'So little we know': in submersibles revealing the deep sea

This month, AFP boarded one of two submersibles belonging to OceanX, a non-profit backed by billionaire Ray Dalio and his son that brings scientists onto its OceanXplorer ship to study the marine world. The ship boasts labs for genetic sequencing, a helicopter for aerial surveys and a remotely operated vehicle (ROV) capable of descending up to 6,000 metres (19,700 feet) under the ocean surface. Its two submersibles have everything from hydraulic collection arms and suction tubes to high-definition cameras...