No one can be sure it isn’t because people never see the consequences of even minor ecological changes so we don’t know in advance which animal, fish, or plant extinction will destroy a vital human resource.
1,000,000 plant and animal species are currently endangered and could soon become globally extinct, not just gone from some particular area and capable of repopulation such as Yellowstone bison/buffalo.
But much worse, the extinction of a single species often has a severe impact on the entire ecosystem, as all species are interconnected and rely on each other for food, habitat, and other resources.
This is because ecosystems are complex networks, where each species plays a unique role. When a species goes extinct, it can disrupt the flow of energy and matter through the ecosystem, and can also leave other species without essential resources or protection.
Extinction of a keystone predator
For example, the extinction of a keystone predator, such as the wolf, can lead to the overpopulation of its prey, such as deer. This inevitably leads to a cascading effect on the entire ecosystem, as the deer overgraze vegetation, which can lead to erosion, soil compaction, and the decline of other plant and animal species.
Extinction of a pollinator
Similarly, the extinction of a pollinator species, such as the honeybee, can lead to the decline of the plants that rely on that species for pollination. This can have a negative impact on the entire food chain, as many other animals rely on those plants for food.
Wiping out even a seemingly insignificant species has a ripple effect throughout the ecosystem. For example, the extinction of the dung beetle, which helps to break down manure, can lead to the accumulation of manure, which can pollute water supplies and spread diseases.
In today’s world, human activities are driving the extinction of species at an unprecedented rate. Habitat loss, pollution, climate change, and overexploitation are all major threats to biodiversity.
One Extinction leads to others
When a species goes extinct, we lose not only that species itself, but also all of the ecological roles that it played in the ecosystem. This can have a devastating impact on the entire ecosystem, and can also make it more vulnerable to other disturbances.
It is therefore essential that we take action to protect biodiversity and prevent extinctions. This means reducing our impact on the environment, conserving habitats, and managing resources sustainably.
Extinction can have a cascading effect on ecosystems, leading to the decline of other species.
For example, if a predator species goes extinct, its prey species may overpopulate and overgraze vegetation, damaging the ecosystem. Or, if a pollinator species goes extinct, plants that rely on that pollinator may no longer be able to reproduce, leading to the decline of other species that depend on those plants for food or habitat.
The impact of extinction on other species can also be indirect. For example, if a species that provides important ecosystem safeguards, such as water filtration or carbon sequestration, goes extinct, other species in the ecosystem may suffer as a result.
Extinction – factors to consider.
The magnitude of the impact of extinction on other species depends on a number of factors, including:
The type of interaction between the extinct species and other species. Some interactions, such as predator-prey and pollinator-plant interactions, are more tightly linked than others. If an extinction event disrupts a tightly linked interaction, it is more likely to have a significant impact on other species.
The level of dependency on that interaction is important to know. Some species are more dependent on certain interactions than others. For example, a specialist pollinator species that only pollinates a single plant species is more dependent on that interaction than a generalist pollinator species that pollinates a variety of plant species. If an extinction event disrupts an interaction that a species is highly dependent on, it is more likely to have a significant impact on that species.
The availability of alternatives. If there are other species that can fill the same ecological niche as the extinct species, the impact of the extinction may be less severe than if there are no alternatives.
In general, the more tightly linked an interaction is, the more dependent a species is on that interaction, and the fewer alternatives there are available, the greater the impact of an extinction event is likely to be on other species.
Extinction – read on for some specific examples.
Here are examples of a cascading extinction event:
The Tasmanian tiger (Thylacinus cynocephalus) was a marsupial predator that went extinct in the early 20th century.
The Tasmanian tiger preyed on the red-necked wallaby (Macropus rufogriseus).
After the Tasmanian tiger went extinct, the red-necked wallaby population exploded.
The red-necked wallaby overgrazed the vegetation, which led to soil erosion and habitat loss for other species.
As a result, many other species in the Tasmanian ecosystem declined, including the eastern quoll (Dasyurus viverrinus) and the Tasmanian bettong (Bettongia gaimardi).
Wiping out the passenger pigeon led to the decline of many other species of birds, insects, and plants that relied on the pigeon for food or habitat.
The extinction of the Tasmanian tiger led to the overpopulation of kangaroos and other prey animals, which caused damage to the environment and led to the decline of other plant and animal species.
The extinction of the Hawaiian honeycreeper led to the decline of many plant species that the honeycreeper pollinated.
The extinction of the white rhinoceros is likely to lead to the spread of invasive plant species that the rhinoceros helped to control.
This isn’t something we can safely ignore because these examples show how the extinction of a single, let alone one million species has a critical and dangerous effect on an entire ecosystem.
My own book written almost decade ago which predicted the obvious truth that there would be no government action on the environment. “Preparing for Climate Change: Coastal flooding will cost the U.S. billions of dollars within two decades.”
Paperback second edition
Editor’s Note: Author used Google BARD to locate appropriate references from scientific bodies.
2023 state of the climate report: Entering uncharted territory | BioScience | Oxford Academic (oup.com)
Earth Has Crossed Several ‘Planetary Boundaries,’ Thresholds of Human-Induced Environmental Changes | Scripps Institution of Oceanography (ucsd.edu)
Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) Earth Has Crossed Several ‘Planetary Boundaries,’ Thresholds of Human-Induced Environmental Changes | Scripps Institution of Oceanography (ucsd.edu)