Marine habitats
Bathymetric showing part of Davidson Seamount. The dots indicate significant coral nurseries.
	Littoral zone
	Intertidal zone
	Estuaries
	Kelp forests
	Coral reefs
	Ocean banks
	Continental shelf
	Neritic zone
	Straits
	Pelagic zone
	Oceanic zone
	Seamounts
	Hydrothermal vents
	Cold seeps
	Demersal zone
	Benthic zone
v t e

A seamount is a mountain rising from the ocean seafloor that does not reach to the water's surface (sea level), and thus is not an island. These are typically formed from extinct volcanoes, that rise abruptly and are usually found rising from the seafloor to 1,000-4,000 metres (3,000-13,000 ft) in height. They are defined by oceanographers as independent features that rise to at least 1,000 metres (3,281 ft) above the seafloor. The peaks are often found hundreds to thousands of metres below the surface, and are therefore considered to be within the deep sea.^[1] There are an estimated 100,000 seamounts across the globe, with only a few having been studied. Seamounts come in all shapes and sizes, and follow a distinctive pattern of growth, activity, and death. In recent years, several active seamounts have been observed, for example Loihi in the Hawaiian Islands.

Because of their abundance, seamounts are one of the most common oceanic ecosystems in the world. Interactions between seamounts and underwater currents, as well as their elevated position in the water, attract plankton, corals, fish, and marine mammals alike. Their aggregational effect has been noted by the commercial fishing industry, and many seamounts support extensive fisheries. There are ongoing concerns on the negative impact of fishing on seamount ecosystems, and well-documented cases of stock decline, for example with the orange roughy (Hoplostethus atlanticus). 95% of ecological damage is done by bottom trawling, which literally scrapes whole ecosystems off seamounts.

Because of their large numbers, many seamounts remain to be properly studied, and even mapped. Bathymetry and satellite altimetry are two technologies working to close the gap. There have been instances where naval vessels have collided with uncharted seamounts; for example, Muirfield Seamount is named after the ship that struck it in 1973. However, the greatest danger from seamounts are flank collapses; as they get older, extrusions seeping in the seamounts put pressure on their sides, causing landslides that have the potential to generate massive tsunamis.

Geography[link]

Seamounts can be found in every ocean basin in the world, distributed extremely widely both in space and in age. A seamount is technically defined as an isolated elevational rising of 1,000 m (3,281 ft) or more from the surrounding seafloor, and with a limited summit area,^[2] a definition drafted in 1964. This definition is no longer strictly adhered to however, and some scientists recognize features as short as 100 m (328 ft) as seamounts. Under the strictest definition there are up to 100,000 seamounts in the oceans, and under the loosest there may be as many as 2 million;^[3] however, there are many very small and very deep seamounts that are difficult to analyze, so the true number may never be known.^[2]

Most seamounts are volcanic in origin, and thus tend to be found on oceanic crust near mid-ocean ridges, mantle plumes, and island arcs. Nearly half of the world's seamounts are found in the Pacific Ocean, and the rest are distributed mostly across the Atlantic and Indian oceans. Overall there is also a significant bias in distribution towards the southern hemisphere.^[2]

Seamounts are often found in groupings or submerged archipelagos, a classic example being the Emperor Seamounts, an extension of the Hawaiian Islands. Formed millions of years ago by volcanism, they have since subsided far below sea level. This long chain of islands and seamounts extends thousands of kilometers northwest from the island of Hawaii. Isolated seamounts and those without clear volcanic origins are less common; examples include Bollons Seamount, Eratosthenes Seamount, Axial Seamount and Gorringe Ridge.^[4] If all known seamounts were collected into one area, they would make a landform the size of Europe.^[5] Their overall abundance makes them one of the most common, and least understood, marine structures and biomes on Earth,^[6] a sort of exploratory frontier.^[7]

A partial mapping of some of the world's major seamounts

Geology[link]

Geochemistry and evolution[link]

Diagram of a submarine eruption. (key: 1. Water vapor cloud 2. Water 3. Stratum 4. Lava flow 5. Magma conduit 6. Magma chamber 7. Dike 8. Pillow lava) Click to enlarge.

