ANTAROTIO BENTHOS
3
regions such as South America, New Zealand and Australia. It surely
warrants treatment as a unit on its own. At the same time the approach
to the Antarctic Region has been essentially faunal and the extensions
of the Antarctic fauna have been traced whenever necessary. Some
authors have not made a clear distinction between Antarctic and Subantarctic, and in reviewing their results the geographical scope may
have been extended.
Parasitic forms have not been treated in detail unless the occurrences
are of biogeographical interest.
11. THE ANTARCTIC ENVIRONMENT
In complete contrast to Arctic conditions, Antarctica consists of a
large land mass invested with ice sheets of varying thickness, and surrounded by a great body of water, the Southern Ocean (Herdman et d,
1966). Extending southwards into the Southern Ocean towards Antarctica are three spearheads of land, each a potential pathway whereby
organisms living on the shelves associated with three major landmasses could disperse, or have dispersed, southwards. From South
America, the Scotia Arc with its surface features of the Falklands,
South Georgia, the South Sandwich and South Orkney Islands and the
South Shetlands, curves towards the most northerly extension of the
Antarctic Continent, the Antarctic Peninsula.
New Zealand and Australia provide a more fragmented pathway
from Asia through the Indo-Malayan Archipelago. South Africa stops
at a greater distance from the Antarctic Continent but provides shallow
water contacts northwards into the Indian Ocean on one coast and into
the Atlantic on the other.
Deeper water organisms are brought closer into contact with Antarctic waters, the Southern Ocean being but a continuation of the
Pacific, Indian and Atlantic Oceans. There is no shortage of potential
migration routes through which biogeographers can derive the Antarctio
biota, or through which it may be considered to disperse. The biogeographer must try to deduce the routes that have actually been used
by the plants and animals concerned.
There have been many recent general accounts of the physical
oceanography of Antarctic and Subantarctic waters, some with a biological slant, (Deacon, 1937, 1960; Mackintosh, 1946, 1960; Knox,
1960 ; Ostapoff, 1965 ; Brodie, 1965 ; El-Sayed, 1968).
The biological significance of the water current patterns in the
Antarctic has been discussed by El-Sayed (1968) based on Deacon
(1937). The surface manifestations of Antarctic Surface Water near the
continent surrounded by a belt of Subantarctic Surface Water separated
3
regions such as South America, New Zealand and Australia. It surely
warrants treatment as a unit on its own. At the same time the approach
to the Antarctic Region has been essentially faunal and the extensions
of the Antarctic fauna have been traced whenever necessary. Some
authors have not made a clear distinction between Antarctic and Subantarctic, and in reviewing their results the geographical scope may
have been extended.
Parasitic forms have not been treated in detail unless the occurrences
are of biogeographical interest.
11. THE ANTARCTIC ENVIRONMENT
In complete contrast to Arctic conditions, Antarctica consists of a
large land mass invested with ice sheets of varying thickness, and surrounded by a great body of water, the Southern Ocean (Herdman et d,
1966). Extending southwards into the Southern Ocean towards Antarctica are three spearheads of land, each a potential pathway whereby
organisms living on the shelves associated with three major landmasses could disperse, or have dispersed, southwards. From South
America, the Scotia Arc with its surface features of the Falklands,
South Georgia, the South Sandwich and South Orkney Islands and the
South Shetlands, curves towards the most northerly extension of the
Antarctic Continent, the Antarctic Peninsula.
New Zealand and Australia provide a more fragmented pathway
from Asia through the Indo-Malayan Archipelago. South Africa stops
at a greater distance from the Antarctic Continent but provides shallow
water contacts northwards into the Indian Ocean on one coast and into
the Atlantic on the other.
Deeper water organisms are brought closer into contact with Antarctic waters, the Southern Ocean being but a continuation of the
Pacific, Indian and Atlantic Oceans. There is no shortage of potential
migration routes through which biogeographers can derive the Antarctio
biota, or through which it may be considered to disperse. The biogeographer must try to deduce the routes that have actually been used
by the plants and animals concerned.
There have been many recent general accounts of the physical
oceanography of Antarctic and Subantarctic waters, some with a biological slant, (Deacon, 1937, 1960; Mackintosh, 1946, 1960; Knox,
1960 ; Ostapoff, 1965 ; Brodie, 1965 ; El-Sayed, 1968).
The biological significance of the water current patterns in the
Antarctic has been discussed by El-Sayed (1968) based on Deacon
(1937). The surface manifestations of Antarctic Surface Water near the
continent surrounded by a belt of Subantarctic Surface Water separated