Ichthyology and GIS critical to streamlining data collection in field endeavors and generating more accurate data sets. Ichthyology requires an understanding species geographic requirements. Fish require different abiotic environments or sediments for successful completion of biological life cycle based on species. Serious examinations of species should always include habitat because habitat differences create changes in population. Sediment could thereby be mapped and changes in sediment could easily be verified using previous records while simultaneously showing changes in resident fish populations. Various factors relating to the fish life cycle, such as food sources, migration patterns, changes in spawning grounds, could all be more accurately
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