A recent paper published in Trends in Ecology and Evolution sets out the increasing evidence that loss of large vertebrates in particular, is having massive impacts on ecosystem processes.
The article stops short of explaining why (which is the subject of this blog and my forthcoming book) but the scientists rightfully recognise the need for conservationWhy is animal conservation important? Animal conservation is important, because animals are the only mechanism to create biodiversity, which is the mechanism that creates a habitable planet for humans. Without animals, the energy from today’s plants (algae, trees, flowers etc) will eventually reach the atmosphere and ocean, much of it as carbon. The quantity of this plant-based waste is so More to “restore ecological functions at landscape scales”, even drawing the all-important link between biodiversityWhat is the definition of biodiversity? When we ask, what is the definition of biodiversity? It depends on what we want to do with it. The term is widely and commonly misused, leading to significant misinterpretation of the importance of how animals function on Earth and why they matter a great deal, to human survival. Here I will try to More and climate change.
… the Paris Climate Agreement requires the Earth system to play its part in the global carbon cycle. The restoration of megafaunaThe largest animals that represent the top of the trophic pyramid. These are the final building blocks in ecosystem structures for maximum entropy production. Megafauna can be measured at any spatial scale. The largest animal that ever lived on Earth is the Blue Whale. In a grassland, spiders could be considered megafauna The term is generally reserved for animals larger More and their functional roles will need to be a key part of any nature-based climate solutions.
However, it’s not all about large megafauna. Steady stable-state(of an ecosystem) where free surplus energy is minimised, where there is maximum entropy production and minimum waste. In such a system, there is expected to be relatively small fluctuations in atmospheric and other chemistry and where disruption or disturbance occurs, the resulting changes can be absorbed quickly by a succession of new plants and animals that enter to fill More ecosystemsHow ecosystems function An ecosystem is a community of lifeforms that interact in such an optimal way that how ecosystems function best, is when all components (including humans and other animals) can persist and live alongside each other for the longest time possible. Ecosystems are fuelled by the energy created by plants (primary producers) that convert the Sun's heat energy More will require all animals in correct proportions. Tackling things at the systems level will mean reconnecting habitat and repatriating wildlife into the cycles that create clean water, fertile soil, rich fisheries and stable climate.
I have amended the article’s main diagram (below) as I think it fails to represent the magnitude of the risk for human existence. Animals aren’t at the centre, separated from earth systems. Animals are a consequence of processes that enabled ecosystems to stabilise. After all, it was only the rise of animals that gave life to humans (another animal).
In my version of the diagram (above), I have placed the physical and chemical structures at the centre. These are what determine the likelihood of human and animal distribution and relative abundance.
The consequence, in terms of climate stability and food security, is built on top of this by animals. This is the thin fabric that creates a habitable Earth for us … the stable climate and food security that it delivers, that enables humans to survive, are all animal-driven.
Our position is among the animals but for clarity sake, I’ve excised humans into their own concentric circle on the outside. The two-way arrows are there to indicate that the concentric systems are all interconnected. They are non-linear. However, humans exist mostly in the outer three domains. Primary producers like plants would do just fine without us, although their existence without animals would destabilise the Earth’s atmosphere and oceans.
Humans and animals exist in the outer-shell, locked into a shared past and future, by evolution, which favours not single animals, but communities that are best adapted together, to maintain ecosystems in a steady stable-state – the state that delivers our food. Climate stability and food security are tied to one another by animal impactWhat is Animal Impact? Without wildlife, Earth would not be habitable for humans, because it's animals that stabilise ecosystems. It’s a fundamental law of nature that animals (and humans) exist because we are the most likely lifeforms to minimise environmental chaos. Animal impact, therefore, is a measure of how much all wildlife is collectively responsible for creating a habitable Earth. The More* because they are the only thing that stabilises the chaos(Of energy and ecosystems). Ecosystems are thermodynamically driven. Disorder occurs when energy dissipates and becomes more chaotic. For example, the release of hot air into the atmosphere results in that energy is freer to disperse (maximum entropy). The opposite is true when energy is locked into biological processes, when it is stored inside molecules (minimum entropy). Stability in ecosystems occurs More that would otherwise be wrought by primary producers on the landscapes and seascapes.
*Because we burn fossil fuels, we tend to think of climate change as being driven by carbon burning. Of course it is, but that’s got nothing to do with how ecosystems naturally work. In the absence of any fossil fuel burning, the process that stabilises Earth’s carbon chemistry is driven by animals. While we are preoccupied with addressing fossil fuel burning, we overlook the massive impact on ecosystems that mass extinctionAnimal life hasn't existed for very long on planet Earth. In the last 500 million years, there have been five mass extinctions, defined as events that wiped out at least 75% of animal life. The Devonian mass extinction is considered to have been caused by the rise of plants on land, which polluted the oceans in the absence of animals. More is having, as this is destabilising the underlying mechanism.
