[autokad]

the wheel graphic could suggest (though not necessarily) that we evolved from a fresh water creature. Is there any theories on this that you guys know of?

it seems like it was always assumed to be a salt water creature, but it actually makes more sense in my head as a fresh water one, as it would pop into habitats conducive to terrestrial life

[tstactplsignore]

You're correct, the immediate ancestors of tetrapods almost certainly lived in freshwater, as known intermediate fossils like titaalik were found in fresh water stream deposits[1]. I believe all of the immediate ancestors of and early tetrapods have been found in fresh water deposits, although I can't confirm.

[1] http://tiktaalik.uchicago.edu/searching4Tik3.html