Inside Biodiversity

Not every species introduced by humans becomes a problem – but some do, especially on islands. In this episode of Inside Biodiversity, invasion biologist Marten Winter (iDiv and Leipzig University) explains how we define alien vs. invasive alien species, why the raccoon is a management challenge for Europe, and why management is particularly tricky in places like Australia. We also discuss the ethical dilemmas of controlling species such as the red fox – and whether it is possible to identify non-native species without knowing their origin.

What should we really aim for in nature conservation—and who gets to decide?
In this episode of Inside Biodiversity, science writer Emma Marris challenges long-held ideas about wilderness, ecosystem integrity, and invasive species. She argues that conservation is driven by human values—not objective science—and calls for a more democratic, transparent approach to setting goals for nature. If you’ve ever wondered whether “naturalness” is an illusion or why change in ecosystems isn’t always a loss, this thought-provoking conversation will make you see biodiversity in a whole new light.

Why has biodiversity decreased over the past 20 million years? Why did large mammals, such as giant sloths, tapirs, and mammoths, go extinct at the end of the last ice age, some 50,000 to 10,000 years ago? Why are there many fewer mammal species today than there “should be”?
In this episode, we speak with Prof. Susanne Fritz, research group head at iDiv and the Friedrich Schiller University Jena, about biodiversity change over very long time scales. She shares insights into how past extinction events shaped today’s ecosystems — and what that might mean for the future.

While some biodiversity change trends are deeply worrying, such as the decline of common bird species in North America, others offer hope, such as the recovery of rare birds: “I've seen in my lifetime species that were locally extinct come back, and rivers that were dead come back to life,” says Inside Biodiversity guest Henrique Pereira. “And that's because there's been so much positive development from environmental policy in Europe and in other countries in the world.”