When an animal species disappears at the other end of the world – how much do we notice it here at home? Very! The scientists Frauke Fischer and Hilke Oberhansberg explain why.
BRIGITTE: So far the bee has been the symbol for species protection. Why did you choose in your book “What has the mosquito ever done for us?” now decided for this unpopular animal of all places?
Frauke Fischer: In the case of mosquitoes, the connection to our life can be clearly demonstrated: Mosquitoes are the only pollinators of cocoa. Without a mosquito there would be no chocolate for all of us.
Okay, convinced …
Hilke Oberhansberg: And that’s not all. To see the importance of a species, one has to look at the complex web of life – our World Wide Web of Life – that is related to the animal. Mosquitoes are also food for songbirds. Songbirds are important for the human psyche, they lower the stress level, which in turn has an impact on cardiovascular diseases. Entire ecosystems and our own survival depend on the preservation of a species – that’s what it’s all about.
How many animal and plant species are there currently? And how many have already died out?
Fisherman: It’s crazy how little we have to date about complete ecosystems and their services. We humans do not really know how many animal and plant species there are on earth. Maybe nine or 15 million. Maybe ten trillion.
Why is that?
Fisherman: If you ask children what they want to be later, they are more likely to say pilot: in or football star as a specialist: in for ants. In the area of species knowledge, there is only very limited training available today. With everyone who dies in this professional group, you usually lose a lot of knowledge. It’s like a library that burns down. In addition, many animal and plant species live in ecosystems where there are hardly any people – for example in the deep sea or in rainforests.
And even if we don’t live there, are we already destroying it?
Oberhansberg: I agree. Today, pollutants from outdoor textiles can be found, for example, in very remote mountain regions, in the air and in wastewater. You have to imagine this! Poisoned water, poisoned air, poisoned soils. People ensure that on average we lose one or two species an hour – most of which we don’t even know.
But why is it really bad for me when an animal that I don’t know dies on the other side of the world?
Fisherman: The endangered sea otter is a good example: sea otters eat sea urchins. This is important because otherwise sea urchins would destroy the seaweed underwater. But seaweed is important, there are entire underwater kelp forests off the coast of North America and they bind an incredible amount of CO2. In other words, if the sea otter dies, it not only makes the world poorer, it also increases the CO2 problem.
Oberhansberg: Another example is forests in the Congo, where animals and plants are connected in healthy ecosystems. And with all this diversity, the rainforest stabilizes our climate, also here in Germany, by binding large amounts of CO2. The less rainforest, the faster the earth heats up and the more extreme weather there is. If cars and houses are not to be washed away in Germany in the future, we must all have an interest in preventing the Congo from being deforested any further!
Back to Germany: Where are we making the biggest mistakes in terms of biodiversity?
Oberhansberg: Industrial agriculture destroys biodiversity with its heavy machinery, pesticides and fertilizers. This in turn means that entire ecosystems such as our soils are at risk.
That means in concrete terms?
Fisherman: Soils provide a unique ecosystem service. All human nutrition, apart from marine fish, is based on the performance of fertile soils: cereals, corn, rice. However, we are currently losing almost 3.5 tons of fertile soil per person in the world. At the same time, we are unable to produce fertile soil ourselves. So this is a huge problem. We often do not notice it in everyday life, but we are all already paying for this destruction now.
What do you mean?
Fisherman: The fewer insects we have through the use of pesticides, the less fruit is pollinated. The harvest yields decrease, as a result the same fruit and, for example, jam become more expensive.
Yes, that makes it less abstract.
Fisherman: There are also emotional reasons to preserve biodiversity. If man can choose, everyone would rather be in nature than in the middle of a motorway junction. And if we look at it from the ethical side: Is there a right to destroy everything that does not seem useful at first? Probably not.
What can each of us do specifically to prevent all of this? Buy organic, eat less meat – of course. What else?
Fisherman: Wondering which bank will get your money. Conventional banks often invest in environmentally harmful projects. Plant wild, insect-friendly gardens, not bare lawns, and build birdhouses – and not just in winter.
Do the consumers have the greater leverage here, or is it politics?
Oberhansberg: We are all asked. But industry and politics have a bigger impact. As soon as we can better quantify ecosystem services, i.e. give them a concrete value, they will influence political and economic decisions.
Do you think that would change our society in the long term?
Fisherman: There is a great social acceptance for the good. It is very likely that things like vandalism or aggression would decrease in the cities if they were more people-friendly and nature-friendly. Such a transformation increases our quality of life. We have to do away with the separation between humans and nature. Biodiversity determines the quality of life of every individual.
Biologist Frauke Fischer (left) and economist Hilke Oberhansberg recreate the relationship to our everyday life in a terrifyingly impressive way when species are extinct: “What has the mosquito ever done for us?” (224 pp., 20 euros, oekom).
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