Mosquitoes
Mosquitoes are known to be harmful insects that feed on blood and transmit dangerous diseases to humans and animals, but only female mosquitoes. This only happens when the female mosquito needs blood to feed its eggs. In fact, the mosquito's favorite food is nectar, not blood. Male mosquitoes drink sugar flower nectar to stimulate themselves for mate-seeking flights. Female mosquitoes also drink nectar before mating.
Whenever you drink nectar, that's when the mosquito collects and moves the pollen. Orchid is the favorite flower mosquito for pollination. Female mosquitoes feed on blood to get the protein they need to lay eggs and reproduce. That is why when biting people and other animals, female mosquitoes can be harmful. In general, however, mosquitoes eat nectar to provide energy for them, to help pollinate flowers, often aquatic plants that they spend a lot of time around, for example, to propagate, thereby helping to maintain these trees.