There are really a lot of mosquitoes in Indonesia..
So..
Those who know about it would know, but they sell mosquito repellent necklaces and such..
You can wear it around your neck or hang it on a bag and carry it..
Only female mosquitoes suck blood..
Male mosquitoes suck honey from flowers..
When female mosquitoes enter breeding season and mate with males..
They search for blood, which is nutrition, to lay eggs..
But since they've already mated..
Male mosquitoes become a real annoyance to female mosquitoes..
When a male mosquito approaches, female mosquitoes instinctively flee..
I guess they're saying leave me alone since I've already taken care of business..
Male mosquitoes emit sounds at specific frequencies..
Using that principle..
That is, a product that repels mosquitoes using a machine that emits the frequency sound that male mosquitoes make was invented..
When that frequency sound is heard, blood-sucking female mosquitoes flee..
The frequency range humans can hear is about 16-20,000 hertz..
I heard that dogs can hear sounds in a wider frequency range than that..
When they surveyed people about the sounds they hate most..
The sound of nails scratching a blackboard..
A woman's scream..
A baby crying.. and so on..
But..
The interesting thing is..
The sounds people hate to hear most
Are in the frequency range that humans are most sensitive to..
It's said to be 2000-5000 hertz..
When you hear frequency sounds in this range
Your heart rate increases and blood pressure rises and such..
We don't fight much now
But back during our newlywed days when we fought a lot
When my wife raised her voice with a "da da da" sound
I felt like I was going crazy..
Irritation.. irritation..
My heart rate really did speed up and my blood pressure rose
Because I hated listening to it so much, I often went outside..
Even when the kids were just born..
Even though I like the kids
I remember getting so irritated when the kids cried while I was sleeping..
Now the kids are all (?) grown up..
And my wife doesn't raise her voice as much as before..
But when I really thought about it..
The sounds people hate to hear most
Are in the frequency range that humans can hear best..
Sounds that are unpleasant but heard most clearly..
When a baby cries and a woman screams, it's because of danger, right..?
Maybe we evolved to detect that danger and take quick action..
That's what I think..
As I was thinking about this
Another thought also comes to mind..
My wife raising her voice and the kids expressing irritation..
These are not pleasant sounds..
To be honest, they're very unpleasant sounds..
Those sounds were actually..
Save me..
It's hard, come quickly and take some action
I think they were SOS signals..
They sent SOS signals but during our newlywed days I didn't know and got more irritated, so..
But now that I know..
That's at least fortunate..
