Life before us, life after us, life on other planets – we’ve explored what this might look like, both in reality and media. So what conclusions are we able to draw here?
What We Know
Yesterday: While extinct life might be far away from our documented history, there are a lot of things we can conclude about them from fossil findings. Diet, size, life cycle, habitat, all these can be inferred about from well-enough preserved fossils.
Tomorrow: Evolution is not a simple, easy process – it has no steady progression, happens rather in fits and starts. Life adapts where it can or just perishes. New species rise to the top while others quietly fade away.
Elsewhere: Despite the sheer vastness of the universe, earth-like planets are incredibly rare. So rare in fact, that we have yet to find a planet that would be suitable or even habitable for humans without artificial interference. And even if we would find a planet that’s technically habitable it’s not a guarantee for life. The conditions needed to form life might not be able to sustain it in the long-term.
What We Can Guess
Yesterday: Life doesn’t exist in a vacuum, it’s possible to draw conclusions about extinct animals when comparing them to ones currently alive. Similar features are likely to have served a similar purpose and can be studied today to find out more about what advantage they had in the past.
Tomorrow: It’s unlikely that us humans will ever undergo another major step in evolution. We’re too wide-spread, too robust to ever truly need to change. If anything, we will die out rather than change. Though this will not necessarily mean the end of life itself.
Elsewhere: Using earth as basis, we can infer what conditions are needed to support life. Conditions like the availability of water, energy and carbon are key to make a planet habitable. We can also draw conclusions about alien life using life on earth – if the nature of the universe is the same everywhere, life elsewhere should abide the same rules. This of course assumes that any planet with the ability to sustain life will contain it.
What We Make Up
Yesterday: Unfortunately, science can only bring us so far when it comes to reconstructing extinct animals. Body parts like soft tissue as well as integument, colouration rarely get preserved. Behaviour, too, will never be able to be predicted with absolute certainty. We might be able to fill in the blanks but will never know if we were right.
Tomorrow: We can’t know for sure who will come after us. Which species would survive the sixth extinction and become the next rulers of the world. Or if that will be a possibility at all, if earth will ever host intelligent life again or go back to being a savage planet.
Elsewhere: We should try not to fall into a human-centric view when making depictions of alien life – it might not look like anything we’re familiar with. Or anything we can even imagine.
