I was recently beset by a plague of clothes moths. After hours of research, I discovered the miracle that is the parasitic wasp, or Trichogramma evanescens – near-microscopic beasts that you can order online (in sachets of 2,000 wasps!), the life’s calling of which is to destroy clothes moth eggs.

It made me wonder: is there anything else in our daily lives that is so beneficial to us, but which few of us have heard of – or realise is there? John Forward, Brixton

Send new questions to nq@theguardian.com.

Readers reply

Our gut bacteria. Without them, there would be no helping us, as we’d not be alive to be helped. jtappin

Bacteria. They do everything from helping you digest your dinner to seeing off alien invasions. SpoilheapSurfer

I recently read about the microbes that inhabit our bodies. It’s believed that we have more microbes than human cells in and on our bodies. This leads me to think that they are a significant kind of organism that we’re reliant on without realising. d33pf1x

“You are for them the ultimate food court, with the convenience of warmth and constant mobility thrown in. By way of thanks, they give you BO” – Bill Bryson. EddieChorepost

Phytoplankton. They absorb carbon from the water then, when they die, sink to the bottom of the ocean, making them a carbon sink in every sense of the word. Mike345

Without honey bees, our ecosystem would face a global, catastrophic crisis, resulting in severe food shortages, dire economic impact and the potential collapse of many plant species, leading to reduced biodiversity. Sagarmatha1953

Bees are not the only pollinators around. The problem is that all of them are decreasing in numbers. nina1414

Mushrooms, or fungi, have many uses, including helping trees to survive, a fact that few people who are concerned about climate change and vanishing forests are entirely cognisant of. RPOrlando

Trichogramma are useful to humans not only in household work, but also in agriculture. As we all know, agriculture is the basic need of human beings. Trichogramma chilonis and Trichogramma japonicum are used as biocontrol agents, as they feed on the larvae of some serious pests that hurt farmers’ incomes as well as ecological and public health. Similarly, green lacewing (Chrysoperla spp) grubs are used to control sucking pests, reducing chemical dependence and fostering a safer environment. These grubs are mass grown in labs and released in fields at 10,000 a hectare to control pest population. Abinash Das

Without earthworms, we wouldn’t have enough food. They aerate the soil, which roots need, and their waste (from eating soil) makes nutrients bioavailable to plants. JSME

Yeast. As someone who loves bread and alcohol. It is miraculous stuff. Anomander64

The robber fly doesn’t bother humans, but kills the things we see as pests; I watched one killing ants in my yard. I’ve learned they can kill mice – important at a time people have become more aware of hantavirus. Ted Coombs

Diatoms are responsible for 50-60% of the free oxygen in our atmosphere. Put that in your pipe and smoke it. MrJustin

I remember hearing about an old lady who bought some parasitic wasps. She bought the wasps to swallow the moths that swallowed her cloth(e)s … EddieChorepost

I don’t know, because I don’t realise how beneficial they are. 1AngryMan