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RandySF

(59,079 posts)
Sat May 23, 2020, 01:52 AM May 2020

Millions of cicadas are expected to emerge after 17 years underground because, of course, it's 2020

As if we didn’t have enough to worry about with giant murder hornets invading the US and a global pandemic, millions of 17-year cicadas will emerge from the ground this year.

As many as 1.5 million cicadas per acre may emerge, and people living in Southwest Virginia, parts of North Carolina and West Virginia could witness this unique phenomenon, Virginia Tech says in a news release.

Luckily, cicadas are harmless to humans. At most, the noise they make could become a nuisance.

“Communities and farms with large numbers of cicadas emerging at once may have a substantial noise issue,” said Eric Day, Virginia Cooperative Extension entomologist in Virginia Tech’s Department of Entomology.

“Hopefully, any annoyance at the disturbance is tempered by just how infrequent — and amazing — this event is.”

However, they are a danger to orchids, vines and trees due to the egg-laying habits of its females.


https://www.eastbaytimes.com/2020/05/22/millions-of-cicadas-are-expected-to-emerge-after-17-years-underground-because-of-course-its-2020/?utm_campaign=socialflow&utm_medium=social&utm_source=twitter.com&utm_content=tw-EastBayTimes

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Millions of cicadas are expected to emerge after 17 years underground because, of course, it's 2020 (Original Post) RandySF May 2020 OP
I think cicadas are kinda cool. They're the least of my worries LeftInTX May 2020 #1
You find prime numbers in the life cycles of cicadas yortsed snacilbuper May 2020 #2
Each cicada has a unique voice. I_UndergroundPanther May 2020 #3
Bird will have a field day..... Historic NY May 2020 #4
I love peak cicada years jberryhill May 2020 #5

yortsed snacilbuper

(7,939 posts)
2. You find prime numbers in the life cycles of cicadas
Sat May 23, 2020, 02:06 AM
May 2020

There are about 1,500 species of cicadas known. There are those that appear yearly in midsummer, and there are also the so-called "periodic" cicadas. They appear at prime number intervals - 7 years, 13 years and 17 years.

biologists have asked for a long time whether it's just a coincidence that the emergence period of the three species of periodic cicadas (7, 13 and 17 years) are all prime numbers.

One previous theory was that if the cicadas are running on different cycles, and if these cycles are prime numbers, they'll cross over only very rarely. For example, a 13-year cycle and 17-year cycle will meet only every 221 years. That means that both species of cicadas would come out in huge numbers and all have to compete for the same amount of food only once every 221 years. The rest of the time, there would be enough food.

https://www.abc.net.au/science/articles/2001/11/27/421251.htm

I_UndergroundPanther

(12,480 posts)
3. Each cicada has a unique voice.
Sat May 23, 2020, 02:08 AM
May 2020

Their choruses if you really listen to it is otherworldly. It has crescendo's and a rhythm to it. I like the sound they make

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