For illustrative purposes, in this article we use “Johansen Plots” as a graphical way of simultaneously visualizing the inter-connected variables that compose the convective steps of the gas transport cascade. These plots are used to reflect on some of the physiological characteristics seen in five species of birds, four of which sojourn to, or are native to, high altitudes (the barnacle goose, bar-headed goose, Andean goose, speckled teal and ruddy duck). These species were chosen to emphasize the diversity of responses to hypoxia that can exist within a single family. This diversity likely arose for many possible reasons, including local adaptation to hypoxia, differences in flight or diving abilities, or as a result of other phylogenetically-based differences across waterfowl in physiology, behaviour, and/or life style.

出于说明目的，在本文中，我们使用“约翰逊图”作为同时可视化构成气体传输级联对流步骤的互连变量的图形方式。这些图用于反映在五种鸟类中观察到的某些生理特征，其中四种鸟类栖息于或原生于高海拔地区（藤壶鹅，长头鹅，安第斯鹅，斑点蓝绿色和红鸭子） ）。选择这些物种是为了强调单个家庭中可能存在的对缺氧反应的多样性。这种多样性可能是由于许多可能的原因而出现的，包括局部适应低氧，飞行或潜水能力的差异，或者由于水禽在生理，行为和/或生活方式上的其他基于系统发育的差异。