While many types of insects, birds and animals seen in the home are unwanted intruders, others play a vital role in pollinating plants and moving seeds from one place to another. In fact, without these animal and insect helpers, most plants would be unable to reproduce.
Even though most gardeners understand how important this cycle of pollination and seed disbursal is, few fully understand why it occurs, or how it benefits both the plants and the animals.
The rewards of pollination and seed disbursal to the plants are easy to determine – they get to spread their seeds far and wide, and start new plants in far off locations. The rewards the insects, birds and mammals derive are many as well, and they include:
The use of nectar and the plants, insects, birds and animals that depend on it is a fascinating study in co-evolution. The sugar concentrations of many plant nectars have evolved to match the energy requirements of the types of animals, birds and insects that pollinate them. For instance, bees require a 30-35% concentration of sugar in order to make the honey needed by their larvae in the winter. Therefore, bees will not visit flowers whose nectar contains less than 30% sugar. Therefore, the flowers and plants that depend on bees for pollination have evolved high concentrations of sugar in their nectar to attract these pollinators.
Of course, this pollen and nectar does the plants no good if the birds, insects and animals cannot find it, and plants and flowers use their bright colors and strong scents to attract these animals and let them know that pollen, nectar, or both await them.
Some pollinating species rely primarily on their sense of sight, and the bright flowers are used to attract their attention. Other species, particularly nocturnal ones, rely primarily on smell. It is the scent of the flowers that attracts these scent oriented pollinators.