Phenotypic differences between highlanders and lowlanders in Papua New Guinea.

Area of Science:

• Human evolutionary biology
• Physiological adaptation
• Anthropology

Background:

• Altitude poses significant environmental challenges to human populations globally.
• While adaptations in Asian, American, and African highlanders are documented, Oceanian populations remain understudied.
• Papua New Guinean highlanders have inhabited high altitudes for at least 20,000 years.

Purpose of the Study:

• To investigate phenotypic differences between highlanders and lowlanders in Papua New Guinea.
• To test the hypothesis of distinct biological adaptations to high altitude in this understudied population.
• To identify specific traits associated with long-term high-altitude living.

Main Methods:

• Data collected from 162 individuals from high (Mont Wilhelm, 2,300-2,700 m a.s.l.) and low (Daru, <100m a.s.l.) altitudes in Papua New Guinea.
• 13 altitude-related phenotypes were measured, including body proportions, pulmonary function, and circulatory system markers.
• Multilinear regression analyses were used to compare highlanders and lowlanders.

Main Results:

• Six phenotypes showed significant differences between highlanders and lowlanders.
• Highlanders exhibited shorter stature (p=0.001) and smaller waist circumference (p=0.002).
• Significant differences were observed in lung function (larger Forced Vital Capacity, FVC; p=0.008) and circulatory markers (higher hemoglobin concentration; p=3.36e-4).

Conclusions:

• Papua New Guinean highlanders possess specific phenotypes potentially linked to altitude adaptation.
• These findings suggest that, like other global populations, Papua New Guineans have evolved biological strategies for high-altitude survival.
• This study contributes to understanding human adaptive diversity in Oceania.