Japan consists of approximately 7,000 islands and holds the distinction of being home to the largest islands in East Asia.

The nation’s geographic formation involved dynamic processes, contributing to its rich biodiversity and geological diversity.

Japan’s unique biota has been shaped by colonization from diverse sources, as well as cycles of isolation and reconnection of populations.

Recent discoveries highlight Japan’s role in reverse colonization, where species originating in Japan have recolonized continental regions.