The deep-sea is the largest ecosystem on Earth but is one of the least understood environments. Its remoteness and difficulties encountered in its exploration excite human imagination. The deep-sea is covered with mystery that stimulates human desire for knowledge and for conquering the last remaining frontier on Earth. In these pages you will soon discover what is known on continental margin ecology, the variety of habitats which are featured there and the amazing diversity of species living there.

Quite recently, submersibles has given access to hotspots on continental margins, which represent some of the best mountain scenery on Earth, if it were not blanketed by water!Among those hotspots are cold seep ecosystems. Cold seeps refer to areas where hydrocarbon gases and oil seep out of sediments. These areas are home to many species that have not been observed anywhere else on Earth. Two such ecosystems are featured:

- Along the west african margin, a cold seep site discovered during the Biozaire program (know more about the program in the Science Area)

- In the Southwest Pacific, a cold seep site discovered during a NOAA/NIWA exploration of chemosynthetic ecosystems off New Zealand (know more about the program in the Science Area)