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Brady A. Porter Anthony C. Fiumera John C. Avise 《Behavioral ecology and sociobiology》2002,51(4):350-359
In a variety of fish species with paternal care of offspring, females prefer to spawn in nests that already contain eggs.
This female preference has been hypothesized to explain egg thievery in male sticklebacks, allopaternal care of eggs in minnows,
and the evolution of egg-mimicking body features in male cichlids and darters. Here we employ microsatellite-based parentage
analyses to evaluate the reproductive success of striped darter (Etheostoma virgatum) males that appear to utilize two of these functionally related tactics to entice females to spawn in their nests. In an
isolated population (Clear Creek, Ky.), we observed that breeding males develop conspicuous white spots on their pectoral
fins. If these spots are egg mimics, as we suspect, then this represents the fourth independent evolutionary origin of egg
mimicry documented to date in darters, the first based on pigmentation (as opposed to physical structures), and the first
in which the egg mimics vary greatly in number among males. From direct counts of microsatellite genotypes in clutches of
embryos, at least 3.8 females contributed to the progeny within a typical nest, and females tended to spawn preferentially
with males that were larger and displayed more egg-mimic spots. In another population (Hurricane Creek, Tenn.) without egg
mimics, the multi-locus genetic data document that allopaternal care is common, especially among the smallest males who sometimes
tend nests containing their own as well as an earlier sire's offspring. Thus, these foster males had adopted egg-containing
nests and then successfully spawned with subsequent females. Overall, the genetic data on paternity and maternity, in conjunction
with field observations, suggest that egg mimicry and allopaternal care are two mate-attracting reproductive tactics employed
by striped darter males to exploit female preferences for spawning in nests with 'eggs'.
Electronic Publication 相似文献
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Dickinson N Macpherson G Hursthouse AS Atkinson J 《Environmental geochemistry and health》2009,31(2):253-272
It is well documented that micronutrient malnutrition is of increasing concern in the developing world, resulting in poor
health and high rates of mortality and morbidity. During pregnancy, deficiency of iron and zinc can produce cognitive and
growth impairment of the foetus, which may continue into infancy. Iron and zinc are essential micronutrients for both plant
growth and human nutrition. Despite significant work in the areas of soil fertility, crop biofortification and dietary interventions,
the problems of micronutrient deficiencies persist in Africa. There is a need to examine why communities have not embraced
intervention strategies which may offer health benefits. Bottom-up, interdisciplinary approaches are required to effectively
study the relationships between local communities and their environment, and to assess the impact their behaviour has on the
cycling of micronutrients within the soil–plant–human system. From a detailed consideration of diverse influencing factors,
a methodological model is suggested for studying the barriers to improving micronutrient uptake within rural communities.
It combines environmental understanding with health and social factors, emphasising the need for and potential benefits of
understanding and coherence in true interdisciplinary working. 相似文献
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