Any student of the natural sciences understands this conundrum: all species on the planet contain potentially valuable genetic information but large species are always the focal point for the public. No-one really cares if some recently discovered species of beetle becomes extinct because its habitat was destroyed … but if it were a rhino or an elephant … well, that would be a sore loss indeed. What would we tell our children?

In the last couple of decades we’ve built new instruments that can sequence genes quickly and relatively cheaply. This has allowed us to see through a genetic lens for the first time. We sequenced the human genome in 2004 and then used the technology to look at the microbes that live in our bodies – our microbiomes.

Now we can use the same techniques to look at the microbiomes of hunter-gatherers … a reasonable proxy for how we used to be. The news isn’t great. We have lost at least 25% of our microbial diversity. These lost microbial partners almost certainly had some co-evolved function. We can’t even postulate, yet, what these functions might have been.

I want my full diversity back. I trust the result of millions of years of evolution.

What worries me is that some of these species may be gone forever. I may not be able to reinstate my microbial partners and undo the damage that I’ve done to my microbiome.

We know that we’re losing our microbial diversity through massive changes to our lifestyles – the overuse of antibiotics, reduced diversity in our diet, being indoors all day, C-section births, reduced breastfeeding rates and treated water are some of the factors behind this. Right now, there is no way for us to know when a microbe becomes extinct. We have absolutely no idea of what’s out there.

It’s really important to highlight the damage that we’re doing to the world’s ecosystems, so I’m not suggesting that we stop fighting for the rhinos, but let’s also keep an eye out for extinctions that affect us directly but may not make the news.