To explore how plants may influence dispersal of their own seeds by manipulating the behavior and physiology of their dispersers, we studied the effect of a soluble chemical (or chemicals) in the fruits of Witheringia solanacea (Solanaceae), a Costa Rican cloud forest shrub, on passage of its seeds through the guts of one of its major dispersers, the Black—faced Solitaire, Myadestes melanops (Muscicapidae: Turdinae). Using artificial fruits containing natural seeds, we found that the presence of a crude pulp extract reduced the median seed retention time by nearly 50%. Estimation of seed dispersal distance as a function of retention time suggested that more rapid seed passage results in shorter average dispersal distances, especially for seeds retained <20 min. At the same time, germination trials revealed that seeds voided rapidly were far more likely to germinate than those remaining longer in Myadestes guts. We propose that “laxative” chemical(s) in Witheringia fruits balance these positive and negative consequences of ingestion by Myadestes.

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Patients with a history of depression who were not receiving antidepressants and active IDUs are more likely to fail treatment for genotype 2/3 HCV and will need additional support.

In this observational study, higher baseline neutrophil count and fall of neutrophil count during the treatment of hepatitis C was associated with achieving sustained virological response. These findings could have important implications for the monitoring and management of HCV treatment with peginterferon if they are confirmed in other studies.

In this study, we explore the reproductive biology of Cercocarpus ledifolius (Rosaceae), a species showing extremely limited recruitment throughout its range in the Intermountain West, USA. We examined (1 1 self-compatibility, (2) the potential for wind pollination, (3) pollen limitation of seed production, and (4) loss of developing seeds. Through hand-pollination experiments, we determined that C. ledifolius flowers are highly self-compatible. Abundant seeds were produced from flowers pollinated with pollen from the same plant, and the level of seed production did not differ from control outcrossed treatments. Furthermore, we measured substantial airborne pollen loads within C. ledifolius stands, indicating transport of pollen via wind and a strong potential for wind pollination, despite apparent adaptations for insect pollination. Pollen did not limit seed production; branches on which all flowers were handpollinated with outcrossed pollen did not have greater seed production than control branches open only to natural pollination. Lastly, virtually all initiated seeds developed t o maturity, indicating low seed abortion rates and minimal loss t o pre-dispersal seed predators. Natural levels of fruit production were at or greater than mean fruit production for woody perennials. In summary, we found no evidence that the quantity of pollen, the source of pollen (self vs. outcrossed), or developing seed loss is seriously limiting recruitment of this species.