10 Reasons Why Humans May Not Have Come From Earth

Ahh, it's that classic summer scene. The moment there's a little bit of sun, every spare bit of grass, beach or garden is littered with people turning gradually pinker.

But why is that? Why does our own sun do us so much harm?

This is one of Ellis Silver's arguments for our alien origins. Humans will easily burn through sun exposure, whereas many creatures won't.

Humans, in contrast with other species, cannot sunbathe for more than short periods at a time without getting sunburned. This indicates that the human body is not effectively adapted to constant exposure to our sun, which is a funny thing for a species that have no protective layer of fur.  

Our own sun, from which all life on Earth draws its energy in one way or another, will literally give us cancer if we stay out in it too long, other creatures have evolved so that this doesn't happen. A lizard, for example, can sit out all day and not get so much as a tan line and some corals even produce their own SPF to protect themselves. 

Silver thinks that this is because we evolved with a much weaker sun, or perhaps we originated on a planet with lots of cloud cover.

Another thing that he highlights as odd is the fact that humans seem to suffer from seasonal mental disorders such as Seasonal Affective Disorder. Other animals migrate, hibernate or just tough it out when it comes to surviving an Earth winter, but humans just can't seem to hack it.

We can't cope with a lot of sun, we can't cope with a lack of sun - why are we so ill-suited to the comings and goings of the seasons if we've spent millions of years evolving on this planet?