Every spring, small flying insects visit flowers in parks and gardens. From March to May, these insects become active again after winter. Scientists say their work is very important for our food. Without them, many plants cannot make fruit or seeds.
The FAO is a food organization at the United Nations. It says 75 percent of the world's food plants need these insects. One in every three bites of food depends on them. Without them, people cannot get much of their food.
Here is how it works. An insect visits a flower and gets food from it. Small powder from the flower sticks to its body. It carries this powder to the next flower. This helps the plant make fruit and seeds.
Scientists have found more than 20,000 types of these insects around the world. One group can have between 50,000 and 60,000 insects, with one queen. Butterflies and other small insects also help plants in the same way.
These insects face big problems. People are building roads and buildings, so insects have fewer places to live. Dangerous sprays used on farms can kill them. Climate change also changes when flowers open.
In South Korea, many groups of these insects have died in recent years. This has happened in many other countries, too. The United Nations chose May 20 as World Bee Day in 2017 to teach people about this problem.
People can help. Planting flowers gives insects food. Avoiding dangerous sprays in gardens is helpful. Even a pot of flowers on a balcony can make a difference.