Under pressure: Short‐ and long‐term response to predation varies in two populations of a live‐bearing fish

Ethology ◽  
2019 ◽  
Vol 126 (4) ◽  
pp. 463-475
Author(s):  
Eve A. Humphrey ◽  
Erica Crespi ◽  
Joseph Travis
Author(s):  
Elizabeth Montes de Oca Megías ◽  
Maricela Morera Pérez ◽  
Guillermo Noa Pedroso ◽  
Felipe Piñol Jiménez ◽  
Mildred Armenteros Torres

2002 ◽  
Vol 29 (12) ◽  
pp. 1465 ◽  
Author(s):  
Edwin Kraus ◽  
Margje Voeten ◽  
Hans Lambers

Autotoxicity and allelopathy affect the respiration and yield of GL66 and GL72, two populations of perennial ryegrass (Lolium perenne L. cv. S23) that were originally selected for contrasting rates of mature-leaf dark respiration under conditions where allelopathic effects could not occur and autotoxic effects were minimal. The aim of this study was to further investigate growth and biomass allocation of these two populations in relation to their autotoxic and allelopathic properties. To this end, plants were subjected to two conditions (monoculture and mixed culture) and two treatments (growth in 'renewed' and 'replenished' nutrient solution, allowing for short- and long-term accumulation of allelochemicals, respectively). The fast-respiring population, GL66, showed a reduced total yield due to allelopathic effects only when long-term accumulation of allelochemicals was allowed (mixed culture, replenished). However, short-term accumulation (mixed culture, renewed) of allelochemicals was sufficient to affect allocation of biomass to leaf sheaths. The slow-respiring population, GL72, suffered from autotoxicity only when long-term accumulation was allowed (monoculture, replenished), and from allelopathy under both short- and long-term accumulation (mixed culture, either renewed or replenished). The predominant allelopathic and autotoxic effect was on dry matter percentage and dry weight of leaf sheaths. We conclude that the roots of both populations release one or more chemical compounds that primarily affect biomass allocation to leaf sheaths, both of the same and of the other population. Sensitivity to the putative inhibitor(s) released by the other population was greater than sensitivity to the inhibitor(s) released by a population's own roots.


2006 ◽  
Vol 21 (2) ◽  
pp. E6 ◽  
Author(s):  
John R. Vender ◽  
Mary Hughes ◽  
Betsy D. Hughes ◽  
Sydney Hester ◽  
Stephen Holsenback ◽  
...  

ObjectIn this study the authors provide an assessment of intrathecal baclofen (ITB) therapy and evaluate patient outcomes and satisfaction.MethodsRecords for patients with multiple sclerosis who were selected as candidates for ITB therapy were reviewed for their response to test dose, surgical technique, surgery- and pump-related complications, and short- and long-term response to therapy. Family and caregiver assessments of the value of ITB therapy were also reviewed.ConclusionsIntrathecal baclofen therapy is safe and effective. Most patients and caregivers express satisfaction with the therapy and would recommend it to other patients. Spasm frequency appears to be the single most common variable positively affected by therapy.


1997 ◽  
Vol 48 (7) ◽  
pp. 1401-1406 ◽  
Author(s):  
P.E.H. Minchin ◽  
M.R. Thorpe ◽  
J.N. Wünsche ◽  
J.W. Palmer ◽  
R.F. Picton

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