciji populacije. Stoga je od suštinskog značaja dublje razumevanje mehanizama koji omogućavaju organizmima da se manje ili više uspešno prilagođavaju sredinskim izazovima, kao i mogućnost da se predvide i prate odgovori populacija na promene u životnoj sredini koja ih okružuje. Tokom poslednje tri decenije izvedene su brojne studije na Drosophila sa ciljem ispitivanja bioloških efekata EMP ENF. Eksperimentalno izlaganje individualnih genotipova Drosophila EMP ENF tokom različitih faza životnog ciklusa, rezultuje različitim odgovorima koji su često oprečni, jer efekat

Jedinke uzorkovane iz dva ekološki različita staništa, i hibridi nastali njihovim ukrštanjem (unutar-linijski, unutar-populacioni i među-populacioni) izlagane su povećanoj koncentraciji olova, čime je omogućeno da se utvrdi razlika u odgovoru jedinki različitog nivoa heterozigotnosti genoma na sredinski stres odnosno, testira hipoteza o heterozigotnoj superiornosti u stresnim uslovima i utvrdi populaciono specifičan odgovor na prisustvo olova. Sinergistički efekat stresa evaluiran je na tri nivoa: populacionom - analizom komponenti adaptivne vrednosti (dužina razvića i preživljavanje od jaja do adulta), morfološkom – analizom varijabilnosti veličine krila i biohemijskom - praćenjem ekspresije proteina toplotnog šoka. Rezultati su pokazali redukciju svih ispitivanih osobina kod inbredovanih jedinki i njihovo povećanje kod jedinki sa višim nivoom heterozigotnosti genoma, potvrđujući hipotezu heterozigotne superiornost koja se intenzivira u stresnim uslovima. Uočen je trend sinergističkog efekta genomskog i sredinskog stresa za komponente adaptivne vrednosti, koji je statistički značajan za veličinu krila, s obzirom da je najintenzivnija redukcija primećena kod inbredovanih jedinki u stresnim uslovima. Nije dobijen populaciono specifičan odgovor u prisustvu olova, ali je utvrđeno da na ishod međupopulacione hibridizacije u stresnim uslovima veliki uticaj ima poreklo ženke i evoluciona istorija njene prirodne populacije. Može se zaključiti da je održavanje genetičke varijabilnosti od velike važnosti za opstanak populacija, i da čak i nizak stepen inbridinga utiče na pad adaptivne vrednosti, naročito u stresnim uslovima sredine., The subject of this dissertation is population genetic analysis of synergistic effect of genomic and environmental stress in model species Drosophila subobscura. Individuals sampled from two ecologically distinct habitats, and their hybrids with different levels of genome heterozygosity (intra-line, intra-population and inter-population hybrids) were exposed to elevated concentrations of lead, aiming to test hypothesis of heterozygote superiority in stressful conditions and detect population specific response to lead pollution. Synergistic effect of stress was evaluated at three levels: population - through analysis of fitness components (development time and egg-to-adult survival), morphological - through analysis of variability in the wings size and biochemical – through the expression of heat shock protein. The results showed a reduction of all investigated traits in inbred individuals and their increase in those with higher levels of genome heterozygosity, confirming the hypothesis of heterozygote superiority which intensifies under stressful conditions. Analysis of fitness components indicates synergistic effect of genomic and environmental stress, and variance in wing size shows statistical significance, since the greatest reduction of all traits was observed in inbred groups. Population specific response to lead pollution was not detected, but significant influence of female origin on the outcome of between-population hybridization under stressful conditions was observed. It can be concluded that the maintenance of genetic variation is important for the survival of populations in changing environments, and even low levels of inbreeding lead to decline in adaptive value, especially in stressful environments.

