Astronomers Detect a Possible Signature of Life on a Distant Planet

My greatest desire is to know why we don’t see any galaxy-sized colonies. A great filter would certainly be a fascinating response!

My guess is any civilisation advanced enough to populate their galaxy knows that it's inherently pointless. Unchecked growth is the impetus of lesser lifeforms

Life is probably extinguished by machine intelligence before it gets the chance to.

ALL of it? EVERY time? There should be some signs somewhere.

I mean, communication is insanely hard. If there's no way around the speed of light, life would still likely (slowly) expand across the stars, but it would be functionally impossible to continue to act as a unified civilization or colony across even a couple solar systems much less a whole galaxy

I find myself believing less in the great filter. My comment here: https://news.ycombinator.com/item?id=43712645 explains why.

One thing that I haven’t seen discussed much in terms of galactic colonization is genetic drift, speciation and communication.

I believe there are simulations theorizing that galaxies can be thoroughly explored in 10M - 100M years.

But how would those species even communicate their discoveries across a 100k LY galaxy? The delay would render data inaccurate by the time it arrives. It seems challenging to persist in a common purpose for millions of years across vast distances.

And would they even be the same species on those timescales and distances? On Earth isolation leads to some unique physical and cultural evolutions.

Maybe life already colonized everything within possible reach, made most of it inhospitable, and the remaining three survivor galactic empires sent an ark and some supplies to a small planet called Earth.