Many environmental science students are not always aware of the causes of this phenomenon.

When it comes to the causes of global biodiversity loss, there are clear differences in perception among students of environmental subjects around the world, as shown by a survey conducted by Goethe University Frankfurt among more than 4,000 students from 37 countries.

The gaps vary from country to country: in some countries, climate change is underestimated as a cause of biodiversity loss, in others it is invasive species, in others it is pollution. The survey also shows that country-specific indicators greatly influence students’ perceptions.

Of the estimated 10 million species of flora and fauna still on Earth, most of them still unknown, 1 million could disappear in the coming decades. This loss of biodiversity would have dramatic consequences, because animals and plants provide many services. They maintain ecosystems, ensure a more balanced climate on our planet and provide us with food and active substances for medicines. In short, without biodiversity, we humans will not survive.

This is why there is an urgent need for decisive political action to counter the “sixth mass extinction” in Earth’s history. Environmental science students are particularly important. Many of them will likely occupy influential positions in environmental policy and economics in the future, and will play a key role in combating the global decline in biodiversity.

But how knowledgeable are tomorrow’s decision-makers? Are they able to identify the main causes of biodiversity and distinguish them from factors that have no influence on biodiversity? “Our study is the first to examine these questions scientifically on a global scale,” says Dr. Matthias Kleespies from the Department of Biological Science Education at Goethe University Frankfurt.

The work is published in the journal Biodiversity npj.

Together with other researchers in Frankfurt, Kleespies conducted an online survey of 4,400 students from 37 countries enrolled in environmental studies. They were given a questionnaire listing eight drivers of global biodiversity loss. These drivers include the five real causes: climate change (increasing droughts and other consequences of global warming), overexploitation (such as overfishing), habitat loss (e.g. due to deforestation), displacement by invasive species, and pollution (air pollution, plastic waste, oil spills).

The questionnaire also listed three factors that have little or no impact on biodiversity: electrosmog, factory and traffic noise, and the Internet. Respondents were asked to indicate to what extent they thought these eight factors were responsible for the decline in biodiversity. The scale ranged from 1 (minor influence) to 5 (major influence).

To analyze the completed questionnaires, the researchers used a special method that recognizes patterns in the data. The result was eight different groups with specific and easily distinguishable clusters of response types.

Kleespies explains: “In response type 1, for example, all the main causes are recognised, with the exception of climate change. Students underestimate its influence on the decline in biodiversity.” In response type 2, on the other hand, pollution plays a secondary role, and in response type 7, invasive species. Response type 3 is a special form in which all the main causes are underestimated and are not even distinguished from irrelevant factors such as noise.

“Fortunately, the number of these responses is relatively small,” says Kleespies. Overall, the eight types of responses occur with varying frequencies across the countries studied.

In the next step of the assessment, the research team examined the context of the responses: what drives the different types of responses? Here, the researchers incorporated country-specific indicators: the country’s CO₂ emissions as well as indicators of prosperity, environment and biodiversity. Kleespies says: “We found that these indicators significantly influence students’ perceptions in the country concerned.”

In response type 1, for example, climate change is underestimated as a factor. In countries with very high CO emissions,₂ In countries with low emissions (such as Russia, China and Saudi Arabia), type 1 is much more common.

“Although our data cannot explain why this is, we suspect that students in these countries are less aware of this phenomenon. They are not taught at university that climate change also exacerbates biodiversity loss.” Moreover, it has to do with their own country’s contribution to climate change. Perhaps people are not as willing to admit the magnitude of this phenomenon.

In the case of response type 2 (pollution as an underestimated factor), a correlation between students’ perceptions and country-specific indicators can also be observed, but in a different form. In rich countries with healthier ecosystems (such as Australia, Sweden and Germany), students more often underestimate the pollution factor. Kleespies assumes that pollution is generally not perceived as a problem in these countries and is therefore not considered a major cause of global biodiversity loss.

Response type 7, which greatly underestimates the influence of invasive species, is more widespread in countries such as Nigeria and Kenya, where these species are less common. In Australia and Spain, on the other hand, type 7 is rare, although it is precisely in these countries where invasive species pose the greatest problem.

What conclusions does Kleespies draw from this study? “It shows for the first time the huge gaps in perception between the next generation of environmental decision-makers regarding biodiversity loss and its causes. We need to close these gaps.”

This is where today’s decision-makers in universities and politics come in. They must create the general framework so that all the causes of this complex problem are addressed in environmental studies at universities in their respective countries.

“Biodiversity loss affects us all; it is a global problem. That is why students in environmental studies programs need to think globally, regardless of their country of origin.” The study is a call to action in this regard.