Growing anthropogenic influence on every aspect of environment arise important issues regarding the ability of populations and species to adapt to variant pressures. Lead is one of the most present contaminants in the environment with detrimental influence on organisms and populations. In combination with genomic stress, lead may act synergistically, leading to reduction in adaptive values. We sampled two Drosophila subobscura populations, from ecologically different habitats and established differences in genetic backgrounds and population histories. In order to establish different levels of genome heterozygosity, series of intra-line, intra-population and between population crosses were made. The progeny was reared on a standard Drosophila medium and a medium with 200 mu g/mL of lead acetate and right wing of approximately 4000 individuals was used for geometric morphometric analysis of wing size. Results showed that lead significantly reduces wing size and that magnitude of this reduction is dependent on genetic background, indicating synergistic effect of genomic and environmental stress. There is also an indication of strong female origin influence on the outcome of hybridization when source of environmental stress is lead. Our results showed that the genetic structure of populations is of great importance for population fitness in anthropogenic induced stressful conditions. Further studies of synergistic effect of genetic and environmental stress are needed, as well as studies of its outcome in natural populations.

Predmet disertacije je populaciono genetička analiza sinergističkog efekta genomskog i sredinskog stresa na model vrsti Drosophila subobscura. Jedinke uzorkovane iz dva ekološki različita staništa, i hibridi nastali njihovim ukrštanjem (unutar-linijski, unutar-populacioni i među-populacioni) izlagane su povećanoj koncentraciji olova, čime je omogućeno da se utvrdi razlika u odgovoru jedinki različitog nivoa heterozigotnosti genoma na sredinski stres odnosno, testira hipoteza o heterozigotnoj superiornosti u stresnim uslovima i utvrdi populaciono specifičan odgovor na prisustvo olova. Sinergistički efekat stresa evaluiran je na tri nivoa: populacionom - analizom komponenti adaptivne vrednosti (dužina razvića i preživljavanje od jaja do adulta), morfološkom – analizom varijabilnosti veličine krila i biohemijskom - praćenjem ekspresije proteina toplotnog šoka. Rezultati su pokazali redukciju svih ispitivanih osobina kod inbredovanih jedinki i njihovo povećanje kod jedinki sa višim nivoom heterozigotnosti genoma, potvrđujući hipotezu heterozigotne superiornost koja se intenzivira u stresnim uslovima. Uočen je trend sinergističkog efekta genomskog i sredinskog stresa za komponente adaptivne vrednosti, koji je statistički značajan za veličinu krila, s obzirom da je najintenzivnija redukcija primećena kod inbredovanih jedinki u stresnim uslovima. Nije dobijen populaciono specifičan odgovor u prisustvu olova, ali je utvrđeno da na ishod međupopulacione hibridizacije u stresnim uslovima veliki uticaj ima poreklo ženke i evoluciona istorija njene prirodne populacije. Može se zaključiti da je održavanje genetičke varijabilnosti od velike važnosti za opstanak populacija, i da čak i nizak stepen inbridinga utiče na pad adaptivne vrednosti, naročito u stresnim uslovima sredine., The subject of this dissertation is population genetic analysis of synergistic effect of genomic and environmental stress in model species Drosophila subobscura. Individuals sampled from two ecologically distinct habitats, and their hybrids with different levels of genome heterozygosity (intra-line, intra-population and inter-population hybrids) were exposed to elevated concentrations of lead, aiming to test hypothesis of heterozygote superiority in stressful conditions and detect population specific response to lead pollution. Synergistic effect of stress was evaluated at three levels: population - through analysis of fitness components (development time and egg-to-adult survival), morphological - through analysis of variability in the wings size and biochemical – through the expression of heat shock protein. The results showed a reduction of all investigated traits in inbred individuals and their increase in those with higher levels of genome heterozygosity, confirming the hypothesis of heterozygote superiority which intensifies under stressful conditions. Analysis of fitness components indicates synergistic effect of genomic and environmental stress, and variance in wing size shows statistical significance, since the greatest reduction of all traits was observed in inbred groups. Population specific response to lead pollution was not detected, but significant influence of female origin on the outcome of between-population hybridization under stressful conditions was observed. It can be concluded that the maintenance of genetic variation is important for the survival of populations in changing environments, and even low levels of inbreeding lead to decline in adaptive value, especially in stressful environments.

Prema teorijskim očekivanjima seksualna selekcija može smanjivati mutaciona opterećenja u populacijama. Mužjaci koji su boljeg genetičkog kvaliteta bi trebalo da budu uspešniji u parenju u poređenju sa mužjacima lošijeg genetičkog kvaliteta. Na taj način ženke, prilikom izbora partnera za parenje, mogu da eliminišu one mužjake koji nose štetne alele, i da smanje mogućnost prenošenja štetnih alela u sledeću generaciju. Seksualna selekcija će redukovati mutaciona opterećenja i povećavati adaptivnu vrednost populacije, ako je većina mutacija štetna i za adaptivnu vrednost i za osobine koje utiču na uspešnost mužjaka u parenju. Istraživanja poslednjih godina su dala rezultate koji idu u prilog ovoj teoriji, ali i oprečne rezultate. Ovakva kontradiktornost proizilazi iz kompleksnosti problematike usled različitih reproduktivnih strategija vrsta, kao i različitih reproduktivnih strategija mužjaka i ženki. Takođe, osobine koje utiču na komponente adaptivne vrednosti, kao i na uspešnost u parenju, su veoma složene, pod determinacijom velikog broja gena, i u čijoj osnovi leže kompleksne genske interakcije. Iako se kao osobine koje su cilj seksualne selekcije najčešće analiziraju sekundarne polne karakteristike, i mnoge druge osobine određuju atraktivnost mužjaka. To su i morfološke, fiziološke, ponašajne i druge osobine koje utiču na uspešnost u parenju, a mogu se nazvati osobinama koje su zavisne od opšteg stanja mužjaka (eng. condition-dependent traits)..., According to theoretical predictions sexual selection can reduce mutational load in populations. Males of good genetic quality should be more successful in matings, compared to the males of low genetic quality. In this way females, through the choice of mating partners, can eliminate males carriers of deleterious alleles, and reduce transmission of deleterious alleles to the next generation. Sexual selection will purge mutational load and increase fitness if most mutations were deleterious to both nonsexual fitness and condition-dependent traits affecting mating success. Studies in recent years have yielded results that support this theory, but opposite results are obtained, as well. This contradiction arises from different reproductive strategies of species, and different reproductive strategies of males and females. Traits that affect fitness components, as well as mating success, are under polygenic determination, with very complex gene interactions. Although secondary sexual traits were usually analyzed as target of sexual selection, many other traits can determine male attractiveness. Traits such as morphological, physiological, behavior and other, affecting mating success, can be termed as condition-dependent traits. In order to test this hypothesis, that sexual selection can reduce mutational load, two experimental groups were formed from the same population genetic pool of Drosophila subobscura, which differed in the level of mutational load. Mutations were induced in one group, using 30Gy ionizing radiation. The effect of sexual selection in reduction of mutational load was measured through different components of male mating behavior (courtship occurrence, courtship latency, courtship intensity, mating occurrence,latency to mating and duration of mating)....

Drosophila subobscura je vrsta sa širokim Palearktičkim rasprostranjenjem. Naseljava gotovo ceo evropski kontinent, severnu Afriku, Malu Aziju i neka atlanska ostrva. Genetička struktura prirodnih populacija ove vrste je opisana upotrebom nekoliko genetičkih markera. Najtemeljnije je izučena varijabilnost hromozomskog inverzionog polimorfizma, po kome populacije D. subobscura pokazuju prostornu i vremensku struktuiranost. Klinalni obrasci ovog tipa varijabilnosti upućuju na značaj selektivnih procesa u njenom oblikovanju, dok razlike između geografski bliskih područja između kojih postoji geografska barijera upućuju na značaj istorijskih procesa. Naime, uočena varijabilnost oslikava procese rekolonizacije Evrope nakon završetka poslednje glacijacije iz primarnog pribežišta lociranog u regionu koji obuhvata Balkan, Malu Aziju i Kavkaz, ali i sekundarnog u regionu Pirinejskog poluostrva. Mikrosatelitska varijabilnost izučavana je u nekoliko evropskih populacija D. subobscura, uglavnom iz zapadnog dela Evrope. Pokazano je da su populacije slabo struktuirane po ovom genetičkom markeru. Populacije u južnom delu areala odlikuju se nešto većom genetičkom raznovrsnošću. Donekle je slična i slika varijabilnosti prirodnih populacija po mitohondrijalnoj DNK (mtDNK), u slučaju koje je zabeležena homogenost distribucije haplotipova između populacija. U velikoj većini do sada analiziranih populacija zabeleženo je prisustvo dva dominantna haplotipa i veliki broj endemičnih haplotipova niske učestalosti. Pokazano je da nekoliko faktora oblikuje varijabilnost mtDNK D.subobscura. Među njima su najznačajniji istorijski procesi, genetički drift, i prirodna selekcija koja najverovatnije deluje preko cito-nukleusne koadaptacije između alelskih kombinacija u okviru inverzija i mtDNK varijanti..., Drosophila subobscura shows a wide Palearctic distribution. It inhabits most of Europe, Northern Africa, Asia Minor and some Atlantic islands. The genetic structure in natural populations of this species has been extensively studied with respect to several genetic markers. The variability of chromosomal inversion polymorphism has been most thoroughly studied showing spatial and temporal structure in natural populations. The clinal pattern of chromosomal variability suggests the action of natural selection on inversion polymorphism, while abrupt changes in gene arrangement frequencies between closely related populations separated by geographical barrier suggest the importance of historical processes on the genetic structure. After the decay of the ice caps, Drosophila subobscura, most probably, recolonized Europe mainly from the Balkan Peninsula, Asia Minor and Caucasus, but also, to a lesser degree, from the Iberian Peninsula. Several populations of D. subobscura, mostly from the Western Europe, have been studied with respect to microsatellite variability. The analysis showed absence of structuring of genetic variation, with slightly higher genetic variability in Southern populations. There is a widespread genetic homogeneity of mitochondrial DNA (mtDNA) variability throughout the species range with high prevalence of two almost equally frequent haplotypes, and a number of population specific, rare haplotypes. Several factors account for the observed distribution in mtDNA variability: historical processes, genetic drift and natural selection, most probably acting through cytonuclear coadaptation of alleles inside inversions and mtDNA haplotypes...

Chromosomal inversion polymorphism play a major role in the evolutionary dynamics of populations and species because of their effects on the patterns of genetic variability in the genomic regions within inversions. Though there is compelling evidence for the adaptive character of chromosomal polymorphisms, the mechanisms responsible for their maintenance in natural populations is not fully understood. For this type of analysis, Drosophila subobscura is a good model species as it has a rich and extensively studied chromosomal inversion polymorphism system. Here, we examine the patterns of DNA variation in two natural populations segregating for chromosomal arrangements that differentially affect the surveyed genomic region; in particular, we analyse both nucleotide substitutions and insertion/deletion variations in the genomic region encompassing the odorant-binding protein genes Obp83a and Obp83b (Obp83 region). We show that the two main gene arrangements are genetically differentiated, but are consistent with a monophyletic origin of inversions. Nevertheless, these arrangements interchange some genetic information, likely by gene conversion. We also find that the frequency spectrum-based tests indicate that the pattern of nucleotide variation is not at equilibrium; this feature probably reflects the rapid increase in the frequency of the new gene arrangement promoted by positive selection (that is an adaptive change). Furthermore, a comparative analysis of polymorphism and divergence patterns reveals a relaxation of the functional constraints at the Obp83b gene, which might be associated with particular ecological or demographic features of the Canary island endemic species D. guanche.

