Their dams change the local environment and benefit many animals:

https://www.dailymail.co.uk/sciencetech/article-7217451/Beavers-dams-useful-environment...

"An array of different animal species benefit from having beavers in their environments because they boost biodiversity, researchers claim.

"The semiaquatic rodents were capable of facilitating many groups of organisms to thrive near beaver patches including moose, otters, and weasels.

"According to the study, they do this by preventing drought, carbon sequestration, flood management and keeping streams cool.

"The team, from the University of Helsinki in Finland, describe them as 'ecosystem engineers' because their dam-building work has such a good effect on habitats.

***

"The researchers argue that promoting facilitative ecosystem engineering by beavers could be very valuable in habitat conservation or restoration, especially in landscapes deficient in wetlands.

"The team set up camera traps and looked at tracks in southern Finland where the American beaver was introduced in the 1950s.

"After analysing the footage they compared the composition of mammal fauna of 10 beaver-modified sites with 10 control sites.

"The tracks showed that moose, otters, weasels and pine martens were more active in beaver patches than other sites.

"'The otter is a species of some concern in Europe, so this may be important from that point of view,' Petri Nummi at the University of Helsinki, Finland told the New Scientist.

"They found that water from the dams beavers build flood large areas, creating shallow ponds that harbour lots of invertebrates, like insects and crustaceans, the study said.

"The trees they fell create open spaces in the forest where young saplings can grow, they said.

"Felled trees, saplings and aquatic plants can all provide food for moose.
When beavers leave a pond and their dams break, the previously flooded area is rich in nutrients and can become a meadow.

"In forests where beavers have been introduced in Finland, their presence is linked to increased activity of several species, according to [the research]."

Comment: All part of the important balance of nature as created by God in his management of evolution. In my view humans were the goal of the creation of the entire process.

They eat microbes that help them use pollen:

https://www.scientificamerican.com/article/surprise-bees-need-meat/?utm_source=newslett...

"Bees are supreme pollinators because of what their babies eat. Most animals visit flowers to pilfer nectar, and they may or may not brush up against pollen and carry it to the next flower. Female bees, conversely, deliberately collect pollen, along with nectar, to feed their babes. This larval food choice is part of what defines a bee.

"Scientists have known for decades that fermenting microbes are present in pollen, but no one had seemed to consider whether they were also an important food for bees. The microbes function as an “external rumen” that breaks down parts of the pollen. It stands to reason that bees might ingest some microbes, but two researchers decided to investigate whether they eat enough to make them omnivores—and if the bees truly need those microbes to thrive.

***

"For most people, the idea that microorganisms can qualify as meat is radical. In the past four years, Steffan and his colleagues, including Dharampal, have published a series of papers laying out their evidence that microbes are an important part of a variety of food webs, including those that involve bees. Their findings confirm that fungi, bacteria and other microscopic players can fit anywhere in the food web, upending our vision of predator and prey, carnivore and herbivore—and what makes a bee a bee.

"Steffan and colleagues have also shown that microbial meat is a necessary part of bees’ diet. The researchers tested a species of mason bee that lays eggs in above ground tubes that are easy to access and transport. In each tube, the mason bee lays a series of eggs, each on its own wad of pollen and nectar. The researchers had a Utah beekeeper send them a batch of tubes immediately after the bees filled them. They then took the eggs off the wads and separated males from females, and used only the male bee larvae, divided into seven groups of 12. The scientists sterilized half the pollen and then fed different mixes of sterilized and unsterilized pollen to the groups. As the percentage of sterilized pollen in the food increased, so did the larvae’s likelihood of dying. The larvae also weighed less and took longer to mature. “Microbes are a very important source of nutrients for these bees,” Dharampal says. “If you take away this critical source, or portion, of their diet, they suffer tremendously.'”

Comment: Once again this study shows how the the econiche systems of the balance of nature are very complex and intricate and show why evolution had to develop such a huge diverse bush of life.

There is a complex of microbes, fungi and plant roots interacting through nutrients exchanges that is in the infancy of its scientific delineation:

https://www.quantamagazine.org/soils-microbial-market-shows-the-ruthless-side-of-forest...

"Beneath the green vegetable world we see is a dark microbial world we don’t. The crops we eat, the forests that sustain us and most other life forms, even the regulation of Earth’s climate — all benefit from a shadowy network of fungi and bacteria that mobilize soil nutrients and trade them with plants for sugars and fats. And yet the workings of this subterranean society are almost unknown to scientists. For example, researchers just mapped for the first time the global distribution of three major groups of these microbes. Even in 2019, what lies beneath our feet remains a true scientific frontier.

