The Biodiversity Crisis
“Biodiversity” visualised in a museum, by Dom Dada.
Scientists are calling the current period the 6th mass extinction event in Earth’s history, or “The Biodiversity Crisis”. Biodiversity is commonly measured by the number of different species in a given area. Global biodiversity loss is accelerating at a truly staggering rate. Current estimates place the extinction rate of all species at 1000 times the background rate that has been occurring over the past 10 million years, with approximately 1 million species currently at risk of extinction.
In some cases, the removal of one species can be accounted for by increases in another species. However, many species play important “functional roles” in ecosystems that are critical to normal processes. These may include pollinators or top predators, or even more foundational species: e.g., the great barrier reef can’t survive without coral and the amazon is nothing without trees!
Why is this a problem?
There is an intrinsic value argument for minimising biodiversity loss, i.e. that the natural world is a thing of beauty, and that alone means we should do everything we can to preserve it. Similarly, one could argue from a philosophical perspective that we are the only species with the understanding and capability to preserve ecosystems and biodiversity, and therefore have a moral obligation to minimise damage. However, there are many more tangible reasons why we need to maintain healthy ecosystems. Many of us think of the “environment” as separate from the human world and our society. This is especially true if you live in a major city in which the urban environment is the only landscape you experience on a daily basis. However, even if we don’t like to admit it, we all rely on Earth’s natural processes and normally functioning ecosystems. This isn’t just for “greenies” or the occasional weekend camping trip. Healthy ecosystems provide sustainable food, breathable air, clean water, huge economic value, and regulate weather patterns.
For example, 75% of our agricultural crops rely on pollination from animals. Further, the efficiency of agriculture decreases as normal nutrient cycling is disrupted – a direct consequence of biodiversity loss. Similarly, 3.3 billion people rely on seafood as a protein source. Ecosystem collapse has significantly reduced the productivity of fisheries by limiting the total biomass of fish available for consumption.
The White Rhino.
There’s also a sense of “opportunity cost” that we never got to experience, interact with, or learn from extinct species. Beyond the sadness of never being able to see a northern white rhino or a Tasmanian tiger, there are countless examples of where we have learnt from studying animals. Over the course of millions of years of evolution, nature has developed truly astounding ways of solving problems far better than human technology can. We have modeled helicopters from hummingbirds, wind turbines from whale fins, anti-freeze from the blood of arctic fish, and microorganisms continue to be the number one source of new life-saving antibiotics. Who knows what secrets have been lost forever with extinct species.
The Tasmanian Tiger.
What is causing it?
Although extinctions have occurred throughout evolutionary history, the current rate is significantly faster and directly caused by human activity. You may think that species will come and go as they always have throughout history and this isn’t a big issue, but problems arise when the rate of extinction starts to increase rapidly. In previous mass extinctions, this has led to catastrophic re-structuring of Earth’s ecosystems. For example, during the Permian-Triassic extinction, over 90% of species were lost and it took at least 5 million years for highly productive ecosystems to return. Look around you: can you imagine if only 1 in 10 species continued to exist?
There are direct and indirect human causes of biodiversity loss. The direct causes tend to be the more obvious ones that we know of: e.g., mass land clearing of rainforest for agriculture and urban expansion, overfishing with improper management, excessive pollution, or trophy hunting of endangered species. Of these, land clearing is generally regarded as having the greatest impact on biodiversity. The indirect causes of biodiversity loss may be more insidious, for example, the warming effects of climate change pushing species out of suitable habitat, or the introduction of invasive species.
Land cleared for palm oil. “RAN’s Rainforest Agribusiness Team Investigates Palm Oil Controversy in Indonesia”.
While I know this has all seemed quite gloomy so far, there are a number of things we can do to help balance environmental protection and human welfare. I don’t believe it is helpful to give blanket rules like “stop eating seafood”. Yes, that will undoubtedly prevent overfishing, but for many people, it simply isn’t an option because their livelihood depends on catching fish, or seafood is their only source of protein. Besides, that demand for food will simply shift to land usage, so if we are employing inefficient agriculture, it just moves the problem to a different area. So, what can we do?
First and foremost, go out and enjoy nature. Besides the well-studied psychological and physical health benefits of being amongst nature, we are much more likely to want to protect ecosystems if we enjoy them. This is especially true for children; kids who grew up appreciating nature are much more likely to continue that trend throughout their adult lives.
Food choices are a large decision that can have an impact every day. We should follow evidence-based guidelines here to ensure our food production systems are sustainable. For seafood, this means choosing produce caught from sustainable fisheries – most developed countries have a governing body or not-for-profit that can provide you with basic information on which fish to choose (e.g. Australia: goodfish.org.au, afma.gov.au/species; UK: mcsuk.org; USA: fishwatch.gov). Not all species are created equal in terms of fishing sustainability. For example, orange roughy is a deep-sea fish that takes ~30 years before it will reproduce, and many shark and ray species will only produce one offspring every few years. In both these cases, it is very easy to overharvest and drive their populations into the ground – just like we saw with commercial whaling. Compare this to other species, like some snapper, in which females very rapidly reach sexual maturity and can produce over 1 million eggs each year!
Similarly, choosing highly efficient, regenerative agriculture processes can be important in reducing land clearing and thus help minimise biodiversity loss. Basic guidelines include minimising food waste and reducing meat consumption. If you have a backyard, consider growing your own vegetables. Besides the sense of accomplishment, you will feel, you’re actively reducing food mileage, and every patch of land you use to grow your own food is land that doesn’t have to be cleared for agriculture elsewhere.
More broadly, vote with your wallets and in elections for leaders who will make meaningful change in this space. Governments should be investing in technologies to enable more sustainable agricultural practices and renewable energy production. Environmental protection needs to be taken seriously as a political issue; the long-term costs (economic and otherwise) of non-action are orders of magnitude greater than implementing change today. We are seeing whole industries transform into more sustainable modes of operation simply because it makes economic sense to do so: over the next 5-10 years we will likely see electric cars take center stage as affordable, fun, and safe options with the massive additional benefit of not burning fossil fuels. Similarly, in my home country of Australia, we have a lot of sun! Solar panels on houses are common now because they provide clean, free energy – it’s really a no-brainer.
We are not separate from nature, and failure to manage this problem will lead to significant health and economic costs for us and future generations. Ultimately, there will need to be a combination of individual, institutional and government-led change to minimise biodiversity loss in the coming years.