Loggerhead sea turtle adult males have thicker tails and shorter plastrons (lower shells) than the females. The loggerhead sea turtle is found in the Atlantic, Pacific, and Indian Oceans, as well as the Mediterranean Sea. It spends most of its life in saltwater and estuarine habitats, with females briefly coming ashore to lay eggs. The loggerhead sea turtle has a low reproductive rate; females lay an average of four egg clutches and then become quiescent, producing no eggs for two to three years. The loggerhead reaches sexual maturity within 17–33 years and has a lifespan of 47–67 years. The loggerhead sea turtle is
Varieties of Chinese increase, although there are also some sharp boundaries. However, the rate of change in mutual intelligibility varies immensely depending on region. For example, the varieties of Mandarin spoken in all three northeastern Chinese provinces are mutually intelligible, but in the province of Fujian, where Min varieties predominate, the speech of neighbouring counties or even villages may be mutually unintelligible. Classifications of Chinese varieties in the late 19th century and early 20th century were based on impressionistic criteria. They often followed river systems, which were historically the main routes of migration and communication in southern China. The first scientific classifications, based