Data from: Southern Ocean mesopelagic fish comply with Bergmann's rule

The applicability of macroecological rules to patterns in body size varies between taxa. One of the most examined is Bergmann's rule, which states that body size increases with decreasing temperature and increasing latitude, although the rule is not universal and the proposed mechanisms underpinning it are multifarious and lack congruence. This study considers the degree to which Bergmann's rule applies to the Southern Ocean mesopelagic fish community. We studied patterns in body size, temperature and latitude across a 12° latitudinal gradient within the Scotia-Weddell sector. Intra-specific Bergmann's rule was found to apply to 8 out of the 11 biomass-dominant species in the family Myctophidae. The rule was also apparent at an inter-specific level. Our study suggests that greater attainable body size in this community is a necessary attribute to reach colder regions further south. The adherence of these taxa to Bergmann's rule enables such species to act as sentinels for identifying the drivers and consequences of ocean warming on the Southern Ocean ecosystem.

宏观生态学法则在体型分布格局中的适用性因分类群而异。其中受研究最为广泛的当属伯格曼法则（Bergmann's rule），该法则指出体型会随温度降低与纬度升高而增大，不过该法则并非普适性规律，其背后的潜在机制繁杂多样且缺乏共识。本研究探讨了伯格曼法则在南大洋中层鱼类群落中的适用程度。我们针对斯科舍-威德尔海域范围内12°纬度梯度下的体型、温度与纬度分布格局开展了研究。结果发现，在11种生物量占优的灯笼鱼科（Myctophidae）物种中，有8种符合种内伯格曼法则；该法则在种间水平上同样显著成立。本研究表明，该群落中物种的最大可达到体型，是抵达更南部寒冷海域的必要性状。这些类群对伯格曼法则的遵循性，使得这些物种可作为指示物，用以识别海洋变暖对南大洋生态系统的驱动因素与影响后果。