We all know we need iron to live. How else would our blood carry oxygen to our lungs? And cells need iron in order to multiply. The problem is that our cells aren’t the only ones who need iron in order to thrive. Cancer cells and microorganisms like E. Coli and staph need iron too.
This means that the ice cover contains microorganisms that date back thousands of years; recently scientists found microorganisms that froze way back when Rome was founded.
The third kingdom contains all organisms whose cells have a nucleus, including plants, animals, algae, and even fungi. So evolutionarily speaking, humans and fungi are cousins.