Spatial patterns in the body sizes of bird species in the New World
Spatial patterns in the body sizes of bird species in the New World
复制标题
DOI：
10.2307/3545933
复制
发表时间：
1996-12-01
期刊：
影响因子：
3.4
通讯作者：
Gaston, KJ
中科院分区：
文献类型：
--
作者：
Blackburn, TM;Gaston, KJ
动物体型的空间格局主要是为了评估伯格曼法则而研究的，伯格曼法则指出，体型与环境温度呈负相关，因此在密切相关的物种中，体型会随着纬度的增加而增加。然而，地理范围大小和物种丰富度也显示出空间变异，有证据表明，两者都与身体大小相关。令人惊讶的是，因此，一直没有尝试检查协变的身体大小，物种丰富度和地理范围大小模式，同时在一个单一的组合。在这里，我们这样做，使用新世界的鸟类组合。新世界鸟类的平均体重在赤道地区最低，并且随着赤道两侧的纬度增加而增加，正如伯格曼规则所预期的那样。然而，这种模式密切矿工，在物种丰富度，有一个很强的负相关性之间的物种数量在一个地区和他们的平均体重。这种相关性比任何一个变量与纬度的相关性都要强，并且暗示了一个共同的潜在原因。相比之下，一个地区物种的平均体长和平均地理分布区之间的关系很弱。然而，空间格局意味着，种间关系的范围大小和身体大小不同的纬度，这对保护评估的基础上物种的范围大小的重要后果。如果有一个生态学的原因，为什么更大的身体大小是在高纬度地区，那里的能源供应较低，这可以部分解释身体大小和物种丰富度的空间格局的巧合。范围大小的空间模式也可能部分地通过与身体大小的弱相关性来介导。因此，所有三个变量的空间模式可能是相互关联的。
Spatial patterns in animal body sizes have primarily been studied with the aim of evaluating Bergmann's rule, which states that body size is inversely related to ambient temperature, and hence increases with latitude across closely related species. However, geographic range sizes and species richness also show spatial variation, and there is evidence that both are correlated with body size. It is surprising, therefore, that there has been no attempt to examine covariation in body size, species richness and geographic range size patterns simultaneously in a single assemblage. Here, we do so, using the assemblage of birds in the New World. The mean body mass of New World birds is lowest in equatorial areas, and increases with latitude either side of the equator, as expected from Bergmann's rule. However, this pattern closely miners that in species richness, and there is a strong inverse correlation between the number of species in an area and their mean body mass. This correlation is stronger than that of either variable with latitude, and hints al a common underlying cause. In contrast, the relationship between the mean body size and the mean geographic range size of species in an area is very weak. Nevertheless, the spatial patterns mean that the interspecific relationship between range size and body size varies across latitudes, which has important consequences for conservation assessments based on species' range sizes. If there is an ecological reason why larger body size is favoured at high latitudes, where energy availability is lower, this could in part explain the coincidence of spatial patterns in body size and species richness. Spatial patterns in range size also may in part be mediated through a weak correlation with body size. Thus, spatial patterns in all three variables may be inter-related.