Beaver (Castor canadensis) activity creates wetland habitats with varying hydroperiods important in maintaining habitat diversity for pond‐breeding amphibians with significantly different breeding habitat requirements. We documented pond‐breeding amphibian assemblages in 71 freshwater wetlands in Acadia National Park, Maine, USA. Using 15 variables describing local pond conditions and wetland landscape characteristics, we developed a priori models to predict sites with high amphibian species richness and used model selection with Akaike's Information Criterion to judge the strength of evidence supporting each model. We developed single‐species models to predict wood frog (Rana sylvatica), bullfrog (R. catesbeiana), and pickerel frog (R. palustris) breeding site selection. Sites with high species richness were best predicted by 1) connectivity of wetlands in the landscape through stream corridors and 2) wetland modification by beaver. Wood frog breeding habitat was best predicted by temporary hydroperiod, lack of fish, and absence of current beaver activity. Wood frog breeding was present in abandoned beaver wetlands nearly as often as in nonbeaver wetlands. Bullfrog breeding was limited to active beaver wetlands with fish and permanent water. Pickerel frog breeding sites were best predicted by connectivity through stream corridors within the landscape. As beavers have recolonized areas of their former range in North America, they have increased the number and diversity of available breeding sites in the landscape for pond‐breeding amphibians. The resulting mosaic of active and abandoned beaver wetlands both supports rich amphibian assemblages and provides suitable breeding habitat for species with differing habitat requirements. Land managers should consider the potential benefits of minimal management of beavers in promoting and conserving amphibian and wetland diversity at a landscape scale.

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In noise we hear the possibility of a signal, indeed different signals, and in the multiplicity of signals we hear noise. With variation and selection comes dynamic evolution, a contingent state, one that could be otherwise. The term ‘polemogenous’ (from the French, polémogène) means that which generates polemics. And polemics are creative. If everyone, every system, were to reason in the same way, there would be silence. Every remark would be redundant, having no informational value. Thus noise is not bad. The essence of finance economics, like all that is social in nature, is a forming of meaning. Whatever cannot be formed meaningfully is not available to the system. This unavailability, as ‘noise’, is the dynamic difference (noise/information) that scintillates the system. Information, like morality, is polemogenous – it stirs contention. Without noise and the possibility of its conversion to information there would be no opportunities to exploit. This paper applies a systems theoretical understanding of observation to conceive of finance economics as the economy’s means of observing its noise and capitalizing on that polemic. Niklas Luhmann’s method is utilized to explicate some ideas on noise by financial economist Fischer Black, who suggests the incomprehensible is computable. This is finance. The fact that logical grounds, absolute deductions, and clear calculations are claimed to be rare in finance is no barrier to understanding it. Rather, this polyphonic and polemogenous information-selection is the ‘ground’ of finance, not as totalizing logic, but as different difference-production for the sake of deriving economic opportunity.