***

"Through innovative and groundbreaking studies, Kiers and her collaborators have gathered evidence that plants and their fungal conspirators are not just cooperating with each other but also engaging in a raucous and often cutthroat marketplace ruled by supply and demand, where everyone is out to get the best deal for themselves and their kind.

"Key to this picture is the revelation that the unseen underground world is just as complex, sophisticated and purposeful as the visible aboveground world we inhabit. Microbes are not simple, passive accessories to plants, but dynamic, powerful actors in their own right. Fungi can hoard nutrients, they can reward plants that are generous with their carbon reserves and punish ones that are stingy, and they can deftly move and trade resources to get the best “deal” for themselves in exchange.

***

"... tantalizing research hints at a capability that has been suspected but never proved: that fungi might not be just nutrient traders but also sophisticated information processors.
Kiers is the first to admit that scientists have far to go in puzzling out the hidden rules of the tiny networked organisms that somehow support all the rest of us. “Doesn’t it strike you as odd?” she said. “We know so much about other types of networks. This is undoubtedly the most important network for our ecosystems, but we just don’t know anything about it. … It’s radically under-studied.”

"When plants crept onto land some 500 million years ago, microbes were waiting. Fungi and bacteria struck up relationships with their new neighbors. Plants, after all, could do something most microbes could not: harness solar energy to split apart atmospheric carbon dioxide and construct energy-rich sugars and fats from the pieces. The microbes, in turn, had mastered the art of freeing up the nutrients that plants needed from the soil — phosphorus especially, but also nitrogen; there is evidence that microbes help plants gain access to water as well. Some 80 percent or more of today’s land plants form partnerships with fungi; still other plants partner with bacteria. If the soil were somehow purged of its microbes, the plant and animal worlds would take a big hit.

***

"Simard referred to forests as “supercooperators” and made the bold assertion that trees don’t just cooperate but communicate. She described birches and Douglas firs as engaging in a “lively two-way conversation” mediated by their underground collaborators. “I had found solid evidence of this massive belowground communications network,” she said, adding later in the talk, “Through back and forth conversations, they increase the resilience of the whole community.”

***

"But what really distinguishes the fungal world is its diversity and complexity. A spoonful of soil contains more microbial individuals than there are humans on Earth. “It’s the most species-dense habitat we have,” said Edith Hammer, a soil ecologist at Lund University in Sweden. A single plant might be swapping molecules with dozens of fungi — each of which might in turn be canoodling with an equal number of plants.

***

"Hammer reported evidence from experiments that fungi have a second trick: They can store nutrients when a plant isn’t paying well, withholding them until they get a better offer.
Together, the results turned scientists’ understanding of the plant-fungal relationship on its head. No longer could mycorrhizal fungi be seen as servants or passive accessories to their plant masters. Rather, life forms below the surface control their own fate, just as much as those above. It’s a dynamic marriage of equals."

Comment: Huge article barely touched upon. Key point: the entire Earth's life systems consist of these interlocking relationships at macroscopic or microscopic levels. Balances of nature are essential to the maintenance of living organisms. Individual systems may come and go over time as dhw notes, but at any given moment there must be necessary systems operating to support the life forms depending upon them.

A new study on deforestation and its bad effects:

https://www.theguardian.com/environment/2021/mar/24/disease-outbreaks-more-likely-in-de...

"Outbreaks of infectious diseases are more likely in areas of deforestation and monoculture plantations, according to a study that suggests epidemics are likely to increase as biodiversity declines.

***

"Even tree-planting can increase health risks to local human populations if it focuses too narrowly on a small number of species, as is often the case in commercial forests, the research found.

"The authors said this was because diseases are filtered and blocked by a range of predators and habitats in a healthy, biodiverse forest. When this is replaced by a palm oil plantation, soy fields or blocks of eucalyptus, the specialist species die off, leaving generalists such as rats and mosquitoes to thrive and spread pathogens across human and non-human habitats. The net result is a loss of natural disease regulation.

***

"The researchers examined the correlation between trends for forest cover, plantations, population and disease around the globe using statistics from international institutions such as the World Health Organization, the World Bank, the Food and Agricultural Organization and the Gideon epidemic database. Over the period of study from 1990 to 2016, this covered 3,884 outbreaks of 116 zoonotic diseases that crossed the species barrier and 1,996 outbreaks of 69 vector-borne infectious diseases, mostly carried by mosquitoes, ticks or flies.

