
Is it really possible to assign a dollar value to nature? It can't be easy to quantify the contributions that ecosystems and wildlife make to our economy, but more and more people are trying... hopefully that means more and more people are listening to the messages of conservationists.

Non-native species, whether they're introduced intentionally or by accident, can wreak havoc on local ecosystems and economies. Some say it's the single most costly environmental disruption to the global economy, with estimates of up to $1.4 trillion a year. Who are these animals and where have they come from?

It's not just environmentalists anymore who are concerned about nature. The business community is increasingly looking to invest in species and habitat conservation, recognizing that nature offers resources and services that are worth more to us than destroyed ecosystems are.

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