Polymorphic microsatellite loci were characterised for two louse species, the anopluran Polyplax serrata Burmeister, 1839, parasitising Eurasian field mice of the genus Apodemus Kaup, and the amblyceran Myrsidea nesomimi Palma et Price, 2010, found on mocking birds endemic to the Galápagos Islands. Evolutionary histories of the two parasites show complex patterns influenced both by their geographic distribution and through coevolution with their respective hosts, which renders them prospective evolutionary models. In P. serrata, 16 polymorphic loci were characterised and screened across 72 individuals from four European populations that belong to two sympatric mitochondrial lineages differing in their breadth of host-specificity. In M. nesomimi, 66 individuals from three island populations and two host species were genotyped for 15 polymorphic loci. The observed heterozygosity varied from 0.05 to 0.9 in P. serrata and from 0.0 to 0.96 in M. nesomimi. Deviations from the Hardy-Weinberg equilibrium were frequently observed in the populations of both parasites. Fst distances between tested populations correspond with previous phylogenetic data, suggesting the microsatellite loci are an informative resource for ecological and evolutionary studies of the two parasites., Jana Martinů, Veronika Roubová, Milena Nováková, Vincent S. Smith, Václav Hypša, Jan Štefka., and Obsahuje bibliografii
The complete mitochondrial genome (mitogenome) of Spilarctia robusta (Lepidoptera: Noctuoidea: Erebidae) was sequenced and analyzed. The circular mitogenome is made up of 15,447 base pairs (bp). It contains a set of 37 genes, with the gene complement and order similar to that of other lepidopterans. The 12 protein coding genes (PCGs) have a typical mitochondrial start codon (ATN codons), whereas cytochrome c oxidase subunit 1 (cox1) gene utilizes unusually the CAG codon as documented for other lepidopteran mitogenomes. Four of the 13 PCGs have incomplete termination codons, the cox1, nad4 and nad6 with a single T, but cox2 has TA. It comprises six major intergenic spacers, with the exception of the A+T-rich region, spanning at least 10 bp in the mitogenome. The nucleotide composition of the genome is greatly A+T biased (81.09%), with a negative AT skewness (-0.007), indicating the presence of fewer As than Ts, similar to other Noctuoidea. The A+T-rich region is 343 bp long, and contains some conserved regions, including an "ATAGA" motif followed by a 19 bp poly-T stretch, a microsatellite-like (AT)9 and a poly-A element, a characteristic shared with other lepidopteran mitogenomes. Phylogenetic analysis, based on 13 PCGs using Maximum likelihood methods revealed that S. robusta belongs to the superfamily Noctuoidea., Yu Sun, Sen Tian, Cen Qian, Yu-Xuan Sun, Muhammad N. Abbas, Saima Kausar, Lei Wang, Guoqing Wei, Bao-Jian Zhu, Chao-Liang Liu., and Obsahuje bibliografii
Efficient degradation of damaged D1 during the repair of PSII is carried out by a set of dedicated FtsH proteases in the thylakoid membrane. Here we investigated whether the evolution of FtsH could hold clues to the origin of oxygenic photosynthesis. A phylogenetic analysis of over 6000 FtsH protease sequences revealed that there are three major groups of FtsH proteases originating from gene duplication events in the last common ancestor of bacteria, and that the FtsH proteases involved in PSII repair form a distinct clade branching out before the divergence of FtsH proteases found in all groups of anoxygenic phototrophic bacteria. Furthermore, we showed that the phylogenetic tree of FtsH proteases in phototrophic bacteria is similar to that for Type I and Type II reaction centre proteins. We conclude that the phylogeny of FtsH proteases is consistent with an early origin of photosynthetic water oxidation chemistry., S. Shao, T. Cardona, P. J. Nixon., and Obsahuje bibliografické odkazy
Lakušníky (Batrachium) patří k nejpozoruhodnějším rostlinám naší vodní flóry. Vyznačují se svéráznými adaptacemi na rozmanité vodní biotopy po morfologické i reprodukční stránce. Patří k taxonomicky nejkomplikovanějším skupinám vodních rostlin, s oblibou navzájem hybridizují a jejich evoluční historie je neobyčejně spletitá. Reprodukční systém jednotlivých druhů i charakter mezidruhové hybridizace je silně ovlivněn rozdílnou velikostí květů u jednotlivých druhů. Některé morfologicky definované druhy ve skutečnosti zahrnují několik kryptických taxonů, které se mohou lišit svým rozšířením. and In Europe, water-crowfoots (Ranunculus subg. Batrachium) are among the most taxonomically challenging plant groups. They are characterized by peculiar morphological and reproductive adaptations to the water environment. Because of frequent hybridization, their evolutionary history is extremely complicated. The species differ in flower size and the mode of reproduction. Several morphologically defined species include cryptic taxa, which may also differ in their geographic distribution.
