History of the Republic of Venice of the Sea" ceremony was established in this period. Orseolo died in 1008. Venice's control over the Adriatic was strengthened by an expedition by Pietro's son Ottone in 1017, by which time Venice had assumed a key role in balancing power between the Byzantine and Holy Roman Empires. During the long Investiture Controversy, an 11th-century dispute between Henry IV, Holy Roman Emperor and Pope Gregory VII over who would control appointments of church officials, Venice remained neutral, and this caused some attrition of support from the Popes. Doge Domenico Selvo intervened in the war between the Normans of Apulia and
Sea urchins of the Gulf of California is a sea urchin endemic to the Gulf of California. Approximately 23 species of sea urchins, 3 species of heart urchins, and 9 species of sand dollars call the Gulf of California habitat their home. Where they are found throughout the Gulf of California, can be classified into three biogeographic regions called the Northern Gulf, Central Gulf, and Southern Gulf. Two other regions are also used to classify sea urchins and other marine animals, and are called the Southwest Baja California Sur Region and the Colorado River Delta Biosphere Reserve. World Distribution Acronyms are used by marine biologists to designate