Chrysanthemum white rust Chrysanthemum white rust Chrysanthemum white rust is a disease of plants caused by the fungus Puccinia horiana that infects species of the genus "Chrysanthemum". Chrysanthemum white rust was first identified in Japan, although it is now established throughout Asia, Europe, South America. It has been found in the United States, Australia, and New Zealand on several occasions, but early detection and eradication efforts have prevented the disease from becoming established in these countries. Plants infected by chrysanthemum white rust exhibit spots on the upper surfaces of leaves. These spots are initially pale-green to yellow in color and up to 5mm
Four causes after the ethologist Nikolaas Tinbergen and based on Aristotle's four causes, are complementary categories of explanations for animal behaviour. They are also commonly referred to as levels of analysis. The four questions are on function, what an adaptation does that is selected for in evolution; phylogeny, the evolutionary history of an organism, revealing its relationships to other species; mechanism, namely the proximate cause of a behaviour, such as the role of testosterone in aggression; and ontogeny, the development of an organism from egg to embryo to adult. Four causes The "four causes" are elements of an influential principle in Aristotelian