Most seamounts are built by one of two volcanic processes, although some, such as the Christmas Island Seamount Province near Australia, are more enigmatic.^[8] Volcanoes near plate boundaries and mid-ocean ridges are built by decompression melting of rock in the mantle that then floats up to the surface, while volcanoes formed near subducting zones are created because the subducting plate adds volatiles to the rising plate that raise its melting point. Which process formed the seamount has a profound effect on its eruptive materials. Lava flows from mid-ocean ridge and plate boundary seamounts are mostly basaltic (both tholeiitic and alkalic), whereas flows from subducting ridge volcanoes are mostly calc-alkaline lavas. Compared to mid-ocean ridge seamounts, subduction zone seamounts generally have more sodium, alkali, and volatile abundances, and less magnesium, resulting in more explosive, viscous eruptions.^[7]

All volcanic seamounts follow a particular pattern of growth, activity, subsidence and eventual extinction. The first stage of a seamount's evolution is its early activity, building its flanks and core up from the sea floor. This is followed by a period of intense volcanism, during which the new volcano erupts almost all (e.g. 98%) of its total magmatic volume. The seamount may even grow above sea level to become an oceanic island (for example, the 2009 eruption of Hunga Tonga). After a period of explosive activity near the ocean surface, the eruptions slowly die away. With eruptions becoming infrequent and the seamount losing its ability to maintain itself, the volcano starts to erode. After finally becoming extinct (possibly after a brief rejuvenated period), they are ground back down by the waves. Seamounts are built in a far more dynamic oceanic setting then their land counterparts, resulting in horizontal subsidation as the seamount moves on the grinding plate towards a subduction zone. Here it is subducted under the plate margin and ultimately destroyed, but it may leave evidence of its passage by carving an indentation into the opposing wall of the subduction trench. The majority of seamounts have already completed their eruptive cycle, so access to early flows by researchers is limited by late volcanic activity.^[7]

Ocean-ridge volcanoes in particular have been observed to follow a certain pattern in terms of eruptive activity, first observed with Hawaiian seamounts but now shown to be the process followed by all seamounts of the ocean-ridge type. During the first stage the volcano erupts basalt of various types, caused by various degrees of mantle melting. In the second, most active stage of its life, ocean-ridge volcanoes erupt tholeiitic to mildly alkalic basalt as a result of a larger area melting in the mantle. This is finally capped by alkalic flows late in its eruptive history, as the link between the seamount and its source of volcanism is cut by crustal movement. Some seamounts also experience a brief "rejuvenated" period after a hiatus of 1.5 to 10 million years, the flows of which are highly alkalic and produce many xenoliths.^[7]

In recent years, geologists have confirmed that a number of seamounts are active undersea volcanoes; two examples are Lo‘ihi in the Hawaiian Islands and Vailulu'u in the Manu'a Group (Samoa).^[4]

Lava types[link]

Pillow lava, a type of basalt flow that originates from lava-water interactions during submarine eruptions.^[9]

The most apparent lava flows at a seamount are the eruptive flows which cover their flanks, however igneous intrusions, in the forms of dikes and sills, are also an important part of seamount growth. The most common type of flow is pillow lava, named so after its unusual shape. Less common are sheet flows, which are glassy and marginal, and indicative of larger-scale flows. Volcaniclastic sedimentary rocks dominate shallow-water seamounts. They are the products of the explosive activity of seamounts that are near the water's surface, and can also form from mechanical wear of existing volcanic rock.^[7]

Structure[link]

Seamounts can form in a wide variety of tectonic settings, resulting in a very diverse structural bank. Seamounts come in a wide variety of structural shapes, from conical to flat-topped to complexly shaped.^[7] Some are built very large and very low, such as Koko Guyot^[10] and Detroit Seamount;^[11] others are built more steeply, such as Loihi Seamount^[12] and Bowie Seamount.^[13] Some seamounts also have a carbonate or sediment cap.^[7]

Many seamounts show signs of intrusive activity, which is likely to lead to inflation, steepening of volcanic slopes, and ultimately, flank collapse.^[7] There are also several sub-classes of seamounts. The first are guyots, seamounts with a flat top. These tops must be 200 m (656 ft) or more below the surface of the sea; the diameters of these flat summits can be over 10 km (6.2 mi).^[14] Knolls are isolated elevation spikes measuring less than 1,000 meters (3,281 ft). Lastly, pinnacles are small pillar-like seamounts.^[2]

