First, I have your Sense of Wonder right here: Multi-celled anoxic organisms: Animals that live without oxygen, discovered deep in the Mediterranean. They look like little anemones. Or little elongated jellyfish. Or little bottle brushes.
This is exciting, although I have trouble putting it into words why. It's just... neat, you know? Yet another different life form, yet another way in which life found a niche.
The nice thing about the development and spread of life is that once it starts, there's no stopping it short of planetary-scale disaster, and I don't mean piddly little disasters like global thermonuclear war or a little tiny bit of climate change. If things progress to Venus-level global warming, then we'll talk. Until then, life will find a way. (Human life is another matter.) Lifeforms vie with one another. Life itself has no rival, no competition---unlife does not propagate.
In other Sense of Wonder news, see if you can figure out what the little dot is before clicking on the picture and reading the explanation, assuming you did not see the picture before: