you can *not* do that with even two versions of the same linux distro a year apart from eachother.
Hyperbole. Of course you can, if you design the software to handle that. One of my employer's pieces of software is compiled on SLES10 (from 2006) and runs on current Linux distros without a hitch. Code from 5 years ago compiled with gcc 2.95, and I'm sure that I could have that running both on a Linux release from 2000 and one from 2014.
Now, if you've got a programmer that doesn't have that as their specific goal in how they compile and package the software, then there will be a problem. With non-commercial software that's distributed by the developer as source anyhow, what's the reason for them to take enough care in packaging it to support forward-compatibility? If their software is popular enough, they know it'll be recompiled for inclusion in every new distro's repository anyhow, so they won't focus on supporting the goal of wide compatibility of the binary.
All megafauna is intelligent or it wouldn't have made it this long.
All megafauna have a combination of adaptive traits for their environment, some of which may be traits that we'd categorize under "intelligence". Intelligence isn't a scalar value. We might be able to measure its components by providing tasks that measure the presence and efficiency of specific capabilities of the brain and call the geometric distance from the 0-point "intelligence", but different animals will fall within different places in that multi-dimensional space. Some animals will have better scores than humans, in some dimensions. I'd posit that humans would have the greatest geometric distance from "0", though.
That's why I've never understood why some men whine about "always having to make the first move." It puts us in the driver's seat.
I used to complain about it because I didn't want to be in the driver's seat all the time. I wanted women to approach me as often as I approached them. That's still what I'd want out of dating.
I've never understood why some men want control all of the time. Give it a rest every now and then.
Two can Live as Cheaply as One for Half as Long. -- Howard Kandel