Ecology[link]

Ecological role of seamounts[link]

Seamounts are exceptionally important to their biome ecologically, but their role in their environment is little understood. Because they project out above the surrounding sea floor, they disturb standard water flow, causing eddies and associated hydrological phenomena that ultimately result in water movement in an otherwise still ocean bottom. Currents have been measured at up to 0.9 knots, or 48 centimeters per second. Because of this upwelling seamounts often carry above-average plankton populations, seamounts are thus centers where the fish that feed on them aggregate, in turn falling prey to further predation, making seamounts important biological hotspots.^[2]

Seamounts provide habitats and spawning grounds for these larger animals, including numerous fish. Some species, including black oreo (Allocyttus niger) and blackstripe cardinalfish (Apogon nigrofasciatus), have been shown to occur more often on seamounts than anywhere else on the ocean floor. Marine mammals, sharks, tuna, and cephalopods all congregate over seamounts to feed, as well as some species of seabirds when the features are particularly shallow.^[2]

Grenadier fish (Coryphaenoides sp.) and bubblegum coral (Paragorgia arborea) on the crest of Davidson Seamount. These are two species attracted to the seamount; Paragorgia arborea in particular grows in the surrounding area as well, but nowhere near as profusely.^[15]

Seamounts often project upwards into shallower zones more hospitable to sea life, providing habitats for marine species that are not found on or around the surrounding deeper ocean bottom. Because seamounts are isolated from each other they form "undersea islands" creating the same biogeographical interest. As they are formed from volcanic rock, the substrate is much harder than the surrounding sedimentary deep sea floor. This causes a different type of fauna to exist than on the seafloor, and leads to a theoretically higher degree of endemism.^[16] However, recent research especially centered at Davidson Seamount suggests that seamounts may not be especially endemic, and discussions are ongoing on the effect of seamounts on endemicity. They have, however, been confidently shown to provide a habitat to species that have difficulty surviving elsewhere.^[17][18]

The volcanic rocks on the slopes of seamounts are heavily populated by suspension feeders, particularly corals, which capitalize on the strong currents around the seamount to supply them with food. This is in sharp contrast with the typical deep-sea habitat, where deposit-feeding animals rely on food they get off the ground.^[2] In tropical zones extensive coral growth results in the formation of coral atolls late in the seamount's life.^[3][18]

In addition soft sediments tend to accumulate on seamounts, which are typically populated by polychaetes (annelid marine worms) oligochaetes (microdrile worms), and gastropod mollusks (sea slug^{[disambiguation needed ]}s). Xenophyophores have also been found. They tend to gather small particulates and thus form beds, which alters sediment deposition and creates a habitat for smaller animals.^[2] Many seamounts also have hydrothermal vent communities, for example Suiyo^[19] and Loihi seamounts.^[20] This is helped by geochemical exchange between the seamounts and the ocean water.^[7]

Seamounts may thus be vital stopping points for some migratory animals, specifically whales. Some recent research indicates whales may use such features as navigational aids throughout their migration.^[21] For a long time it has been surmised that many pelagic animals visit seamounts as well, to gather food, but proof of this aggregating effect has been lacking. The first demonstration of this conjecture was published in 2008.^[22]

Fishing[link]

The effect that seamounts have on fish populations has not gone unnoticed by the commercial fishing industry. Seamounts were first extensively fished in the second half of the 20th century, due to poor management practices and increased fishing pressure seriously depleting stock numbers on the typical fishing ground, the continental shelf. Seamounts have been the site of targeted fishing since that time.^[23]

Nearly 80 species of fish and shellfish are commercially harvested from seamounts, including spiny lobster (Palinuridae), mackerel (Scombridae and others), red king crab (Paralithodes camtschaticus), red snapper (Lutjanus campechanus), tuna (Scombridae), Orange roughy (Hoplostethus atlanticus), and perch (Percidae).^[2]

Conservation[link]

Because of overfishing at their seamount spawning grounds, stocks of orange roughy (Hoplostethus atlanticus) have plummeted; experts say that it could take decades for the species to restore itself to its former numbers.^[23]

