Evolution of exceptional species richness among lineages of fleshy-fruited Myrtaceae

MethodsBayesian phylogenetic analyses of plastid and nuclear DNA sequences were used to estimate intertribal relationships and lineage divergence times in Myrtaceae. Focusing on the fleshy-fruited tribes, a variety of statistical approaches were used to assess diversification rates and diversification rate shifts across the family.ConclusionsFleshy fruits have evolved independently in Syzygieae and Myrteae, and this is accompanied by exceptional diversification rate shifts in both instances, suggesting that the evolution of fleshy fruits is a key innovation for rainforest Myrtaceae. Noting the scale dependency of this hypothesis, more complex explanations may be required to explain diversification rate shifts occurring within the fleshy-fruited tribes, and the suggested phylogenetic hypothesis provides an appropriate framework for this undertaking.     

Establishment and growth of hawthorn in floodplains in the Netherlands

Dendrochronology was used to assess the influence of soil conditions, elevation and related inundation, climate fluctuations and vegetation cover on the establishment and growth of hawthorn in non-grazed river floodplains. Presence of forest influences the discharge capacity of the floodplain, therefore forest development needs to be considered in management plans. Although ring detection in hawthorn is difficult, clear dynamics in establishment and growth of this shrub species were found. Establishment was mainly influenced by inundation (length and height). The effect of inundation on establishment is location dependent; positive due to transport and deposition of seeds in higher areas, and negative due to drowning of young plants in lower locations. Extreme climatic events were found to influence establishment including a drought in 2003 and relatively low and high precipitation in 2004–2006 and 2007 respectively. These events combined with almost no inundation caused some anomalies in the time series for hawthorn establishment. Once above a certain height, hawthorn is able to withstand various abiotic disturbances occurring in these dynamic river floodplains. Excavated areas are enhancing forest development following hawthorn establishment and therefore these areas should be limited in size (e.g. by deeper and narrower excavations and thus a steeper transition towards the grasslands).     

A new cryptic Sympistis from eastern North America revealed by novel larval phenotype and host plant association (Lepidoptera,Noctuidae, Oncocnemidinae)

A Triosteum-feeding species of Sympistis is described from eastern North America: Sympistis forbesi sp. n. Identity of the new species is most reliably determined from larval morphology and host plant association—both adult scaling and genitalic characters overlap with those of Sympisitis chionanthi, a Chionanthus and Fraxinus feeder.     

The Rate of Cu,Zn Superoxide Dismutase Evolution

The rate of amino acid replacement in Cu, Zn SOD greatly departs from the expectations of the molecular clock. We examine 27 Cu, Zn SOD sequences available and conclude that: (I) the SOD enzymes from different mammal families differ from each other by roughly the same number of replacements, which is consistent with a simultaneous mammalian radiation; (2) over the most recent 60 million years (MY) the rate of SOD evolution is fairly high (15aa/100aa/100MYR) and may be considered constant; (3) the rate of accumulation of amino acid replacements since the divergence of fungi. plants and animals to the present is inconstant along different branches of the evolutionary tree; moreover it steadily decreases with time, to the same extent in all lineages; (4) some comparisons exhibit divergences that are in any case greater than expected from a Poisson process on the assumption of a molecular clock; (5) plant chloroplast enzymes display fewer differences from each other than cytoplasmic ones; (6) bacteriocuprein (from Photobacterium leiognathi), fluke and human extracellular SOD are all three extremely remotely related to one another and to the SOD of other eukaryotes.

The process of consistent decline of the rate of evolution of Cu. Zn SOD can be described by a number of mathematical functions. We explore simple models that assume constant rates and might be applicable to other proteins or genes that apparently evolve at disparate rates.     

Gene order and recombination rates in the linkage group S-Phi-Hal-H-(Po2)-Pgd in pigs

Families of Czech Landrace (94 litters and 636 offspring) were tested for halothane sensitivity, A-O (S), H, PHI and PGD phenotypes. Informative matings for the estimation of recombination rates between marker loci were selected. The following recombination frequencies were established: S-Phi = 4.8 % (2.5 % -10.7 %);S-H = 6.8 % (4.3 %-11.7 %); Phi-H = 2.6 % (0.9 %-5.3 9%); H-Pgd = 4.4 % (1.6 %-8.0 %). CCCC-overs were observed also between S- Hal, Hal-H andHal - Pgd, but were not found between Phi - Hal. On the basis of these results it has been possible to revise the position of the S locus in this linkage group. The most probable gene order would be: S - Phi - Hal (or Hal - Phi) -H- (P02) - Pgd.
A striking difference was found between the number of halothane-sensitive pigs (87) and HalⁿHal ⁿ genotypes determined by haplotyping (123). Segregation rates in 19 backcross matings and experimental matings of the animals proved that this difference is mostly due to incomplete CCC or low expression of halothane sensitivity.     

非人类物种的城市化:动物也是地球上的一员

提出在日益城市化进程中人类与非人类物种之间关系的4种推测。由于非人类物种也在快速城市化,它们的空间条件大部分都是由人类为自己所构建,这可以集中并强化拉图尔的生物共生理念。风景园林师应该理清自己工作的政治影响,而其中的一种方法是处理物种之间微妙而脆弱的相互关系。当然,采用未经验证的新自由主义设计在大多数情况下对非人类物种都会带来特殊的破坏性后果。本文使用“基础设施”模型探讨不同的生物群体之间如何相互影响彼此的命运。