In 2019, the Sumatran Rhino was declared critically endangered. Also known as the ‘hairy rhino’ it is the smallest species and, like both African species of rhinoceros, it has two horns. They now number less than 80, making the species another victim of the 21st century.
Some question this conclusion. They point to the fact that animals always become extinct, so why is this different? Is it simply time for the Sumatran Rhino to go the way of the Dodo and the Golden Frog?
This is an understandable and tempting viewpoint. After all, if something is sure to happen, no matter what, then why bother trying to prevent it? Why don’t you sit back, make yourself a drink and save your energy. However, this attitude misses a key aspect of the problem and risks sleepwalking into a mass extinction event
Past Mass Extinction Events
Animals do naturally become extinct. Although extinctions continually happen, there have been five periods of mass extinctions. The most recent was 66 million years ago when earth was likely hit by an asteroid, famously killing the dinosaurs. Other mass extinction events were caused by natural changes in the climate like global cooling and global warming.
When scientists talk of a sixth mass extinction, one may wonder why it is any different to the last five. It may feel like fighting this mass extinction opposes nature. However, this time nature has little to do with it. Fossil records point to the fact that extinction is occurring now at 1,000 times the background rate. This means that without any interference, the ‘natural’ process of extinction would be 1,000 times slower than it is right now. Extinction is natural, but extinction at this rate is not.
The key factor this time around is not an asteroid, natural changes in global temperatures or volcanic eruptions. No, the cause of this potential mass extinction is us.
Human beings are the dominant species on this planet. We live in every continent except Antarctica and even there you can find 1,000 humans or so throughout the year. The impact of our presence is equally vast, harming biodiversity and the long-term prospects of species across the globe. (Biodiversity refers to the variety of plants and animals in any environment. Biodiversity is highly desirable). Here are the main ways that modern human habits are harming biodiversity and heralding a sixth extinction.
Climate Change and Pollution
What was once a controversial statement is now agreed among scientists: our climate is changing dramatically and quickly. By burning fossil fuels that release harmful gases into the atmosphere and by cutting down trees that absorb harmful gases, humans are the main drivers of climate change.
A stable ecosystem relies on balance and the changing climate is disrupting that balance. As a result, animals from the smallest insects to the biggest land and marine mammals are at risk from the changing climate.
Cutting down trees not only increases carbon dioxide in the atmosphere, but it also destroys millions of acres of habitat for local animal populations. From the very beginning of the global warming process, animals have been suffering.
The warming temperature affects the Arctic at almost twice the rate of the global average, melting huge amounts of ice cover. Many animals rely on this land area for survival and its reduction threatens extinction for many species. Polar Bears are projected to be extinct in the Arctic region by 2100.
The melting of ice sheets and glaciers will raise sea levels, which threatens an uncountable number of coastal animals and plants. This is a direct threat to biodiversity.
Sea levels are not only rising, but oceans are getting warmer, more acidic and more stormy. All three of these changes are a risk to the biodiversity of our oceans.
Marine life relies on predictable temperatures to live and reproduce, causing mass migration and disrupting the food chain. Coral bleaching is also made worse by increased water temperatures.
Increased acidity threatens many species, especially those who rely on building shells (such as lobsters and scallops). It also makes it harder for coral reefs to recover from bleaching.
Increased storms lead to more floods and then more polluted water, creating ‘dead zones’ as well as damaging coasting regions.
Not to mention the plastic crisis in our oceans, which could leave us with more plastic than fish by 2050.
This is only a whistle-stop tour of the ways that climate change is damaging biodiversity.
Overexploitation, or overharvesting, happens when humans make excessive use of a resource, more than its natural replacement rate. Humans hunting and exploiting wildlife to extinction is not a new problem. As early as 10,000 years ago there is evidence that mammals such as mammoths and mastodons were driven to extinction partly by overhunting. In modern times, the problem has begun to get out of control. Some studies suggest that the overexploitation of wild animals is the leading driver of biodiversity loss.
An international committee for biodiversity (ipbes.net), that has 132 countries as members, found that the most overexploited species worldwide are ‘marine fish, invertebrates, trees, tropical vertebrates hunted for bushmeat and species harvested for the medicinal and pet trade’. If you add poaching and trophy hunting into this equation, you have a wide-ranging problem of the exploitation of animals and plants of every size.
Additionally, recent human overpopulation has increased our invasion into natural habitats, as ecosystems are destroyed and natural resources are polluted to build houses. This results in the local animal populations suffering and their numbers decreasing.
Agriculture emits 9.9% of greenhouse gas emissions and causes a whopping 70% of deforestation. Animal agriculture is the biggest culprit, accounting for 80% of agriculture’s impact. These figures make it clear that agriculture, primarily animal based, is a big driver of climate change, which is a primary driver of biodiversity loss.
The aspect of the agricultural industry that often gets ignored is how it contributes to habitat destruction. The WWF estimate that 60% of global biodiversity loss is a result of meat consumption. As the livestock industry uses around a third of the Earth’s land, many natural habitats that could support a diverse range of animals have been destroyed in the name of animal agriculture.
Experts suggest that if everyone had a diet of mainly plants, this would free millions of acres of land with the potential for rewilding, as well as protecting habitats from further destruction.
An invasive species is one that enters a new environment and has a negative impact on other organisms. In the last two centuries, the number of invasive species has increased, with the highest increases in recent decades. The climate crisis, tourism, transport, the pet trade and many other human activities are the primary causes of invasive species. Ask any Aussie about the cane toad or any rural Brit about the grey squirrel and the fury you receive will give you an idea of how destructive an invasive species can be.
Why it matters
Biodiversity matters because having a varied planet populated by beautiful and unique animals is one of the wonders of life. But that is not the only reason. Biodiversity is also key for humans. As they sum it up at The Conversation, ‘Without these organisms, ecosystems and ecological processes, human societies could not exist. They supply us with oxygen and clean water. They cycle carbon and fix nutrients. They enable plants to grow and therefore to feed us, keep pest species and diseases in check and help protect against flooding and regulate the climate’.
In short, by reducing biodiversity we are harming animals and ourselves.
The Bad News and the Good News
The bad news is that the biodiversity problem is real and it is a direct threat to animals and humans flourishing on this planet. It cannot be ignored, and saying that it is inevitable risks giving you and earful of sand… you know, like an ostrich.
The good news is that because the problem is human caused, it can be human solved. This is why biodiversity loss is a pressing problem and conservation is a vital cause. We can prevent further biodiversity loss and build a better planet together.
By Zachary Reeve
Zachary is an English literature graduate who loves writing, reading, watching films and learning about all things language. More than anything, he is dedicated to protecting the environment and preserving biodiversity.
Zachary writes The Blog Thickens https://theblogthickens.com