Alex McColgan

Life As of yet, there is only one example we know of, the life we find here on Earth.

There is no definitive proof of life anywhere else in the universe, but that does not mean for certain that it's not out there.

If there is alien life on planets other than our own, what might they look like?

What would be their biology, and what would we see of their civilization?

You might think there is no way to predict this.

However, believe it or not, even though we have never seen a single alien, we can make educated guesses based in science to help us know what to expect.

And it's all thanks to a simple principle.

Form follows function.

I'm Alex McColgan, and you're watching Astrum.

And although we cannot say with exact certainty what any aliens visiting us might appear like, or how they behave culturally and technologically, today I'm going to share with you some ideas that might mean, if they ever do land on our doorstep, you aren't completely caught off guard.

But first, let's talk about why we look the way we do.

As you look down at your own body, even if you do not know what all of it does, you are an incredible example of optimization.

You likely have two hands complete with fingers and opposable thumbs, ideal for grasping tools and performing fiddly, delicate operations.

You have a digestive system that is capable of taking in matter, extracting nutrients, and using them to build up or repair yourself.

You have legs for locomotion, a brain for thinking,

A heart that will, on average, pump 2.5 billion times across your lifetime without breaking.

All of these parts of your body perform specific functions, and have been honed over millennia to be really good at what they do, even if you don't feel it sometimes.

You are an example of form following function.

Thanks to natural selection and random mutation, nature is really good at figuring out what works.

When Charles Darwin was voyaging through the Galapagos Islands, he noticed that different finches had different shaped beaks.