Sunflower is a sleepy little guy. It just wakes up at 10 in the morning and blooms colorful flowers, but after noon, its flowers are closed and go to sleep. On a cloudy day, it seems to be very playful and will not enter the "dream" until evening.
Some flowers sleep during the day and wake up at night, and the circadian rhythm is reversed. For example, Mirabilis jalapa blooms around 5 pm, and at dawn the next day, the flowers close and start to sleep, as if afraid of seeing the sun. There are many smiling flowers in the moonlight, such as moonlight flower, cordate telosma, cordate telosma and so on. , are closed during the day and open at night. Even more interesting is saffron, which blooms in early spring. During the day, they sometimes turn on and off, wake up and sleep, sleep and wake up-several times a day!
Why do plants sleep? It turns out that the sleep of plants is an exercise for them to adapt to the surrounding environment and protect themselves. During the day and night, there are obvious differences between light and dark, high and low temperatures and different air humidity. Plants gradually form their own sleeping habits in the process of long-term natural selection.
There are also flowers that bloom during the day and close at night, such as water lilies and tulips. Why is this? The phenomenon that flowers bloom during the day and close at night is the sleep movement of plants. This movement is caused by temperature change, and it is closed at night when the temperature is low. If the closed flowers are moved to a warm place, they will reopen in 3-5 minutes. The other is caused by the change of light intensity, such as flowers opening in strong light and closing in weak light.