Only 200 years ago, it was generally assumed that the deep sea was void of life. The deep seas were comparable to deserts; it was believed that no animal life existed at depths greater than 400 – 500 m.
The Challenger Expedition1872-76, Great Britain
The Expedition on the HMS Challenger stands apart as one of the most significant events in the history of marine science. Ship and crew were of the British Navy. The international staff of scientists were supervised by Professor Charles Wyville Thomson from Edinburgh, a specialist in the field of marine invertebrates.
The expedition explored depths, temperature, currents, and the biology of all world oceans, except the Arctic Ocean. The findings of the cruise were published over a period of 19 years in the series Report on the Scientific Results of the Voyage of H.M.S. Challenger In all 4 717 new species were described at this historic cruise.
The Michael Sars Expedition of 1910, Norway
The Michael Sars Expedition was a follow up of the Challenger expedition, only in a smaller capacity. It was a four-month cruise in the Atlantic Ocean in the spring and summer of 1910, exploring the North Atlantic south to Africa with the most modern ocean research vessel of the time, equipped for deep sea studies.
The expedition was jointly headed by the Norwegian scientist Johan Hjort together with the British oceanographer John Murray, who contributed with private funds. Murray had participated on the Challenger and had just finished the editing the multi-volume work on the scientific findings. He saw the Atlantic Ocean Expedition as an opportunity to pick up the threads after Challenger.
The cruise results were registered and catalogued by Bergen Museum, and is today one of the most valuable scientific collections at the Museum.
Is the Deep Sea without life?
Only 200 years ago, it was generally assumed that the deep sea was void of life. The deep seas were comparable to deserts; it was believed that no animal life existed at depths greater than 400 to 500 m.
The Norwegian scientist Michael Sars had by the middle of 1800s become an internationally celebrated scientist, based on his exceptional studies of marine animals. In collaboration with his Norwegian collegues, he collected marine animals from depths near to 1 000 m by means of a dredger, and the notion of the deep sea being similar to a desert seemed difficult to uphold much longer. In 1868 Sars was able to produce a list of 427 animal species caught alongside the Norwegian coast at depths of 450 fathoms, which equals about 820 m.
Michael Sars created quite a stir with his description of the “sea lily” Rhizocrinus lofotensis which his son, G.O.Sars, had found in 1864 at a depth of about 550 m in Lofoten. This strange echinoderm had a likeness to species which up to this date were known only from fossil finds. At a time when numerous diverging observations lent support to a developing evolutionary theory and evolution studies, the deep sea was by some natural history historians, seen as a possible link between past and present. Sars’ observations of marine life at depths where it, according to common belief at that time, should be non-existent, induced other nations to make provisions for expedition cruises to explore the oceans.
The Michael Sars Expedition 1910
The steam ship Michael Sars was an important precondition for the Atlantic Ocean cruise, and it was equipped with the most outstanding technology available at the time to investigate great depths.
Length: 38 metres
Tonnage: 226 tons
Engine: steam (5 ton coal per day and night)
Power Engine: 300 hps (about 225 kW)
Speed: 10 knots
More than one hundred new species
A group of international scientists participated in the finishing off of the material gathered in the deep sea by the Michael Sars Expedition in 1910. The description of more than a hundred new species was the outcome of this four-month long cruise.
Hjort and Murray both got unknown octopuses named after them:
• Cirrothauma murrayi (left) lives in the dark at depths ranging from 1 500 to 4 500 metres.
It has very small eyes, and lacks lenses. It does not possess object recognition like other types of octopuses.
• Mastigoteuthis hjorthi has thousands of tiny suction cups on its long tentacles. Underwater video recordings have recently shown it hovering slanted over the sea-bed while feeding, using its tentacles to ”vacuumclean” for copepods and other small creatures.
•This fish, the Saccopharynx hjorti, is the only known specimen, deposited in the collections of Bergen Museum. Since the Michael Sars Expedition in 1910 no refinds have been recorded. S.hjorti is therefore a good example of the fact that we have only minimal knowledge of the biology and way of life of quite a few of the animal species on earth.
• Scopelarchus michaelsarsi was not described until after the Michael Sars Expedition, but has later been observed in the Pacific and the Indian Oceans. Adult individuals are both males and females (synchronous hermaphrodites), so that two fish may mutually fertilise the partner’s eggs.