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Assignments: Nomenclature, Latin and Greek Vasquez et al. Etmopterus benchleyi , a new lanternshark - and a note on sources, referencing, and plagiarism. The Aquatic Environment - a brief overview. Tell me about this environment, and what it conveys about its inhabitants ….
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Assignments: Nomenclature, Latin and Greek Vasquez et al. Etmopterus benchleyi, a new lanternshark - and a note on sources, referencing, and plagiarism
The Aquatic Environment - a brief overview
Tell me about this environment, and what it conveys about its inhabitants….
Tell me about this fish, and what it conveys about its environment….
Aquatic environment • salinity – from 0 to 70 ppt Fresh water = 0-2 ppt Brackish (estuarine) = 2-30 ppt Salt water = 35 ppt • in fresh water, fish must resist osmotic intake of water • in salt water, fish must retain water and excrete salts
Aquatic environment • salinity – from 0 to 70 ppt • temperature - < 0 to > 30 C • water has high heat absorbance, 4 x that of air • fish are metabolically adapted to different temperature ranges; few are widely eurythermal • a few fish are adapted to temperatures below freezing
Aquatic environment • salinity – from 0 to 70 ppt • temperature - < 0 to > 30 C • motion – stagnant to torrents • various morphological adaptations to moving water
Aquatic environment • salinity – from 0 to 70 ppt • temperature - < 0 to > 30 C • motion – stagnant to torrents • dissolved materials - gases, solids • oxygen in water relatively unavailable, compared to air • methods to acquire oxygen are varied • too little oxygen >> air breathing • too much oxygen >> gas supersaturation problems
Aquatic environment • salinity – from 0 to 70 ppt • temperature - < 0 to > 30 C • motion – stagnant to torrents • dissolved materials - gases, solids • pressure – deepest water is 11,000 m (6.9 miles, 11 km) • pressure increases 1 atm for every 33’ (10 m) of depth • to maintain buoyancy, fish must compensate • skeletal structure of deep sea fish is reduced due to support by water
Aquatic environment • salinity – from 0 to 70 ppt • temperature - < 0 to > 30 C • motion – stagnant to torrents • dissolved materials - gases, solids • pressure – deepest water is 11,100 m (6.9 miles, 11 km) • viscosity – water is 800x more dense than air • requires much more effort to move through water than air • streamlining is critical; max. speed (tuna) is ~ 21 m/sec
Aquatic environment • salinity – from 0 to 70 ppt • temperature - < 0 to > 30 C • motion – stagnant to torrents • dissolved materials - gases, solids • pressure – deepest water is 11,100 m (6.9 miles, 11 km) • viscosity • light - attenuates with depth, turbidity • many fishes adapted to zero light conditions • some fishes generate their own light • issues for color
Aquatic environment • salinity – from 0 to 70 ppt • temperature - < 0 to > 30 C • motion – stagnant to torrents • dissolved materials - gases, solids • pressure – deepest water is 11,100 m (6.9 miles, 11 km) • viscosity • light • sound - travels 4 x faster in water than air • directionality is difficult to achieve
Aquatic environments mean extreme area volume depth depth fresh 1% 0.01% few 1,600 m meters (Baikal) salt 70% 97% 3,790 m 11,000 m (trenches)
Habitat suitability Ontogenetic Cyclic Resident migrant migrant High for all functions all of the time Varies with size, age, or development High for one function, low for another function seasonal tidal diel Adapted from Able and Fahey 2010