As far as we know, planet earth has experienced five mass extinctions so far. The most recent of these, the Cretaceous–Paleogene extinction, happened around 65 million years ago and was responsible for killing off the dinosaurs. Mass extinctions typically come about because of catastrophic natural disasters, such as an asteroid impact, volcano eruption or sudden changes in sea level as a result of glaciation.
Asteroids pose no imminent threat, but we are losing species at an alarming speed. As Yago Partal wrote in his article on Biodiversity and Extinction, approximately 150 species of plant, insect, bird and mammal go extinct every day. If that sounds like a lot, it’s because it is! In fact, according to the International Union for Conservation of Nature (IUCN), we are now losing animal species at more than 1,000 times the normal rate.
Given these figures it’s no surprise that scientists are warning of a 6th mass extinction: the Holocene extinction. Unlike the previous five, what we’re now facing is both global and man-made. This is especially relevant this week, in light of a certain president’s decision to withdraw from the Paris Accord, the world’s first comprehensive climate agreement.
Protecting threatened species
For many, conservation is an emotional issue. Speaking on the BBC’s Life Scientific programme, conservation biologist Georgina Mace explains that people feel a connection to certain species. Unsurprisingly, these tend to be the more charismatic members of the animal world, often mammals like the giant panda or polar bear.
Prof. Mace was fundamental in developing the IUCN Red List, a global approach for evaluating the conservation status of flora and fauna. Although it is far from complete, the function of the Red List goes beyond documenting the bleak trend of extinction. It aims to identify species at risk of over-hunting and exploitation, so that efforts can be made to protect them.
She also suggests that it may be time to start looking across species more equitably, rather than focusing our attention on these more iconic animals. Every species has its unique value. With every animal that is lost, millennia of biological heritage goes with it. That said, some species are arguably more instrumental in maintaining a healthy ecosystem.
Global issue, global action
We’ve established that maintaining biodiversity is a global issue. It’s also evident now that human activity is the main cause of the recent acceleration in the extinction of plant and animal species. Some interventions that target specific threats, such as hunting and the illegal trade of wild animals, have been successful and population numbers have stabilised. However, if we are to stem the loss of biodiversity, the approach must be both micro and macro, local and global. This means not only tackling issues that affect individual species, charismatic or otherwise, but also the underlying factors that potentially threaten all life, such as climate change.
As author and geologist, Mark Williams, puts it: “there is no point in apportioning blame for what is happening; rather we have to recognise that our impact is game-changing on this planet and that we are all responsible.”