Ichthyology and GIS Ichthyology and GIS A Geographic Information System is a tool for mapping and analyzing data. The ability to layer many features onto the same map and select or unselect as needed allows for a multitude of views and ease of interpreting data. More important, this allows for in depth scientific analysis and problem solving. Ichthyology involves many areas of study related to fishes and their habitat. The natural habitat is water, but fish are dependent upon many other factors. Water quality, type, food, cover, sediment are essential for the life cycle of any given fish. Being able to map the
What Is and What Should Never Be and What Should Never Be" was performed live at Led Zeppelin concerts between 1969 and 1973. A live version taken from a performance at the Royal Albert Hall in 1970 can be seen on the "Led Zeppelin DVD". Another was included on disc two of the live triple album "How The West Was Won". Two more versions were included in BBC Sessions. What Is and What Should Never Be "What Is and What Should Never Be" is a song by English rock band Led Zeppelin. It was written by Jimmy Page and Robert Plant and was included as the second