Teploty vzduchu okolo 100 °C, erupce sopek, blesky, dopady masivních asteroidů, silné ultrafialové zářeni. Jak v takovém pekle na Zemi před čtyřmi miliardam ilet mohl vzniknou život? Otazek je více než odpovědí a pátrání po původu živoat zůstává dobrodružnou disciplínou, v níž spolu soupeří zastánci různých teorii. and Luděk Svoboda, Stanislava Kyselová.
Pohlavní rozmnožování je jednou z největších evolučních záhad. Mezi eukaryotickými organismy je široce rozšířené navzdory zásadním nevýhodám. V druhém díle článku se autor zaměřuje na vysvětlení tohoto paradoxu ze strany teorie zamrzlé plasticity, které shrnuje řadu výhod pohlavních druhů postulovaných dřívějšími teoriemi a vysvětluje je prostřednictvím evolučního zamrzání. To je vlastní pohlavním druhům a spočívá v dlouhodobém udržování vysokého genetického polymorfismu umožňujícího rychlé a vratné reakce na selekční tlaky prostředí na úkor schopnosti se nevratně přizpůsobit změněným podmínkám., Sexual reproduction is one of the major evolutionary enigmas. It is widely distributed among eukaryotic organisms despite its essential disadvantages. In the second part of his article, the author focuses on the explanation of this paradox according to the “frozen plasticity theory”, which connects several advantages of sexual organisms postulated by earlier theories and explicates them by evolutionary freezing. This phenomenon applies to sexual species and is based on long-term maintenance of high genetic polymorphism, which facilitate fast and reversible reactions to selective pressures of the environment at the expense of the ability to irreversibly adapt to changed conditions., and Jan Toman.
The oldest butterfly fossil known, which was formed about 55 Ma in what is now Denmark, is described. The fragments of its forewing venation indicates it belongs to the Hesperiidae. Further reconstruction indicates that it fits in the Coeliadinae and is close to the extant genera Hasora and Burara. It is here described as Protocoeliades kristenseni gen. et sp. n. It is the first butterfly fossil found on a continent (Europe) where its closest relatives do not currently occur. Its position on the phylogenetic tree of the Coeliadinae and its importance in understanding the time dimension in the evolution of butterflies, and their ecological and biogeographic implications are discussed., Rienk De Jong., and Obsahuje bibliografii
Polystomatid monogeneans have a wide diversity of life cycles correlated with the varied ecology and behaviour of their aquatic vertebrate hosts. Typically, transmission involves a swimming infective larva but most hosts are amphibious and invasion is interrupted when hosts leave water. A key life cycle adaptation involves a uterus that, in the most specialised cases, may contain several hundred fully-developed larvae prepared for instant host-to-host transmission. By contrast, one subfamily of the Polystomatidae - the Polystomoidinae, specific to chelonians (freshwater turtles) - has a simplified reproductive system without a uterus. Recently, Polystomoides nelsoni Du Preez et Van Rooyen, 2015 has been described with a uterus containing multiple eggs. The present study explores the exceptional interest of this parasite - for the functional biology of egg production, for the evolution of a reproductive system unique amongst ca 60 species in the subfamily, and for systematic relationships. A new genus is proposed, Uteropolystomoides gen. n., separate from the four currently-recognised genera Polystomoides Ward, 1917, Uropolystomoides Tinsley et Tinsley, 2016, Neopolystoma Price, 1939 and Polystomoidella Price, 1939 which lack a uterus. In addition, U. nelsoni (Du Preez et Van Rooyen, 2015) comb. n. has a suite of distinctive copulatory stuctures: a massive genital bulb with an exceptionally large number of very long genital spines and hyper-development of the vaginal openings. These characters set U. nelsoni apart from all other polystomoidines worldwide except Polystomoides multifalx Stunkard, 1924 and P. stunkardi Harwood, 1931. Missing data for these latter species preclude definitive assessment of inter-relationships but the distinguishing characters of U. nelsoni, especially the unique occurrence of the uterus, suggest a novel evolutionary pathway isolated from other lineages of polystomatids infecting chelonians., Richard C. Tinsley., and Obsahuje bibliografii