Using a Bull Call Spread

4 pp., 1 figure, 3 tablesThe Bull Call Spread can be used to hedge against or to benefit from a rising market. The user buys a call option at a particular strike price and sells a call option at a higher strike price. Margin requirements, advantages and disadvantages of this strategy are explained

The Minimum Price Contract

4 pp., 5 figuresA minimum price contract is one of many tools a marketer may use to better manage price and production risk while trying to achieve financial goals and objectives. This publication discusses the advantages and disadvantages involved in this marketing program and the situations when it can be used

Using a Bull Call Spread

4 pp., 1 figure, 3 tablesThe Bull Call Spread can be used to hedge against or to benefit from a rising market. The user buys a call option at a particular strike price and sells a call option at a higher strike price. Margin requirements, advantages and disadvantages of this strategy are explained

Using a Bear Put Spread

4 pp., 4 tables, 1 graphThe Bear Put Spread is an option spread that combines buying and selling put options of the same contract month. This publication discusses the advantages and disadvantages of this marketing tool

A tight association in two genetically unlinked dispersal related traits in sympatric and allopatric salt marsh beetle populations

Local adaptation likely involves selection on multiple, genetically unlinked traits to increase fitness in divergent habitats. Conversely, recombination is expected to counteract local adaptation under gene flow by breaking down adaptive gene combinations. Western European populations of the salt marsh beetle Pogonus chalceus are characterized by large interpopulation variation at various geographical ranges in two traits related to dispersal ability, i.e. wing size and different allozymes of the mitochondrial NADP?-dependent isocitrate dehydrogenase (mtIdh) gene. In this study, we tested whether variation in wing length was as strongly genetically determined in locally adapted populations in a sympatric mosaic compared to allopatric populations, and if variation in mtIDH and wing size was genetically unlinked. We demonstrate that the genetic determination of wing size is very high (h2 = 0.90) in sympatry and of comparable magnitude as geographically separated populations. Second, we show that, although frequencies of mtIDH allozymes are tightly associated with mean population wing size across Western European populations, the correlation is strongly reduced within some of the populations. These findings demonstrate that the divergence involves at least two traits under independent genetic control and that the genetically distinct ecotypes are retained at geographical distances with ample opportunity for gene flow