Toby Kiers, the Jane Goodall of fungi and mycorrhizal networks on being an underground astronaut

Toby Kiers, Executive Director & Chief Scientist at SPUN (Society for the Protection of Underground Networks) shares about their research into the mycorrhiza network, mapping biodiversity, DNA sequences of mycorrhizal fungi and a lot more about the wonderful world under our feet. She is the Jane Goodall of fungi (according to the words of previous guest Rose Marcario, former CEO of Patagonia).


Welcome on board this spaceship, which won’t take you up to space but to the magical world underneath your feet. Everything literally starts with the relationship between fungus and plants, and we hardly ever talk about them. So, what does that mean for farmers and investors, and why is this so exciting now?


It was 450 million years ago when plants first started associating with fungal symbionts. Were the ancestors of the mycorrhizal fungi that allowed plants to first colonize land 450 million years ago. And what you have coming out of that is the basis of all ecosystems, the basis of all life on Earth. The structures that grow inside root cells, is the mycorrhizal fungi. They penetrate into the cell of a root and they form arbuscular structures, which look like mini trees inside a cell. The plant feeds carbon to the mycorrhizal and the mycorrhizal provide phosphorus, nitrogen, zinc and many more things that you can see with a microscope.

“These first proto plants were in harsh conditions of land, those nutrients were very hard to get to, they’re all sequestered in rock. Fungi are good at eating rock, right? Fungi can break apart those complex molecules and feed them to plants in a usable form. And so it’s because of that symbiosis, that plants are actually able to first colonize land. And in return, of course, it’s quite hard for fungi to get carbon. And so as plants, we know, we’re photosynthesizing and making carbon, they were feeding it to the fungal network.’ – Toby Kiers

“You would just dig up roots, and you would clear them, you know, with acid and all kinds of things. And then you could see the fungal network that had penetrated into the cell, you’d stain it blue.” – Toby Kiers

“Plants feed carbon in the form of sugars and fats, what an amazing meal… the plant is feeding the fungus, sugars and fats. And in return, the fungus is foraging in the soil and it’s looking for phosphorus and nitrogen that it trades in this reciprocal exchange with the plant. And so that’s what the arbuscule is, it’s the site of nutrient exchange in the root, it penetrates into the root” – Toby Kiers

“Mycorrhizal networks are a type of symbiotic fungi that colonize roots of the majority of plant species on Earth. So between 70% and 90% of plant species are colonized by these mycorrhizal fungi.” – Toby Kiers


According to Toby, fungi lie the base of ecosystem health. One of the things that Spun is trying to accomplish is to bring a mind shift that involves us viewing above ground ecosystems as consequences of what’s happening below ground. There’s a lot happening in the soils, that if we had the right way of understanding them, that can be used to help manage what happens above ground. When we watch the flows inside these networks, there is a language of how nutrients are being moved.

“It changes also the way that we approach conservation and climate agendas, it changes the way that we do science, because the priorities are not always on things that we can see. And the monitoring is not on always the things that we can monitor above ground. But maybe we need to develop new ways of monitoring the health of these networks underground. And what would that look like? And can that give us an early warning of things to come?” – Toby Kiers

“The soils are basically a narrative of so much of what is happening, they are a blueprint for who was there, and where they were and what they were doing. We just don’t know how to read them. I mean, that’s maybe also a bold statement. But there’s a lot happening in the soils, that if we had the right way of understanding them, they tell a story that can be used for us to help manage what happens above ground.” – Toby Kiers


According to Toby, something that is happening right now and is really exciting and cutting edge is the DNA sequencing of the microbial communities. Their work allows them to correlate diversity patterns with ecosystem attributes, and to asnwer questions like how much carbon sequestration is happening on that pixel of Earth? what are the nutrients? what are the temperatures? That way, they can start to make these correlations between who is there and what they’re doing.

“There’re techniques to actually try to get the function of these mycorrhizal networks, just from their DNA sequencing. Are they good at carbon sequestration? Are they good at nitrogen? […] So that’s one thing I would say, on the global scale is really trying to get more at how can we take these long reads sequences and get it function, and then start mapping those functions. So we’re looking at correlations between certain fungal communities and what’s happening above grounds.” – Toby Kiers

“But I think the work that is really exciting, looking forward, if we’re in this big room of investors, is really trying to develop new techniques to make the invisible, visible. And there’s lots of ways of doing that […] I really want to stimulate innovation in that area. Because I think that’s going to make life much easier for farmers if they can understand and visually understand what’s happening underground. And some of this stuff sounds kind of sci fi at this point, right. But technology is moving pretty fast.” – Toby Kiers


At SPUN (Society for the Protection of Underground Networks) they are now building what they call v1 (version one), of these biodiversity maps for the earth. They are working with two organizations, Global Fungi, and the Crowther Lab, which is at ETH Zurich, to make the first high-resolution predictions of biodiversity underground for mycorrhizal networks. It’s an iterative process. The machine learning predictions get better and better, the more data that they feed into the predictions. They want to be able to use these predictions in conservation agendas and to be able to identify biodiversity hotspots, places on earth that have very unique fungal communities and to say ‘this is a place that we should prioritize in terms of conservation.’

“We are working on mapping the biodiversity. So really trying to understand the sequences, the DNA sequences of mycorrhizal fungi and how these communities differ across all the different ecosystems of the world. So everything from pristine forests, which I think a lot of people associate with mycorrhizal fungi, but also ecosystems that I think would surprise you, desert ecosystems, dryland ecosystems, places where you don’t normally think of fungi and pristine habitats, but also a managed ecosystem. So we’re really interested in microbial communities in agricultural systems, in forestry systems, trying to get a baseline understanding of who is there and what they’re doing.” – Toby Kiers

“We’re working with about 10,000 samples of DNA sequences from all around the world. And we use machine learning algorithms, which allow us to add in different ecosystem changes in the habitat, for example, how the habitats are different in different places on earth. If you put those maps, all of these layers of environmental data together with the samples that have been taken, we can start making predictions about what these underground systems look like.” – Toby Kiers


Koen and Toby also talked about

  • The different expeditions,
  • Fungicide, fertilisers and how bad is that for fungal networks,
  • Making the invisible underground life visible
  • Fungi are farming plants
  • Acoustic landscapes of different soils




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The above references an opinion and is for information and educational purposes only. It is not intended to be investment advice. Seek a duly licensed professional for investment advice.

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