How did Steve Rogers go from being a mild-mannered, scrawny soldier to being the muscle-bound leader of the Avengers? More importantly, how does Bruce Banner transform into the raging embodiment of anger itself, the Hulk?

While both of these transformations are explained using ‘science’ by the comics that the fictional characters come from, Sebastian Alvarado – a biologist from Stanford University – has taken it upon himself to give a brief description of how modern day science could effectively explain these two heroes.

It may not be perfect and, as Alvarado points out, it can’t explain how the Hulk’s pants stay on after he transforms back to Bruce Banner, but it’s definitely worth a look for all of the comic book fans out there.

Captain America

The Hulk

[Source – Stanford University YouTube, Via – Polygon]