From said article:
There is an argument that in places where truly wild horses once existed, feral horses perform the same ecosystem functions. This is a complicated argument in lots of ways, as when rewilding an area how far back can we go? Is the modern horse a suitable candidate in America, given the evolved there, went extinct, and then were reintroduced by Europeans?This is maybe a complicated argument but an important one. The modern world is one where biodiversity is unusually low. North America lost a lot of its megafauna at the end of the last ice age, presumably with human help. The most notable exception were bison, which were systematically cleared out by American settlers.
These animals didn’t live in isolation, they were part of ecosystems with other species that depended on them. Some plants largely relied on them for seed distribution and while the original megafauna that played those roles are gone, many have done better where horses and cattle have stepped into similar ones. It’s less well-studied but it is suspected that other things, like for instance the whole world of dung-feeding invertebrates, may be similar.
To the point where some have advocated for Pleistocene rewilding, introducing African megafauna to try to fill the missing ecological niches. That’s a very extreme position of course and not too many people would agree with it. But I do think it is an example of how things are not so simple as native = good, introduced = bad when it comes to conservation and holding onto what diversity we can. Horses both are and aren’t supposed to be part of the environment here, and can both help and harm accordingly.
