Final answer:
Hummingbirds migrating to the U.S. from Mexico engage in a spring migration for breeding and resource access. They also play a key role in pollination, having a symbiotic relationship with flowering plants. This migration is part of a repeating natural cycle fundamental to their survival.
Step-by-step explanation:
Hummingbird Migration
The hummingbirds migrating from Mexico to the United States in the spring are engaging in a behavior known as migration, which is similar to the well-documented Monarch butterfly migration. These migrations are instinctual patterns of movement, where entire populations move from one habitat to another based on the seasons to ensure survival, breeding, and access to resources. In the case of hummingbirds, as well as Monarch butterflies, they travel thousands of miles to reach their breeding grounds, taking advantage of warmer climates and abundant food sources.
During the migration, hummingbirds also play a crucial role in pollination. They have a symbiotic relationship with flowering plants where they obtain nectar for energy; in return, they pollinate the flowers, ensuring the reproduction of these plants. This symbiotic relationship has evolved over time through co-evolution, making them highly effective at their respective roles.
Migratory patterns like those of hummingbirds and Monarch butterflies are part of a natural cycle that ensures the survival of species, allowing them to take advantage of different environments and resources throughout the year as depicted in various scientific observations including the famous migration of Swainson's hawks illustrated in migration maps.