Adaptation to a new environment (as well as its underlying mechanisms) is one of the most important topics in Evolutionary Biology. Understanding the adaptive process of natural populations to captivity is essential not only in general evolutionary studies but also in conservation programmes. Since 1990, the Group of Experimental Evolution (CBA/FCUL) has been performing long-term, real-time evolutionary studies, with the characterization of laboratory adaptation in populations of Drosophila subobscura founded in different times and from different locations. Initially, these experiments involved phenotypic assays and more recently were expanded to studies at the molecular level (microsatellite and chromosomal polymorphisms) and with different population sizes. Throughout these two decades, a clear pattern of evolutionary convergence to long-established laboratory populations has been consistently observed in several life-history traits. However, contingencies across foundations were also found during the adaptive process. In characters with complex evolutionary trajectories, the data suggested that the comparative method lacked predictive capacity relative to real-time evolutionary trajectories (experimental evolution). Microsatellite analysis revealed general similarity in gene diversity and allele number between studied populations, as well as an unclear association between genetic variability and evolutionary potential. Nevertheless, ongoing studies in all foundations are being carried out to further test this hypothesis. A comparison between recently introduced and long-term populations (founded from the same natural location) has shown higher degree of chromosomal polymorphism in recent ones. Finally, our findings suggest higher heterogeneity between small-sized populations, as well as a slower evolutionary rate in characters close to fitness (such as fecundity and mating behaviour). This comprehensive study is aimed at better understanding the processes and pat

Adaptation to a new environment (as well as its underlying mechanisms) is one of the most important topics in Evolutionary Biology. Understanding the adaptive process of natural populations to captivity is essential not only in general evolutionary studies but also in conservation programmes. Since 1990, the Group of Experimental Evolution (CBA/FCUL) has been performing long-term, real-time evolutionary studies, with the characterization of laboratory adaptation in populations of Drosophila subobscura founded in different times and from different locations. Initially, these experiments involved phenotypic assays and more recently were expanded to studies at the molecular level (microsatellite and chromosomal polymorphisms) and with different population sizes. Throughout these two decades, a clear pattern of evolutionary convergence to long-established laboratory populations has been consistently observed in several life-history traits. However, contingencies across foundations were also found during the adaptive process. In characters with complex evolutionary trajectories, the data suggested that the comparative method lacked predictive capacity relative to real-time evolutionary trajectories (experimental evolution). Microsatellite analysis revealed general similarity in gene diversity and allele number between studied populations, as well as an unclear association between genetic variability and evolutionary potential. Nevertheless, ongoing studies in all foundations are being carried out to further test this hypothesis. A comparison between recently introduced and long-term populations (founded from the same natural location) has shown higher degree of chromosomal polymorphism in recent ones. Finally, our findings suggest higher heterogeneity between small-sized populations, as well as a slower evolutionary rate in characters close to fitness (such as fecundity and mating behaviour). This comprehensive study is aimed at better understanding the processes and pat

Mitochondria are cellular organelles that have the function of the oxidative phosphorilation and the formation of ATP. In humans, the mtDNA is a double-stranded, circular, covalent closed molecule of 16.5 kb. The mtDNA is inherited as a haploid from the mother and heteroplasmy has been found rarely. From a populational perspective, it could be considered as a system of small, sexually isolated demes, or clonal lineages, with an evolutionary rate 5 to 10 times faster than the nuclear genome. All these characteristics make this molecule ideal for evolutionary studies. We present two applications of this molecule in genetical studies. One of these is referred to the Balearic Islands populations, Majorca, Minorca, Ibiza, and Chuetas. The other example is the populational dynamics of the different mitochondrial haplotypes in Drosophila subobscura. We also discuss the importance of nuclear markers to complete these studies as well as the study of the Y chromosome to compensate the bias produced by the study of only the mtDNA.

