this video is good simple(ish) explaination - note it says bacteria, but the vid is for most things that are invasive https://www.youtube.com/watch?v=zQGOcOUBi

this video is good simple(ish) explaination - note it says bacteria, but the vid is for most things that are invasive https://www.youtube.com/watch?v=zQGOcOUBi6s&list=PLsboZGJ1JMt96HDOL4_4dVf-RIQsZGZAO https://www.youtube.com/watch?v=zQGOcOUBi6s&list=PLsboZGJ1JM... It's from the Kurzgesagt – In a Nutshell channel