That is a serious "quotation needed" statement. How can you even know you know about all relevant ecosystems when you are missing 90% of species? Besides, just knowing about the "keystones" of an ecosystem is required but not sufficient.

As an analogy, if you knew the top 10% keystone chemicals that make up the human body but did not know the long tail of the other 90%, you'd likely miss out on a lot of the details that make it all work like immune system cells and vitamins. Just because a molecule (or species) is rare does not make it non-essential.

I hope we are building a statistical model of which one is eating which to map where are the missing pieces of the puzzle and direct our focus of research.

> all the ones that matter

Could you explain? Dow we know of all the viruses/ bacteria/ trees/ insects that 'matter'?