Table 2.

Histological measurements of lung morphology.

Trait	Treatment	Highlander	Lowlander
Alveolar surface density (μm−1)	Control	0.108 ± 0.003	0.089 ± 0.003
	Adult hypoxia	0.102 ± 0.002	0.091 ± 0.102
	Life-long hypoxia	0.099 ± 0.006	-
Total alveolar surface area (cm2 g−1)	Control	31.44 ± 5.26	27.78 ± 2.03
	Adult hypoxia	35.81 ± 6.59	35.68 ± 2.62
	Life-long hypoxia	44.18 ± 5.11	-
Alveolar density (mm−2)	Control	885 ± 51	770 ± 27
	Adult hypoxia	853 ± 86	661 ± 30*
	Life-long hypoxia	815 ± 73	-

Data are mean ± SEM. N as follows: five control, four adult hypoxia, and five life-long hypoxia for highlanders; six control and seven adult hypoxia for lowlanders.

^*Significant pairwise difference from control within a population using Holm-Sidak post-tests.