Imagine going to a museum and seeing a display on ancient human ancestors.

These ancestors looked a lot like us, of course, but just a little different.

Their jaws were bigger and bulkier.

They had sloping foreheads and snub noses.

They were shorter and chaggier and hunched over, not quite comfortable yet on two feet.

Now imagine going to a museum in the remote future.

And imagine that the ancestors on display then are, well, us, you and me.

What traits about us would stand out to those future humans?

That depends, of course, on how human beings evolve and change in the future.

And while that's impossible to predict completely, scientists do know of certain factors that

drive animal evolution.

One big one is climate.

That is, when climates change, animal bodies change in predictable ways in response.

Depending on the details, the animals might get bigger or smaller, or have their appendages

change size.

And of course, Earth is now entering a period of unusually fast global warming.

So in today's episode, I'd like to try a little thought experiment.

Let's say we hit pause on modern technology.

But as let's put aside the possibility that humans in the future might actively engineer

our DNA, let's also say that climate change continues and that Earth grows much warmer.

How would that new climate remake the human body?

As we'll see, some of the predictions in play are controversial, but they're nevertheless

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