The basic idea of evolutionary game theory is that payoff determines reproductive rate. Successful individuals have a higher payoff and produce more offspring. But in evolutionary and ecological situations there is not only reproductive rate but also carrying capacity. Individuals may differ in their exposure to density limiting effects. Here we explore an alternative approach to evolutionary g...

Efforts to understand the ecological regulation of species diversity via bottom-up approaches have failed to yield a consensus theory. Theories based on the alternative of top-down regulation have fared better. Paine's discovery of keystone predation demonstrated that the regulation of diversity via top-down forcing could be simple, strong, and direct, yet ecologists have persistently failed to...

every time a visitor sets foot in an ecotourism site, he/she causes a negative impact. this is an unavoidable fact. an ecotourism program initiates many public use activities that will have impacts ,both positive and negative. an ecotourism management plan seeks to minimize the negative impacts.therefore monitoring and managing of visitor impacts are fundamental ecotourism management strategie...

one of the purposes of ecotourism is to relax and aspirate the natural energy. sacred and energetic sites are the locations for experiencing the relaxation. since 2005 the ecotourism for aspirating the natural energy or spiritual ecotourism has been developed in iran. there are some places in iran which have a kind of energy as subtle energy for increasing personal health and awareness. these p...