The ecological conservation of seamounts is hurt by the simple lack of information available. Seamounts are very poorly studied, with only 350 of the estimated 100,000 seamounts in the world having received sampling, and fewer than 100 in depth.^[24] Much of this lack of information can be attributed to a lack of technology, and to the daunting task of reaching these underwater structures; the technology to fully explore them has only been around the last few decades. Before consistent conservation efforts can begin, the seamounts of the world must first be mapped, a task that is still in progress.^[2]

Overfishing is a serious threat to seamount ecological welfare. There are several well-documented cases of fishery exploitation, for example the orange roughy (Hoplostethus atlanticus) off the coasts of Australia and New Zealand and the pelagic armorhead (Pseudopentaceros richardsoni) near Japan and Russia.^[2] The reason for this is that the fishes that are targeted over seamounts are typically long-lived, slow-growing, and slow-maturing. The problem is confounded by the dangers of trawling, which damages seamount surface communities, and the fact that many seamounts are located in international waters, making proper monitoring difficult.^[23] Bottom trawling in particular is extremely devastating to seamount ecology, and is responsible for as much as 95% of ecological damage to seamounts.^[25]

Coral earings of this type are often made from coral harvested off seamounts.

Corals from seamounts are also vulnerable, as they are highly valued for making jewellery and decorative objects. Significant harvests have been produced from seamounts, often leaving coral beds depleted.^[2]

Individual nations are beginning to note the effect of fishing on seamounts, and the European Commission has agreed to fund the OASIS project, a detailed study of the effects of fishing on seamount communities in the North Atlantic.^[23] Another project working towards conservation is CenSeam, a Census of Marine Life project formed in 2005. CenSeam is intended to provide the framework needed to prioritise, integrate, expand and facilitate seamount research efforts in order to significantly reduce the unknown and build towards a global understanding of seamount ecosystems, and the roles they have in the biogeography, biodiversity, productivity and evolution of marine organisms.^[24][26]

Possibly the best ecologically studied seamount in the world is Davidson Seamount, with six major expeditions recording over 60,000 species observations. The contrast between the seamount and the surrounding area was well-marked.^[17] One of the primary ecological havens on the seamount is its deep sea coral garden, and many of the specimens noted were over a century old.^[15] Following the expansion of knowledge on the seamount there was extensive support to make it a marine sanctuary, a motion that was granted in 2008 as part of the Monterey Bay National Marine Sanctuary.^[27] Much of what is known about seamounts ecologically is based on observations from Davidson.^[15][22] Another such seamount is Bowie Seamount, which has also been declared a marine protected area by Canada for its ecological richness.^[28]

Exploration[link]

The study of seamounts has been stymied for a long time by the lack of technology. Although seamounts have been sampled as far back as the 19th century, their depth and position meant that the technology to explore and sample seamounts in sufficient detail did not exist until the last few decades. Even with the right technology available, only a scant 1% of the total number have been explored,^[5] and sampling and information remains biased towards the top 500 m (1,640 ft).^[2] New species are observed or collected and valuable information is obtained on almost every submersible dive at seamounts.^[6]

Before seamounts and their oceanographic impact can be fully understood, they must be mapped, a daunting task due to their sheer number.^[2] The most detailed seamount mappings are provided by multibeam echosounding (sonar), however after more than 5000 publicly held cruises, the amount of the sea floor that has been mapped remains minuscule. Satellite altimetry is a broader alternative, albeit not as detailed, with 13,000 catalogued seamounts; however this is still only a fraction of the total 100,000. The reason for this is that uncertainties in the technology limit recognition to features 1,500 m (4,921 ft) or larger. In the future, technological advances could allow for a larger and more detailed catalogue.^[3]

Deep-sea mining[link]

Seamounts are a possible future source of heavy metals. The growth of the human population and, with it, heavy industry, has pressed demands for Earth's finite resources. Even though the ocean makes up 70% of the world, technological challenges with deep-sea mineral mining have severely limited its extent. But with the constantly decreasing supply on land, many see oceanic mining as the destined future, and seamounts stand out as candidates.^[29]

Seamounts are abundant, and all have metal resource potential because of various enrichment processes during the seamount's life. Hydrogenic Iron-manganese, hydrothermal iron oxide, sulfide, sulfate, sulfur, hydrothermal manganese oxide, and phosphorite^[30] (the latter especially in parts of Micronesia) are all mineral resources that are founded by various processes and deposited upon seamounts. However, only the first two have any potential of being targeted by mining in the next few decades.^[29]

