The flowers of Mountain avens track the movement of the sun across the sky during the day, a phenomenon called heliotropism. Most plants that have similar abilities do so to reduce the amount of solar radiation striking their flowers or leaves. In Dryas, the flowers do the opposite, moving to maximize the amount of sunlight reflecting off the petals and onto the mass of pistils at the center of the flower. Experiments by researchers in Sweden have shown that flowers that track the sun are warmer and have pistils that develop faster and produce heavier seeds than those that are in shade.
It is a circumpolar species found in arctic tundra of northern Eurasia and North America, but also extending southward above tree line in the Cascades and Rocky Mountains to Washington, Oregon, Utah, and Colorado.
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