My reading material at the moment has some connection, albeit rather slight, with the squirrel. Otherlands by Thomas Halliday. Incredible that he is 20 years younger than I am and has fitted so much more into his life and into his head and onto the page. This is a remarkable book. It goes back in time, focusing on one location for each section.
I am already a long time ago, as it were, and at this point South America is an island but not quite as far from Africa as it is today. Turns out that some monkeys and amphibians made the Atlantic crossing from one continent to the other on rafts of trees washed down the African rivers and into the sea. The South American creatures, the ones who did evolve isolated there for longer, are completely different families but fill the same niches as the animals in Africa. Convergent evolution. So there are animals that fill a hare niche and an elephant niche, for example. There are many and varied ground-dwelling sloths.
One of the points Halliday makes is that the ideas of native species and invasive species are rather spurious. When do you date native from? How can you condemn an invader who never intended to go there and is just trying to survive? And how can you expect animals not to move when the records show that they crossed the Atlantic on a raft, surviving at least six weeks at sea??
He seems to suggest that what matters for the ecology is that there are creatures to fill niches, not who those creatures actually are - not in terms of species. In terms of ethics, then, we might say that individuals matter (they suffer or experience pleasure), while for ecology what matters is filling the niche - and whether that be red squirrel or grey squirrel is immaterial. Of course, that there is no creature filling the pine marten niche in most of the UK is a proble, But it's the ABSENCE that's a problem, not the presence. If you see what I mean.
We always seek to remove. We seem to be conditioned to eliminate, simplify and destroy rather than to enrich, add and generate. Apart from ourselves. We sure add ourselves. To bloody EVERYTHING.
Squirrels are so handsome. It's something to do with the glorious tail and those eyes!
I read the interview at the Otherlands. The book sounds good! I think he - and you - make about native vs introduced species is an impt. point in this age of rapid climatic changes and the vast amount of human interference.. And things have always been changing - always.