Dangers[link]

USS San Francisco in dry dock in Guam in January 2005, following its collision with an uncharted seamount. The damage was extensive and the submarine was just barely salvaged.^[31]

Some seamounts have not been mapped and thus pose a navigational danger. For instance, Muirfield Seamount is named after the ship that hit it in 1973.^[32] More recently, the submarine USS San Francisco ran into an uncharted seamount in 2005 at a speed of 35 knots (40.3 mph; 64.8 km/h), sustaining serious damage and killing one seaman.^[31]

One major seamount risk is that often, in the late of stages of their life, extrusions begin to seep in the seamount. This activity leads to inflation, over-extension of the volcano's flanks, and ultimetly flank collapse, leading to submarine landslides with the potential to start major tsunamis. This is one of the largest natural disasters in the world. In an illustration of the potent power of flank collapses, a summit collapse on the northern edge of Vlinder Seamount resulted in a pronounced headwall scarp and a field of debris up to 6 km (4 mi) away.^[7] A catastrophic collapse at Detroit Seamount flattened its whole structure extensively.^[11] Lastly, in 2004, scientists found marine fossils 61 m (200 ft) up the flank of Kohala mountain in Hawaii (island). Subsidation analysis found that at the time of their deposition, this would have been 500 m (1,640 ft) up the flank of the volcano,^[33] far too high for a normal wave to reach. The date corresponded with a massive flank collapse at the nearby Mauna Loa, and it was theorized that it was a massive tsunami, generated by the landslide, that deposited the fossils.^[34]

See also[link]

• Ocean trench

References[link]

Bibliography[link]

Geology

• Keating, B.H., Fryer, P., Batiza, R., Boehlert, G.W. (Eds.), 1987: Seamounts, islands and atolls. Geophys. Monogr. 43:319-334.
• Menard, H.W. (1964). Marine Geology of the Pacific. International Series in the Earth Sciences. McGraw-Hill, New York, 271 pp.

Ecology

• De Forges, BR; Richer de Forges, J. Anthony Koslow, and G. C. B. Poore (22 June 2000). "Diversity and endemism of the benthic seamount fauna in the southwest Pacific". Nature (Nature Publishing Group) 405 (6789): 944–947. DOI:10.1038/35016066. PMID 10879534. http://www.nature.com/nature/journal/v405/n6789/full/405944a0.html. 
• Koslow, J.A. (1997). Seamounts and the ecology of deep-sea fisheries. Am. Sci. 85:168-176.
• Lundsten L, McClain CR, Barry JP, Cailliet GM, Clague DA, DeVogelaere AP (2009) Ichthyofauna on Three Seamounts off Southern and Central California, USA. Marine Ecology Progress Series 389:223-232.
• Pitcher, T.J., Morato, T., Hart, P.J.B., Clark, M.R., Haggan, N. and Santos, R.S. (eds) (2007). "Seamounts: Ecology, Fisheries and Conservation". Fish and Aquatic Resources Series 12, Blackwell, Oxford, UK. 527pp. ISBN 978-1-4051-3343-2

External links[link]

Geography and geology

• Earthref Seamount Catalogue. A database of seamount maps and catalogue listings.
• Volcanic History of Seamounts in the Gulf of Alaska.
• The giant Ruatoria debris avalanche on the northern Hikurangi margin, New Zealand. Aftermath of a seamount carving into the far side of a subduction trench.
• Evolution of Hawaiian volcanoes. The life cycle of seamounts was originally observed off of the Hawaiian arc.
• How Volcanoes Work: Lava and Water. An explanation of the different types of lava-water interactions.

Ecology

• A review of the effects of seamounts on biological processes. NOAA paper.
• Mountains in the Sea, a volume on the biological and geological effects of seamounts, available fully online.
• SeamountsOnline, seamount biology database.
• Vulnerability of deep sea corals to fishing on seamounts beyond areas of national jurisdiction, United Nations Environment Program.

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Felix Anton Dohrn
Born	(1840-09-29)September 29, 1840 Stettin (Szczecin), Pomerania
Died	September 26, 1909(1909-09-26) (aged 68)
Nationality	German
Fields	Biology

Felix Anton Dohrn (29 September 1840 - 26 September 1909) was a prominent German Darwinist and the founder and first director of the first zoological research station in the world, the Stazione Zoologica in Naples, Italy.

