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1 ^ - 1 ^ - ~ al PLATE 1 Photo of ~~sosbc4~s ~~so~t commonly known as the Antarchc too~- hsh. This species is an example of Notothenioid Hat has evolved neutral buoy- ancy Trough reduction of skeletal minerahzation and increased lipid deposition. SOURCE: Photo taken by Kevin HoeCing and provided courtesy of Dr. Chris Chant Universe of IHinois at U~ana-Champaign.

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PLATE 2 The icefish Chaenocephalus aceratus. (Left) An adult male of -45-cm total length. The background grid measures 10 x 10 cm. (Right) A living, gravid female. Lifting the operculum reveals the white complexion of the gills due to the absence of red blood cells. In red-blooded relatives, such as Notothenia corliceps (not shown), the gills are a brilliant crimson due to oxygenation of hemoglobin in red cells. SOURCE: Photos by H.W. Detrich, III. PLATE 3 Globin-related sequences in the genomes of red- and white-blooded Antarctic fishes. (A and B) Southern blots of genomic DNAs from four red- blooded fishes: Gg, the Antarctic humped rocked (Gobionotothen gibberifrons); Na, the New Zealand black cod (Notothenia angustata); Nc, the Antarctic yellowbelly rockcod ( OCR for page 167
A B ~ - GLOBIN ~ - GLOBIN G~ ~< ~ G~ &~ O~ ~ 9~ ~ G~ & The Adult GIobin Gene Complex of Antarctic Fishes Notothen~a coraceps, a red-blooded notothenioid cc-.lobin ,, 13-.lobin ~_~ 39 - 5, ~' ~ 3, Icefishes, the ~hite-blooded notothenioids a ~ I d I Typical a-globin gelle remnant (14 of 16 species) ac ~ ~ ~. /~. ~a~ c - ,~l~l ,o, .veopag ~opsis ~ on a~ a Splice defect ,~ ~ilo Dacodraco hunteri I I I I I I I I I D ~ I i I ~ i I ~ O.5 ~ ~ 1.5 2.8 4.5 5.O 5.5 S.~b gene only, and the 16th species, Dacodraco hunteri, has a further deletion in the alpha-globin gene remnant. These data imply that globin gene loss occurred a minimum of three times during diversification of the hemoglobinless icefishes. SOURCE: A and B. Cocca et al., 1995; C, H.W. Detrich, III unpublished results. 3 1

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~~ ~ S~L.F ~ ~~; ~ PLATE 4 Map showing the latitudinal and sea-land gradients along the Victoria Land coast being studied by the Italian and New Zealand research programs. Red spots indicate sites of possible sample collection. SOURCE: Berkman and Tipton-Everett, 2001. 1

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10 ,U~L PLATE 5 (A) Photographic presentation of an aggregate from 2 m beneath the surface of the permanent ice cover of Lake Bonney located in the upper Taylor Valley of the McMurdo Dry Valley system. The photograph was taken from within a 3.5-m deep trench cut into the ice in early September before the forma- tion of liquid water. (B) Computed tomography (CT) scan of a section of ice core from Lake Vida, Victoria Valley (blue = ice, black spheres within the core section = gas bubbles in the ice, red-orange = sediment particles, green = particulate organic matter). The inner diameter of the circular sample chamber (blue-green ring) surrounding the ice core section is 76 mm. (C) Confocal laser photomicro- graphs showing microorganisms associated with a sediment particle with enlarged views of two species of cyanobacteria (blue = DAPI stained bacteria, red = chloro- phyll autofluorescence, gray = sediment particle). (D) SCOT microautoradio- graph of sediment particles bound together by cyanobacterial filaments (dark regions denote sites of active i4C accumulation indicative of photosynthetic activ- ity). NOTE: DAPI = 4',6-diamidino-2-phenylindole, dihydrochloride. SOURCE: Modified from Priscu et al., 1998.

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| LAKE ICE MICROBIAL CONSORTIUM | Photosynthetic prokaryotes l E:: f oc t_ A I CO, NH + 51 4 ~ 14--' . ~ I Heterotrophic prokaryotes l Close spatial arrangement on lithic surface PLATE 6 Consortial relationships between photosynthetic and heterotrophic prokaryotes found within the ice covers of the McMurdo Dry Valley lakes. NOTE: IAS = ice active substances. N2 indicates that both groups of prokaryotes fix atmospheric nitrogen that is exchanged between them. All of these exchanges take place on micron or smaller scales. Such a consortium is necessary for the survival and proliferation of life in the extreme environment posed by permanent Antarctic lake ice. SOURCE: Priscu et al., in press.

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~ f i/ /\ PLATE 7 Map of the major facilities supporting research in the Arctic. 1

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