Sounds reasonable.

Let me think: if the average weight of a human is 60 kg and there are 8 billion humans in the world, there are 480 billion kg of humanity on the planet. Call it 500 billion kg.

The Smithsonian estimates that "At any time, it is estimated that there are some 10 quintillion (10,000,000,000,000,000,000) individual insects alive." If the average insect weighs 5 milligrams, then the total weight of all insects is 50,000,000,000,000,000,000 mg = 50,000,000,000,000 kilograms, or about 100 times as much as the total weight of all the humans. Hmm... actually if I'd read the whole article, https://www.si.edu/Encyclopedia_SI/nmnh/buginfo/bugnos.htm , I'd have seen that it says "A recent article in The New York Times claimed that the world holds 300 pounds of insects for every pound of humans." Anyway, there is at least 100 times as much insect mass on the earth as there is human mass, so it makes sense that losing all the insects would have a much larger impact than losing all the humans.

Sara Teasdale wrote:

There will come soft rains and the smell of the ground,

And swallows circling with their shimmering sound;

And frogs in the pools, singing at night,

And wild plum trees in tremulous white,

Robins will wear their feathery fire,

Whistling their whims on a low fence-wire;

And not one will know of the war, not one

Will care at last when it is done.

Not one would mind, neither bird nor tree,

If mankind perished utterly;

And Spring herself, when she woke at dawn,

Would scarcely know that we were gone.

Yes, that is true because after extention of human being there will be no one to transform the environment except the Nature.So obviously, if nature will involve in building the world then all forms of life will be flourished.please correct me if I'm wrong

It's probably true. Of course I don't advocate the erradication of human beings, but I'd like to see the population controlled and and eventually brought down to the 3-4 billion range. Although every animal's instict is to multiply and produce as many offspring as possible, I like to think we are smarter than that. Look at the incredible irreversible damage our great numbers are doing to the planet. Unfortunately there are many groups that urge their followers to have as many children as possible, regardless of the consequences, even if they can support them, in an effort to become stronger by numbers. I would like to see all major groups denounce this practice, but it will probably never happen.