It's scary to think about it! Water drips from trees on hot days. What is this unknown slime?

Every summer, especially in midsummer, you can hear the chirping of insects in the roadside parks. At this time, have you ever walked under a tree and always felt water dripping on your body? It's not the water dripping from the air conditioner, the tree is not sweating from the heat, and there is no bird pooping on your head. What's going on?

This could be cicada urine!

On July 2, a photographer from Xiamen Radio and Television discovered that "cicada urine was raining" under a tree in front of Xiamen University's Furong Tunnel.

Cicada on the tree

Why does urine pour down like rain?

Cicadas are animals that mainly feed on plant sap. After the sap enters the cicada's body, it will absorb the sugar and amino acids in it, and the remaining liquid will be excreted from the body.

Generally speaking, humans and other animals weighing more than 3 kg will spray out a stream of urine when urinating, while some lighter and smaller animals (such as many insects and small mammals) do not spray out a stream of urine. Their urine comes drop by drop.

Cicadas are an exception! These two-gram insects also eject long, thin streams of urine, just like larger mammals.

Cicada peeing. Image credit: Wilson Walker

Not only that, but the latest research has found that the stream of water when a cicada urinates is very powerful - it can spray urine at a speed of up to 3 meters per second, which is the fastest of all the animals evaluated in this new study (including mammals such as elephants and horses)!

Cicada urination behavior is difficult to study because they usually stay high up in trees and, even if people find them, they can easily be startled and fly away. Image credit: Jelbuilder

Expert analysis

She Zhenjia, a senior engineer of the Pest Control Department of Xiamen Greening Center, said that adult cicadas mainly rely on absorbing nutrients from tree sap. After sucking sap, the cicada's body becomes heavy. Once affected by the outside world, they have to quickly expel the sap in their bodies to reduce the "burden" and facilitate flight. Therefore, the liquid sprayed from the tree is, to be precise, the sap that the cicada absorbs into its body, not "urine", and is non-toxic.

Experts suggest that if citizens find the chirping of cicadas disturbing, they can take physical noise reduction measures, such as closing windows, turning on air conditioners or wearing earplugs. Cicadas can be caught with insect nets to appropriately reduce the number of cicadas in the community.

Experts say that hearing the chirping of cicadas indicates that the city's ecological environment is improving. In theory, it is not recommended to do too much human intervention on cicadas. " If we can't hear the chirping of cicadas in a summer, it means that the surrounding ecological environment has deteriorated to a certain extent, " said She Zhenjia.

Netizen comments: First time knowing

Under the video, many netizens expressed their horror at the thought, thinking that they might have been peed on!

"So it wasn't water that fell on my face when I passed under the tree."

“I thought it was air conditioning water”

Some netizens also said that this “urine pouring down like rain” was too exaggerated.

“Too much exaggeration”

“This ‘rain’ looks like a special effect.”

"It's a heavy rain of cicadas"

Some netizens joked, don’t let the people of Shandong see it!

"It's all gone here, 200 per pound."

"People in Shandong will drool when they see so many cicadas."

"In Shandong, they are eaten before they shed their shells. The chirping of cicadas has decreased in recent years."

On social media, there are other people sharing their own experiences of "urine rain"↓↓↓

And it also pees

Every time we see a mosquito sucking blood from our body, we instinctively slap it to death. Next time, before slapping it to death, you can take a closer look to see if there is a drop of liquid at the end of its abdomen. Yes, that is its urine!

As for the reason why mosquitoes urinate, it is different from that of cicadas. On the one hand, it helps to cool down, and on the other hand, it helps to maintain the balance of water and salt in the body.

Planning and production

Source: Morning News

Editor: Yang Yaping

Proofread by Xu Lailinlin