SPEAKER: So today I'm going to be talking about the way that different insect species are being threatened. In other words, the reasons why some insect populations are declining and might even become extinct in the 21st century. I'll also talk about the consequences if extinction occurs and some possible ways to prevent that.
Let's start with the reasons. First of all, when we look at what's going on in Europe, we can see a huge decline in certain species of insect. This is partly because farmers no longer allow certain plants to grow in their fields. But farmers are not entirely to blame. 1The gardens that people have nowadays don't always contain the kind of plant that insects need. So perhaps we need to rethink what we're putting there.
In more tropical regions of the world, for example, the Amazon rainforest, scientists have noticed that the number of beetle and butterfly species also appears to be diminishing. 2They put this down to climate change rather than, say, the fragmentation of habitat. But more research has to be done.
And then, there's the use of pesticides, and of course, this happens everywhere in the world. Pesticide is designed to kill a range of insects that farmers don't like. But it also kills bees, which they need. Pesticide might not kill bees directly, but we know that it impacts on their spatial skills, meaning they cannot make sense of what they see around them 3and also their memory. This means that they cannot remember how to get back to their hive.
So why worry about whether insects become extinct? Well, the consequences would obviously be terrible, not just for them, but for us. Pretty much everywhere on the planet. With the exception of Antarctica, 4insects are at the bottom of the food chain. They're absolutely vital, because if there were no insects, there would also be no birds or lizards or mammals.
Then there's the role that insects play in crop production. We use them to pollinate our fruit and vegetables, and it would be impossible to manage without them. It's also worth remembering that scientists are now studying plants to find out whether they might be a 5source of medicine in the future. If these plants disappear because of insect extinction, that would be another lost opportunity.
So there's some possible ways we could prevent insect extinction, some more controversial than others. I think it's a given that governments have to do something about the sale of pesticides. In fact, some countries have already passed laws to ban certain products. That's a good move forward. But ordinary people can also make a difference 6if we cut down on how much meat we ate, some of the land now used for grazing could be turned back into insect friendly environments.
I'd like to finish with a positive story. There's a place in California called the Antioch Dunes. In the 1900s, people looked at the dunes and the sands that formed them and thought that sound is a great raw material. 7And because they needed to build houses, they removed tons and tons of the sand and turned it into bricks. It wasn't really until the 1960s that biologists suddenly realized that the Antioch Dunes that'd actually been home to some unique species of plant and insect.
But by this time, there was only one species of butterfly left, the metal mark butterfly. And a major problem for the metal mark was that it required a certain plant to survive something called the naked stem buckwheat. 8It was on this plant that it laid its eggs. So, yes, you can see why the buckwheat was important. Well, in the end, the only way that the biologists could get the buckwheat to start growing properly was to replace the sand. That was a great first step. But the metal mark butterfly is still endangered.
9In the last decade, a significant number of butterflies and plants have been destroyed in the Antioch Dunes by fire. So now the biologists are limiting the number of visitors who can wander around the dunes. That's fair enough, I think.
All right. The final point I want to make about the project to restore the Antioch Dunes area is to do with how much land is required. When we think about the concept of conservation, we often assume we need to set aside a large amount of it. And that might be true for some large species. 10But in this case, relatively little land was required. But the important thing is to leave it undisturbed.
Okay, now what I want to talk about....
