Effects of physical interference on life history shifts in Daphnia pulex
نویسندگان
چکیده
منابع مشابه
Effects of physical interference on life history shifts in Daphnia pulex.
Daphnia pulex were reared in 50 ml flasks, each containing 1, 20 or 40 individuals, which were serially connected with a 20-mum mesh screens between, in order to examine the effect of physical interference due to crowding on shifts of life history traits throughout two consecutive generations. A flow-through system, designed to maintain a sufficient food supply and minimize the accumulation of ...
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The genetic covariance structure for life-history characters in two populations of cyclically parthenogenetic Daphnia pulex indicates considerable positive correlation among important fitness components, apparently at odds with the expectation if antagonistic pleiotropy is the dominant cause of the maintanence of genetic variation. Although there is no genetic correlation between offspring size...
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Asexual taxa are short-lived, suggesting that transitions to asexuality represent evolutionary dead-ends. However, with high rates of clonal origin and coexistence of asexuals and sexuals via selective asymmetries, asexuality may persist in the long term as a result of a dynamic equilibrium between clonal origin and extinction. Few such systems have been studied in detail. Here, we investigate ...
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Techniques were developed to study the effects of increased water temperature on certain zooplankters; specific studies were conducted on Daphnia pulex, an abundant and important zooplankter of the lower Columbia River. Study methods simulated prolonged exposure to constant high tempera· tures in thermal discharges and short exposures to increased temperatures in condensers of cooling systems. ...
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ژورنال
عنوان ژورنال: Journal of Experimental Biology
سال: 2009
ISSN: 1477-9145,0022-0949
DOI: 10.1242/jeb.031518