Why do phospholipids tend to spontaneously orient themselves into something resembling a membrane?

This aquarium exhibits biotic and abiotic factors in an aquatic environment. one of the abiotic factors is

Match each description to the appropriate biome. tropical savanna desert tropical rain forest taiga tundra has sparse vegetation and very cold temperatures located near the equator and contains trees that form dense canopy layers is very hot and dry, and has plants that need little water has cold winters, heavy snowfall and is dominated by conifers has warm temperatures and is dominated by grasses

What noticeable trend from this graph might be used to make a conclusion?