You may have noticed that in the summertime at a barbeque or around the pool, you are more likely to get an insect bite than in the middle of the day. The reason for this is that the flowers put out more of the special scents around sunset. Many flowers open up at night making it easier for insects and birds to pollinate them. During the day the scents of the flowers can dry up but as the temperature cools at sunset you have the perfect conditions to attract more bugs to your backyard. The purpose of the insects interaction with the flowers is to reproduce more flowers. Each flower has a male part called the pollen which is carried to the female part called the stigma. With pollination, the flower can form the seeds to reproduce. Examples of insect pollinators include honeybees, bumblebees, moths and butterflies.
The aroma that attracts insects comes from the petals and the nectar glands located inside the flower. When an insect enters a flower to collect nectar, pollen grains cling to its body. As the insect moves from flower to flower, it leaves the pollen on the female part of the flower called the stigma which then triggers the process of pollination.
In mammals, smell plays a role in reproduction. While smell is less important to human reproduction than for insects and other animals, there are perfumes known to attract males to females and females to males. In humans, there are many perfumes which claim to have pheromones, but scientific research has not demonstrated any chemical pheromones in humans. Nonetheless, musk perfumes for men and flowery scents in women continue to be advertised as attracting the opposite sex.