First life on dry land?

[paigetheoracle]

This may be old hat but could the mineral eating micro-organisms found inside a volcano a few years back, be the remnants of the first life forms on dry land? I know we have blue-green algae in fresh water and arthropods, like the Christmas Island crabs as well as amphibians but could these have predated all of them, considering the only thing to eat in what would have been a desert, would have been rocks?

[Eclogite]

I shall risk an accusation of semantic sophistry. The micro-organisms you refer to are in the land, rather than on the land, and therefore, do not qualify.

 

That said, I think your point is valid. We are finding micro-organisms in the most extreme and bizarre environments, including quite deep in the crust, or in the near surface layers of rocks in the Antarctic.

 

However, I think the colonisation of the land is generally thought to refer to macroscopic organisms, in which case the examples you mentioned would be the principal contenders.