LIPID SACS AS A BUOYANCY ADAPTATION IN AN ANTARCTIC FISH
LIPID SACS AS A BUOYANCY ADAPTATION IN AN ANTARCTIC FISH
复制标题
DOI：
10.1038/271352a0
复制
发表时间：
1978-01-01
期刊：
影响因子：
64.8
通讯作者：
EASTMAN, JT
中科院分区：
文献类型：
--
作者：
DEVRIES, AL;EASTMAN, JT
Notothenioidei是南极主要的波斯亚目鱼类，主要是底栖鱼类，约有75种1。它们没有鱼囊，这一特征与它们在海底的生活方式一致。因此，很少有人能够利用南极海洋2、3中层水域本土的浮游甲壳类(磷虾)的巨大生物量。然而，一个值得注意的例外是北极光甲藻入侵了这一高生产力的栖息地。与这个家族的其他成员不同，Pleuragrammas希望在水中游泳2，4，有时在海冰的覆盖下。尽管Pleuragramma有一个鱼囊，但人们观察到，当它被放置在水族箱中时，它在水中几乎一动不动。此外，其缓慢的游泳速度和一般的身体形态(图1)似乎排除了使用向前运动和相关的流体动力升力作为在水柱中保持位置的机制。在-1.8°C的海水中，Pleuragram的样品在空气中的重量在0.5%到1%之间，这表明它们几乎是中性浮力。我们在此报告，这种密度的降低是由于肌肉间和皮下囊中脂肪的积累，以及骨骼骨化的减少。
THE Notothenioidei, the dominant perciform suborder of Antarctic fishes, is a predominantly benthic group of about 75 species1. They lack a swim bladder, a feature consistent with their mode of life on the bottom of the sea1. Therefore few of them have been able to exploit the enormous biomass of planktonic crustaceans (krill) indigenous to the mid-waters of the Antarctic Ocean2,3. One notable exception, however, is the nototheniidPleuragramma antarcticumBoulenger which has invaded this highly productive habitat. Unlike other members of this family,Pleuragrammaspends its life swimming in the water2,4, at times beneath a cover of sea ice. AlthoughPleuragrammalacks a swim bladder, it has been observed to remain nearly motionless in the water when placed in an aquarium. Furthermore, its slow swimming speed and general body morphology (Fig. 1) appear to preclude the use of forward motion and associated hydrodynamic lift as a mechanism for maintaining position in the water column. In—1.8 °C seawater, specimens ofPleuragrammaweighed between 0.5 and 1 % of their weight in air indicating they were almost neutrally buoyant. We report here that this reduction in density results from the accumulation of lipid in intermuscular and subcutaneous sacs, and from a reduction in skeletal ossification.