We have only covered ~200ly with radio waves. That is a small spot in our galaxy, let alone universe. The core is ~25.000ly away. I think the original signal would be highly distorted by then. I still think seti@home was worth it, but it cannot answer the question about alien life negatively if it doesn't net a positive result.

True. I have always wondered why no other species on Earth have evolved in a way Humans have. Every other species maintains the balance in nature but we are the only species actively creating imbalance and destroying the planet. Prometheus might have been true after all.

All the species evolve the same way.

None of the species care about any specific "balance".

Humans are not destroying the planet (talk about hubris), but the biosphere and possibly the civilization.

I don't know about that. One species poisoned most other to death, a long time ago.

What species might that be?

There are five known big mass extinction events in Earth life history, the first one is caused by... drumroll... small plants. https://www.youtube.com/watch?v=mAkjETPM1s4

That lead me to this one, he's funny: https://www.youtube.com/watch?v=FlUes_NPa6M

That's because sooner or later every species enters an equilibrium state with the amount of energy available in the ecosystem. In the process it may out-compete quite a bit of other species, and so we speak of 'invasive species'.