Pairs of cleaner fish cooperate and give better service on the coral reef

The Bluestreak cleaner wrasse (Labroides dimidiatus) helps other fish species by eating parasites from their skin. The cleaner's favourite food is, however, the nutrient-rich mucus layer that covers the client fish.

Bluestreak cleaner wrasse eat parasites that have attached themselves to the client fish – but sometimes the cleaner fish can't resist the temptation to take a bite out of the client's mucus layer.

One of two stock anchor to be seen on the wreck

Kronprins Gustav Adolf maritime historical underwater park

The wreck lies in an area of approximately 100 square meters several nautical miles southwest of the lighthouse island of Harmaja at a depth of 18 to 20 meters. The site consists of the bottom of the hull, its sides (which have collapsed), parts of the upper structure of the ship, cannons, cannon balls, two big anchors and a variety of loose objects. There are usually no strong currents and the visibility is between one and ten metres.

No special permission by the Maritime Museum is needed for diving at the park during daytime in the summer.

Reef-forming sponges, Early Triassic era.
Reef-forming sponges, Early Triassic era.

Reefs recovered faster after mass extinction than first thought

Harsh living conditions caused by major fluctuations in the carbon content and sea levels, over-acidification and oxygen deficiency in the seas triggered the largest mass extinction of all time at the end of the Permian era 252 million years ago.

Life on Earth was also anything but easy after the obliteration of over 90 percent of all species: Throughout the entire Early Triassic era, metazoan-dominated reefs were replaced by microbial deposits. Researchers had always assumed it took the Earth as long as five million years to recover from this species collapse.