By their scent, by the food some flowers offer (pollen and nectar) and by the colours of the flowers.
flowers
to attract birds and insects
Insects birds berries flowers snails spiders scorpions
Flowers attract by smell and color, but some birds are attracted to pine cones, like the various species of finches called crossbills.
Because insects can see purple, blue etc. better than red, orange etc. That's why tropical red flowers are almost always pollinated by birds, and red berries are eaten by birds; birds can see red better, insects can see blue better. Insects are also quite good with ultraviolet light, which is why many flowers have markings that are invisible to us, but visible to them - they can see colours beyond our vision.
Colorful flowers are usually pollinated by attracting pollinators such as bees, butterflies, and birds with their bright petals and sweet nectar. These pollinators are drawn to the colors and scents of the flowers, and in the process of feeding on the nectar, they transfer pollen from one flower to another, aiding in the pollination process.
Flowers that resemble birds are significant in botany and horticulture because they attract pollinators like birds and insects, aiding in the plant's reproduction. Additionally, these unique flowers can also be visually appealing and serve as a point of interest in gardens and landscapes.
Insects and birds visit flowers to feed on nectar and pollen, which provide them with energy and nutrients. In the process, they unintentionally aid in pollination, transferring pollen from one flower to another and helping to fertilize plants for reproduction.
Most red flowers are pollinated by birds rather than insects because birds, particularly hummingbirds, have a high sensitivity to the red spectrum of light, making red flowers more visually appealing to them. In contrast, many insects, such as bees, are more attracted to blue and ultraviolet colors and may overlook red blooms. Additionally, bird-pollinated flowers often produce more nectar and are structured to accommodate the feeding habits of birds, which aids in effective pollination. This adaptation enhances the reproductive success of red-flowered plants in environments where bird pollinators are prevalent.
They don't need to attract animals to their flowers. Flowers that are colorful and have a strong scent attract animal pollenators, such as insects and birds.
It is known that the floral part that attracts insect pollinators is called the petal.
Yes, insects are needed to pollinate some flowers but no, they are not needed to pollinate all flowers. Insects count -- along with bats, birds, and some mammals and reptiles -- among nature's pollinators.