About 70% of our planet is covered by oceans and seas: large, full of life and mysterious. They are a source of food, way of transportation, oxygen producer, and more. But the sea is in danger: overfishing, plastic waste, acidification, species extinction. We need to better understand the marine life and deal with it in a sustainable way, because our life is closely linked to the sea. If it is sick, we cannot stay healthy.About 70% of our planet is covered by oceans and seas: large, full of life and mysterious. They are a source of food, way of transportation, oxygen producer, and more. But the sea is in danger: overfishing, plastic waste, acidification, species extinction. We need to better understand the marine life and deal with it in a sustainable way, because our life is closely linked to the sea. If it is sick, we cannot stay healthy.