Soil Evolution
How Our Soil Got Here
If soil is a 'natural body'
Then - like all life - it must have evolved.
But, how, when, what, where, and why?
THE ORIGIN OF SOILS
BY MEANS OF NATURAL SELECTION
If the soil is a 'living entity', then it must have evolved.
This, according to Darwin’s theory, would have been by means of 'natural selection'.
This site picks up from where Darwin left off ...
A Ground-breaking Piece of Soil Ecology'
Biological Recording Company with Kerry Calloway
My question. Did Charles offer a view of when/how earthworms evolved?
Kerry: "I’ve not seen any reference from Darwin regarding earthworm evolution. He doesn’t talk about this in his earthworm book and I don’t recall them being mentioned (at least in any significant way) in On the Origin of Species." I believe it is around 200 mya
Have you ever wondered: "How did all that heavy brownish soil stuff get under my feet?" There are one and a half tons in per cubic meter of healthy soil, equivalent . In terms of life, can you imagine a medium sized whale crushed up into that volume?
While many call this planet 'Earth', most of us take this brown stuff for granted. Yet it must have come from somewhere at some time in history. All the different creatures and constructs which make 'soil' so unique could not have arrived together. So how did all this soil get here?
This, I believe, is the first time anybody has worked out in detail how soil evolved and came to be under our feet. (is a Japanese version).
The complex story of how life came on to land is often called 'terrestrialisation. When using this term, there is talk about 'colonisation of land', as if the organisms establish themselves 'on' land. That could not have happened without soil, yet most versions of terrestrialisation do not include soil - often because they are written by non-soil scientists. Animals and plants would soon die, as they could not have developed adaptations to dry life on land overnight, but would require a very long time. Here we talk of the 'construction of soil' as that key to life on land. That construction could not have been a single event, but evolved millions of years, sometimes slowly sometimes in bursts.
This site aims to:
Bring the soil to life, showing the underground architecture of soil cities and their inhabitants.
Work out how soil came to be here, as it evolved over millions of years.
Develop better understanding of the functions of soil and how that may help us in the future.
This is the best graphic to date to outline early soil evolution - from Royal Society
There is no sign of soil - as we would recognise today (although various sorts of 'palaeosols' date back over 3.5 Ga) for the first 4 billion years on this planet. During this time there were powerful physical, chemical and biological reactions between land, air, and water, but it is only the last tenth of the life of planet earth, that soil as we know it has developed. Only recently have we recognised that soil is a living entity. If so, it must have evolved. We will dig deep to unearth lots of research to find out about how this evolution involving animals, plants, and minerals took place over hundreds of millions of years. What makes soil so special?........
The soil can be considered as a 'living entity'
Various forces help form different soil types
In the previous century, there two main theories of soil science were to do with rock weathering and systems for balancing nutrients. Then a group of Russians came along and said soil was an ‘entity’. 'Entity’ is a useful term for soil as soil does not have such an organised structure like an organism but has more structure than an ecosystem. An ‘entity’ says it is something we can identify and study as a discrete body. Later the term 'living entity' was coined (by Hyams) . If it is a living entity, and you believe in Darwin’s theory of evolution, soil must have evolved. Yet I don't think there is an overall description of how all that life and all the various processes in soils came into being. Soil is similar all over the world. How did that happen ? This site attempts to work out just that.
Today many people, who agree with soil as a living entity, see it mainly as worms and microbes, a sort of ‘microbial mush’. Yet the soil consists of amazing strong 3D structures for small creatures and other organisms to live. It is much more than a 'mush', more like city. How did this happen?
If you search for 'soil evolution' on your favourite search engine, it often leads to 'soil formation'. This describes how five “state factors” - parent material, topography, climate, organisms, and time produce the various well characterised soil types. This takes place over hundreds or thousands of years and much of the science of soil - pedology - occupies itself with this soil formation.
Here we go back much further. 'Soil evolution' looks to work out when, where and how the soil functions that enable that formation came into being. The particular organisms and processes that turn sand silt and clay into the various soil types all over the world came into being during the last half billion years. We are going to pick up all sorts of recognised scientific research, from decades ago to the most recent times, to try and piece together how soil developed into the hidden living entity beneath our feet today.
Where quadrillions of creatures run round
Waiting to be discovered
Out of sight, there are ‘quadrillions’ (in UK alone) of creatures with bodies legs and eyes, moving around all the time and all over the world in just about every nook and cranny. Their total weight is equal to earthworms in any given amount of soil, only there are thousands more of them. These arthropods have been around much longer than earthworms and play a key part constructing the soil civilisation. They have vital relationships with the plant roots, bacteria and fungi in soils. Yet, it is only recently these soil invertebrates are getting the attention they deserve.
I wish we had a soilscope that we could put into the ground and see what is going on. Despite all sorts of 'scopes', for looking into space, down peoples' throats, and round corners, we have never invented one for soil. If only we could look into that world. But we have not conquered the laws of light to see into the dark underworld..
And nobody has thought to look backwards hundreds of millions of years to see how the soil came to be here. All those tons of life. As a living entity it must have evolved. But which functions came first, when were the first small animals. What came first - AMF or nitrogen fixing nodules? They are related but AMF was on the earth three hundred million years before nitrifying bacteria..
What on earth has gone on underground for millions of years, out of sight and virtually unknown?
We are going to use old-fashioned detective work, along with state of the art science, that can see beyond the human eye, to unearth what has gone on in the past. We will leave no stone unturned. As a scientific sleuth I want to use all the techniques and tools, particularly those involving fossil evidence and molecular mapping, to discover what went on. New techniques, like metagenomics, are emerging to map soils, but they do not have the definition of those old fashioned skills that recognise the shapes moving about. I want you to join me, just like most detectives have an assistant to point out their errors, to help ascertain the available evidence uncovered as to what is going on, and what has gone on to get here to create the soil we know.
You can evaluate the work this scientific sleuth is uncovering. To make sense of this hidden world, lots of different perspectives are needed. Can you bring yours to see this world from different angles, where the creatures are barely visible. As much as possible, evidence will all come from peer reviewed work. However when reading that work, imagine you are looking down a long pipe, and you cannot see the rest of the goings on outside that pipe. That is what scientists have to do. What we have to do is make the connections between what can be seen down those pipes, but also what goes on between the pipes - which we cannot see. Our job is to put all those insights together. Pick up the challenge here.
The previoulsy untold 'story of soil' sees soil in a new way.
Here we try and work out how the soil evolved from sparse beginnings to those tons of living material under our feet. By following its development, we may be able to make more sense of some of the great mysteries that went on above ground, like insects' emergence and flowering plants' rapid explosion.
We are going to do this as if we were a tiny animal (about 0.05% your size) moving through dark deep damp tunnels - the brown planet - for hundreds of millions of years.
Malling Rhizotron looking at their rootstocks