Family history[link]

Dohrn was born in Stettin (Szczecin), Pomerania, into a wealthy middle class family. His grandfather, Heinrich Dohrn, had been a wine and spice merchant, and had made the family fortune by trading in sugar. This wealth allowed Anton's father, Carl August, to devote himself to his various hobbies; travelling, folk music and insects. Anton, the youngest son, read zoology and medicine at various German universities (Königsberg, Bonn, Jena and Berlin). His brother Heinrich Wolfgang Ludwig Dohrn was also a zoologist.

In 1874 Dohrn married sixteen year old Marie de Baranowska who he had met in Messina. They had four children Boguslaw, Wolfgang, Harald und Reinhard.

• 

  Marie de Baranowska

• 

  The Dohrn family. Anton, Marie and their four sons Boguslaw, Wolfgang, Harald und Reinhard.

Entomology[link]

Dohrn was initially interested in Hemiptera.In 1859 published Beitrag zur Kennitss der Harpactoridae in Entomologische Zeitung and the more important Catalogus hemipterorum. Entomologischer Vereinin Stettin, Buchdruckerei von Herrcke & Lebeling, Stettin.He gained his doctorate from Breslau in November 1865 with his thesis “On the Anatomy of Hemiptera". At this time was associated with the English scientific establishment through his fathers friendship with Henry Tibbats Stainton.

Introduction to Darwinism[link]

Anton Dohrn and other naturalists in Heligoland

His ideas changed in summer 1862 when he returned to study at Jena, where Ernst Haeckel introduced him to Darwin's work and theories. Dohrn became a fervent defender of Darwin's theory of evolution by natural selection.

At that time comparative embryology was the keystone of morphological evolutionary studies, based on Haeckel's recapitulation theory, the idea that an organism during its embryonic development passes through the major stages of the evolutionary past of its species. Morphology became one of the major ways in which zoologists sought to expand and develop Darwinian theory in the latter years of the 19th century. Dohrn chose to become a "Darwinian morphologist".

Dohrn received his doctorate in 1865 at Breslau under Eduard Grube, and his Habilitation in 1868 at Jena with Rudolf Virchow, Ernst Haeckel and Carl Gegenbaur. The study subjects were Medicine und Zoology and his Jena monograph was Studien zur Embryologie der Arthropoden. From 1868-1870 he was a Docent in zoology at Jena. During these times, he worked several times at facilities located by the sea: Heligoland alongside Haeckel in 1865, Hamburg in 1866, Millport, Scotland with David Robertson in 1867 and 1868 and moved to Messina, Italy, during the winter of 1868 together with his friend and colleague Nicholas Miklouho-Maclay to work on the marine life of the Straits of Messina. In 1870 Dohrn was called up to (briefly) serve in the Franco-Prussian War.

Development of "zoological stations"[link]

Work stations in the Naples laboratory in 1901

From 1850 to 1852 Dohrn lived in Nice where he tried unsuccessfully to enlist support for a marine zoological station (one was later established as Observatoire Oceanologique de Villefranche). In Messina, Dohrn and Miklouho-Maclay conceived a plan to cover the globe with a network of zoological research stations, analogous to railway stations, where scientists could stop, collect material, make observations and conduct experiments, before moving on to the next station.

Dohrn realised how useful it would be for scientists to arrive at a location and find a ready to use laboratory. Dohrn rented two rooms for the "Stazione Zoologica di Messina", but quickly realized the technical difficulties of studying marine life without a permanent structure and support facilities, such as trained personnel and a library.

Foundation of the Stazione Zoologica[link]

In 1870 Dohrn decided that Naples would be a better place for his Station. This choice was due to the greater biological richness of the Gulf of Naples and also to the possibility of starting a research institute of international importance in a large university town that itself had a strong international element.

After a visiting a newly opened aquarium in Berlin, the Berliner Aquarium Unter den Linden he decided that charging the general public to visit an aquarium might earn the laboratory enough money to pay a salary for a permanent assistant. Naples, with a population of 500,000 inhabitants, was one of the largest and most attractive cities of Europe and also had a considerable flow of tourists (30,000 a year) that could potentially visit the aquarium.

