So shark dive clubs usually bring some fishy scraps—in most cases the remains left over after big fish have been cut up for sale. The scent attracts the sharks into view and provides a bit of excitement as the animals investigate and try to get a piece. But little actual food or nourishment is given. The sharks circle far and wide through the vast volume of the visible ocean, in a memorable and dramatic display, as they look over the scene, zoom in for a closer look, try for a scrap, and socialize.

The 10,850-ton armoured cruiser HMS Hampshire departed Scapa Flow in Orkney on 5 June 1916 on a voyage around the north cape of Norway to the port of Archangel in northern Russia. She was carrying Lord Kitchener, the Secretary of State for War, and his staff to Russia to discuss mutual war aims and strategy.

Antioxidant capacity is a critical component of stress tolerance because in a range of organisms, including corals, stressors such as high water temperature, poor water quality and even pathogen infection, produce an increase in damaging, highly reactive oxygen molecules (free radicals) inside the tissues.

The ability to tolerate environmental stress varies between individuals, so the team associated with the Australian Institute of Marine Science set out to find the most stress-tolerant of the common reef-building coral Acropora millepora.

After combing through more than 2,000 articles and conducting a systematic review of the evidence for the use of heat or ice in the treatment of cnidarian envenomations, the team concluded that the majority of studies to date support the use of hot-water immersion for pain relief and improved health outcomes.