Spreading a Little Unhappiness

We humans have proved very effective at moving viruses, bacteria, fungi, plants and animals around the globe. Some of that movement has been deliberate and some accidental/careless. It's been estimated that currently at least 37,000 species of fungi, plants and animals have arrived, with human help, in 'problematic' locations. About 200 new alien species establish themselves each year. The whole topic of invasive species is, however, under-appreciated; under-acknowledged and under-reported (https://www.theguardian.com/environment/2023/sep/04/invasive-species-cost-humans-423bn-each-year-and-threaten-worlds-diversity-aoe). It's been estimated that around 3,500 invasive species cause major, widespread problems. Species become invasive when they outcompete local variants and/or find themselves in locations without their natural controllers (e.g. consumers, predators or parasites etc.). Invasives often have a devastating effect on biodiversity, especially in formerly geographically-isolated areas. Invasive species are collectively costing humans over $420 billion per year. It's no small problem.