Dohrn overcame the doubts of the city authorities and persuaded them to give him, free-of-charge, a plot of land at the sea edge, in the beautiful Villa Comunale on the condition that he promised to build the Stazione Zoologica at his own expense.

He opened the station to visiting scientists in September 1873, and to the general public in January 1874.

In 1875 Dohrn published Der Ursprung der Wirbelthiere und das Princip des Functionswechsels: Genealogische Skizzen which proposed the "turn over" theory of the origin of vertebrates.

The "Bench" system[link]

In order to promote the international status of the Stazione and to guarantee its economic and hence political independence and freedom of research, Dohrn introduced a series of innovative measures to finance his project. Firstly, the rental of work and research space (the "Bench system"), for an annual fee universities, governments, scientific institutions, private foundations or individuals could send one scientist to the Stazione for one year where he or she would find available all that was required to conduct research (laboratory space, animal supply, chemicals, an exceptional library and expert staff). These facilities were supplied with no strings attached, in the sense that investigators were completely free to pursue their own projects and ideas.

This system worked extremely well, and when Anton Dohrn died in 1909 more than 2,200 scientists from Europe and the United States had worked at Naples and more than 50 tables-per-year had been rented out. It was in fact at Naples that international scientific collaboration in the modern sense was invented, based on quick and free communication of ideas, methods and results.

Legacy[link]

Map showing location of the Anton Dohrn Seamount

The success of the Stazione Zoologica, and the new way of thinking and funding research are the main legacies of Dohrn. The model was copied a number of times throughout the world. In 1878 Johns Hopkins University founded the Chesapeake Zoological Laboratory, under the direction of W.K. Brooks. Then, in 1888, the Marine Biological Laboratory was founded at Woods Hole and in 1892 the first laboratory on the west coast, the Hopkins Marine Station, opened in California. In Britain, current marine laboratories that originate from this time include the Dunstaffnage Marine Station (today Scottish Association for Marine Science, 1884), the Gatty Marine Laboratory (University of St Andrews, 1884), the Marine Biological Association of the United Kingdom (Plymouth, 1888), the Dove Marine Laboratory (Newcastle University, 1897), the Fisheries Research Services Marine Laboratory (Aberdeen, 1899), and the Bangor Marine Station (Queen's University of Belfast, 1903).

Dohrn's name has been immortalised in an undersea feature, the Anton Dohrn Seamount, a seamount in the Rockall Trough, to the north-west of the British Isles, which has become known for the great biodiversity which lives on the cold-water coral, Lophelia pertusa, in this region.

A motorboat owned by the Carnegie Institute of Washington, D.C. named Anton Dohrn in the early 20th century served in the United States Navy as the patrol vessel USS Anton Dohrn (SP-1086) from 1917 to 1919.

References[link]

• Theodor Heuss (in German: 1940) Anton Dohrn in Neapel. Atlantis-Verlag, Berlin; Rainer Wunderlich, Tübingen 1948 and 1962 (Title now: "Anton Dohrn"); in English 1991, transl. by Liselotte Dieckmann, ed. Christiane Gröben Anton Dohrn. A Life for Science Springer, NY ISBN 0-387-53561-6 Springer, Berlin ISBN 3-540-53561-6
• Karl Ernst von Baer & Anton Dohrn Correspondence 1993. Ed. Christiane Gröben. Amer Philosophical Society ISBN 0-87169-833-1
• Theodor Boveri 2009: Anton Dohrn (1910) Kessinger ISBN 1-104-61706-4
• Musgrave, A. 1932 Bibliography of Australian Entomology 1775 - 1930. Sydney
• Semenov-Tjan-Schanskij, A. P. 1909 [Dohrn, F. A.] Revue Russe d'Entomologie 9

External links[link]

• Stazione Zoologica Anton Dohrn
• Short biography, bibliography,letters and links on digitized sources in the Virtual Laboratory of the Max Planck Institute for the History of Science Via Marine Station.Links to full text of Nunn, Emily. 1883. The Naples Zoological Station, I & II. Science 1: 479-481, 507-510
• Anton Dohrn Café Blog
• DEI ZALF Biographies of Entomologists of the World.
• Stazione Zoologica and the development of embryology
• Groeben
• Darwin Project. Letters to Charles Darwin
• Embryology