U sаvrеmеnој biоlоgiјi оpštе је prihvаćеn stаv dа sе оrgаnizmi i pоpulаciје nе mоgu pоsmаtrаti izvаn svојih srеdinа. U dinаmici gеnоfоndа pоpulаciје znаčајаn је stеpеn uspеšnоsti оdgоvоrа rаzličitih gеnоtipоvа nа prоmеnе uslоvа srеdinе. Stоgа је sаglеdаvаnjе mоgućih vidоvа intеrаkciје rаzličitih gеnоtipоvа i srеdinа znаčајnо zа rаzumеvаnjе mikrоеvоluciоnih prоcеsа kојi sе оdigrаvајu u оkviru prirоdnih pоpulаciја. Јеdinkе istе vrstе, čiје је rаzvićе u rаzličitim srеdinаmа, mоgu sе znаčајnо rаzlikоvаti pо fеnоtipskim kаrаktеrimа. Оvаkvа fеnоtipskа difеrеnciјаciја izmеđu grupа јеdinki čiје sе rаzvićе оdviјаlо u rаzličitim stаništimа, mоžе biti uzrоkоvаnа gеnеtičkim rаzlikаmа izmеđu grupа, ili isklјučivо еfеktimа srеdinе nа fеnоtip јеdinki. Pоstојаnjе јаsnе biоhеmiјskо – fiziоlоškе ulоgе α–аmilаzе i јаsnо dеfinisаnоg supstrаtа njеnоg dеlоvаnjа pružа mоgućnоsti dа sе sаglеdајu mоgući vidоvi intеrаkciје rаzličitih gеnоtipоvа i srеdinе, štо mоžе biti оd znаčаја zа rаzumеvаnjе mikrоеvоluciоnih prоcеsа kојi sе оdigrаvајu u оkviru prirоdnih pоpulаciја. Pоlimоrfizаm Amy–lоkusа kоd Drosophila subobscura uzеt је kао mоdеl sistеm zа еkspеrimеntаlnо pоpulаciоnо – gеnеtičkо rаzmаtrаnjе stеpеnа uspеšnоsti оdgоvоrа rаzličitih gеnоtipоvа nа vrstu i brzinu prоmеnе srеdinе, kаkо bi sе rаzmаtrаli оblici, prаvci i еfеkti intеrаkciје gеnоtip/srеdinа. U nаšim istrаživаnjimа аnаlizirаn је uticај rаzličitih kоncеntrаciја skrоbа kао i uticај pоstеpеnih i nаglih prоmеnа kоncеntrаciје skrоbа nа kоmpоnеntе аdаptivnе vrеdnоsti. Dužinа rаzvićа i prеživlјаvаnjе, pоrеd spеcifičnе аktivnоsti α–аmilаzе kоd јеdinki Drosophila subobscura hоmоzigоtnih ili hеtеrоzigоtnih zа “spоri” ili “brzi” аmilаzni аlеl, mоgu biti tаkоđе vаlidni pоkаzаtеlјi nаčinа оdgоvоrа nа rаzličitе kоncеntrаciје skrоbа u mеdiјumu nа kоmе јеdinkе kоmplеtirајu živоtni ciklus. Nоrmе rеаkciја zа prоsеčnе vrеdnоsti аnаlizirаnih kаrаktеristikа ukаzuјu nа pоstојаnjе znаčајnоg srеdinskоg uticаја kао i dа је u njihоvој оsnоvi gеnеtičkа vаriј, In modern biology, it is the generally accepted that organisms and populations can not be observed separately from their environments. Effectiveness of responses of different genotypes to environmental changes is essential for the dynamics of population gene pool. Therefore, consideration of the possible forms of interaction among different genotypes and environments is important for understanding microevolutionary processes occurring within natural populations. Individuals of the same species that develop in different environments, can significantly differ phenotypically. This phenotypic differentiation can be caused by genetic differences between the groups or environmental effects. The existence of clear biochemical - physiological role of α–amylase and clearly defined substrate of its action allows the analysis of possible interactions between different genotypes and environment, which can be significant for understanding of microevolutionary processes occurring within natural populations. Polymorphism of Amy–locus in Drosophila subobscura is taken as a model system for the experimental population – genetic study the effectiveness of responses of different genotypes to type and dynamic of environmental changes, to consider forms, directions and effects of genotype/environment interactions. Our research deals with the effects of different starch concentrations, as well as gradual and abrupt changes of starch concentrations on fitness components. Development time, viability and specific activity of α–amylase in Drosophila subobscura, which are homozygous or heterozygous for “slow” or “fast” amylase allele, can also be good indicators of response to different concentrations of starch in substrate on which life cycle of individuals is completed. Obtained reaction norms, for the average values of analyzed traits, reveal significant environmental effect and the presence of genetic variability of Drosophila subobscura individuals. Based on the analysis of responses of