Nature researcher in Iraklia island, Greece

Yiannis Gavalas, a principal of the only school in Iraklia island, explores on a hill in Iraklia island, Greece, on May 23, 2013. For over 20 years, Gavalas has been working in this tiny island covers an area of 18 square kilometers with more than 100 residents. He has recorded about 650 species of plants, 174 species of birds and 26 species of butterflies in his spare time. He has published a book about local butterflies and more will follow. (Xinhua/Liu Yongqiu)