"The paper shows outbreaks increased over time, while plantations expanded rapidly and overall forest cover declined gradually. By itself, a correlation is not proof of causality because other factors may be involved, such as climate disruption. The authors bolster their argument with multiple references to individual case studies that highlight the links between epidemics and land use change.

***

"The new study adds to a growing body of evidence that viruses are more likely to transfer to humans or animals if they live in or near human-disturbed ecosystems, such as recently cleared forests or swamps drained for farmland, mining projects or residential projects.

"This is shaped by trade patterns and consumer behaviour. A quarter of global forest loss is driven by the production of commodities such as beef, soy, palm oil and wood fibre. Mining adds to this problem by contaminating rivers and streams that are vital for a resilient ecosystem, carbon sequestration and soil quality.

"Morand said his study showed that disease risks needs to be added to risk-benefit analysis of new projects. “We should take the costs of public health into account when considering new plantations or mines. The risks are first to local people, but then worldwide because we have seen with Covid how quickly diseases can spread.'”

Comment: Same old point: all original ecosystems are exquisitely balanced. They should not be disturbed.

A new worrisome study:

https://www.quantamagazine.org/simpler-math-predicts-how-close-ecosystems-are-to-collap...

"....the tipping of ecosystems like forests and meadows is arguably harder to forecast because of the extraordinary complexity that comes with so many distinct interactions, said Tim Lenton, who works on climate tipping points at the University of Exeter in England.

"...interactions between species, which field ecologists dutifully record in their observations, can seem inconsequential, taken individually. In aggregate, however, they describe the detailed dynamics of the species interactions that make up an ecosystem.

"Those dynamics are critical. Many natural environments are incredibly complex systems wavering near a “tipping point” of nearly irreversible transition from one distinct state to another. Each disruptive shock — caused by wildfires, storms, pollution and deforestation but also by species loss — perturbs an ecosystem’s stability. Past the tipping point, recovery is often impossible.

"Understanding what determines these environmental tipping points and their timing is increasingly urgent. A widely cited 2022 study found that the Amazon rainforest is teetering on the edge of a transition into dry grassland, as deforestation and climate change make drought more frequent and severe over larger areas. The effects of that transition could ripple out globally to other ecosystems. (my bold)

***

"A recent breakthrough in the mathematical modeling of ecosystems could make it possible for the first time to estimate precisely how close ecosystems are to disastrous tipping points. The applicability of the discovery is still sharply limited, but Jianxi Gao, a network scientist at Rensselaer Polytechnic Institute who led the research, is hopeful that in time it will be possible for scientists and policymakers to identify the ecosystems most at risk and tailor interventions for them.

***

"Thousands of calculations may be needed to capture the distinctive interactions of every species in a system, Barabas said. The calculations make the models immensely complex, especially as the size of the ecosystem increases.

"Last August in Nature Ecology & Evolution, Gao and an international team of colleagues showed how to squish thousands of calculations into just one by collapsing all the interactions into a single weighted average. That simplification reduces the formidable complexity to just a handful of key drivers.

“'With one equation, we know everything,” Gao said. “Before, you have a feeling. Now you have a number.”

"Previous models that could tell whether an ecosystem might be in trouble relied on early warning signals, such as a decreasing recovery rate after a shock. But early warning signals can give only a general sense that an ecosystem is approaching the edge of a cliff, said Egbert van Nes, an ecologist at Wageningen University in the Netherlands who specializes in mathematical models. The new equation from Gao and his colleagues uses early warning signals too, but it can tell exactly how close ecosystems are to tipping.

"Even two ecosystems showing the same warning signals, however, are not necessarily equally close to the brink of collapse. Gao’s team therefore also developed a scaling factor that allows better comparisons.

***

"It took 10 years to develop this equation, Gao said, and it will take many more for the equations to accurately predict outcomes for real-world ecosystems — years that are precious because the need for interventions seems pressing. But he isn’t disheartened, perhaps because, as Barabas noted, even foundational models that provide a proof of concept or a simple illustration of an idea can be useful. “By making it easier to analyze certain types of models … they can help even if they are not used to make explicit predictions for real communities,” Barabas said."

Comment: the thrust of this article is an excited interest in protecting ecosystems. dhw refers to them as our food and constantly tries to diminish their importance. They were a major aspect of evolution, evolving as animals and plants evolved.