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21.
Jorge E. Ramos Gretta T. Pecl Natalie A. Moltschaniwskyj Jan M. Strugnell Rafael I. León Jayson M. Semmens 《PloS one》2014,9(8)
Understanding the response of any species to climate change can be challenging. However, in short-lived species the faster turnover of generations may facilitate the examination of responses associated with longer-term environmental change. Octopus tetricus, a commercially important species, has undergone a recent polewards range shift in the coastal waters of south-eastern Australia, thought to be associated with the southerly extension of the warm East Australian Current. At the cooler temperatures of a polewards distribution limit, growth of a species could be slower, potentially leading to a bigger body size and resulting in a slower population turnover, affecting population viability at the extreme of the distribution. Growth rates, body size, and life span of O. tetricus were examined at the leading edge of a polewards range shift in Tasmanian waters (40°S and 147°E) throughout 2011. Octopus tetricus had a relatively small body size and short lifespan of approximately 11 months that, despite cooler temperatures, would allow a high rate of population turnover and may facilitate the population increase necessary for successful establishment in the new extended area of the range. Temperature, food availability and gender appear to influence growth rate. Individuals that hatched during cooler and more productive conditions, but grew during warming conditions, exhibited faster growth rates and reached smaller body sizes than individuals that hatched into warmer waters but grew during cooling conditions. This study suggests that fast growth, small body size and associated rapid population turnover may facilitate the range shift of O. tetricus into Tasmanian waters. 相似文献
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Jacek Kęsy Beata Maciejewska Magdalena Sowa Magdalena Szumilak Krzysztof Kawałowski Maja Borzuchowska Jan Kopcewicz 《Plant Growth Regulation》2008,55(1):43-50
It has been shown that both IAA and ethylene application inhibit flower induction in the short-day plant Pharbitis nil. However application of IAA has elevated ethylene production in this plant, as well. Strong enhancement of ethylene production
is also correlated with the night-break effect, which completely inhibits flowering. In order to determine what the role of
IAA and ethylene is in the photoperiodic flower induction in Pharbitis nil, we measured changes in their levels during inductive and non-inductive photoperiods, and the effects of ethylene biosynthesis
and action inhibitors on inhibition of flowering by IAA. Our results have shown that the inhibitory effect of IAA on Pharbitis nil flowering is not physiological but is connected with its effect on ethylene biosynthesis. 相似文献
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In this study we simulated the invasion of Heracleum mantegazzianum with a spatiotemporal model that combined a life-cycle matrix model with mechanistic local and corridor dispersal and a stochastic long-distance dispersal in a cellular automaton. The model was applied to the habitat configuration and invader distribution of eight 1?km2 study areas. Comparing the simulations with monitoring data collected over 7?years (2002?C2009) yielded a modelling efficiency of 0.94. We tested the significance of different mechanisms of invasion by omitting or modifying single model components one at a time. Thus we found that the extent of H. mantegazzianum invasion at landscape level depends on both landscape-scale processes and local processes which control recruitment success and population density. Limiting recruitment success (100????30?%) and successionally decreasing the carrying capacity of habitats (max????0) over 30?years significantly improved the projections of the invasion at the landscape level. Local dispersal reached farther than 10?m, i.e. farther than previously assumed, but appeared to be unaffected by wind directions. Long-distance dispersal together with local dispersal dominated the invasion quantitatively. Dispersal through corridors accounted for less invasive spread. Its importance, with respect to invasion speed (number of colonised model grid cells) is probably limited over short periods of time (7?years). Only dispersal along rivers made a significant quantitative contribution to invasion of H. mantegazzianum. We suggest that biotic heterogeneity of suitable habitats is responsible for varying invasion success and that successionally increasing competition leads to declining population densities of H. mantegazzianum over several decades slowing down the spread on the landscape scale. 相似文献
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Preferential expression of cellular retinoic acid binding protein in a subpopulation of neural cells in the developing mouse embryo 总被引:2,自引:0,他引:2
Marie-Josée Vaessen Erika Kootwijk Dirk Bootsma Ad Geurts van Kessel Christine Mummery John Hilkens 《Differentiation; research in biological diversity》1989,40(2):99-105
The cellular retinoic acid binding protein is thought to be involved in the retinoic-acid-mediated signal transduction pathway. We have isolated the mouse cellular retinoic acid binding protein cDNA from an embryonal-carcinoma-derived cell line by using differential cDNA cloning strategies. In situ hybridization on sections of mouse embryos of various developmental stages indicated that the cellular retinoic acid binding protein gene, which we localized on mouse chromosome 9, is preferentially expressed in a subpopulation of neurectodermal cells. This restricted expression pattern suggests an important role for cellular retinoic acid binding protein in murine neurogenesis. 相似文献
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