. Ecological animal geography; an authorized, rewritten edition based on Tiergeographie auf ockologischer grundlage . Fig. 65.—Deep-sea isopod, Eurycope novae-zelandiae, from 2000-m. depth, on blue ooze. After Beddard. very long limbs, the terminal joints of which are expanded by hairs to increase their supporting surface (Figs. 65-66). The abyssal pelagic community.—The upper limit of the lightless pelagial varies from 200 to 600 m. in depth according to the latitude. No sharp faunal division at this point is possible, especially as many of the inhabitants of the abyssal waters rise to the su
. Ecological animal geography; an authorized, rewritten edition based on Tiergeographie auf ockologischer grundlage . Fig. 65.—Deep-sea isopod, Eurycope novae-zelandiae, from 2000-m. depth, on blue ooze. After Beddard. very long limbs, the terminal joints of which are expanded by hairs to increase their supporting surface (Figs. 65-66). The abyssal pelagic community.—The upper limit of the lightless pelagial varies from 200 to 600 m. in depth according to the latitude. No sharp faunal division at this point is possible, especially as many of the inhabitants of the abyssal waters rise to the surface at night, while others undergo their development at the surface. There are forms which remain permanently in the abyssal waters; thus whereas 90% of the fish larvae and juvenile fishes collected by the Michael Sars in the Atlantic were caught in depths of 0-150 m., Alepocephalus appears to develop entirely below the lighted level. It is unusual for a surface animal to develop in the depths. The siphonophore Velella, whose larvae are taken at depths of 1000 m., is such an exception. Nocturnal net hauls on the surface frequently obtain fishes with every mark of the inhabitant of abyssal waters. In the herring fishery, the bottom trawl is used by day and surface nets at night. Cod caught
Size: 2314px × 2160px
Photo credit: © The Bookworm Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookcollectionbiodive, booksubjectanimalecology
