[colarris (OP)]

If life first started on Earth within the seas does that then mean that somewhere deep within us, perhaps in our DNA, there are still remnants of our watery past?

[Kryptid]

We share a good percentage of our DNA with fish, so yes.

[chris]

This is a really interesting question; thanks for asking it.

As @Kryptid points out, the observation that the genes present in humans (and many other animals) are close matches with those found in fish and, for that matter, right across the trees of life including plants and bacteria, is the strongest evidence we have for the existence of a universal common ancestor (UCA) for all life on Earth.

The fact that you can take a gene from any life-form, be it human, plant, or jellyfish, and insert it into the DNA of E.coli bacteria - where it will be interpreted correctly and the recipe that it encodes expressed as functioning protein - is proof that the code evolved once, and probably over 3.5 billion years ago.

On this basis, it's impossibly unlikely that the same genetic code, and genetic rules that govern the interpretation of that code, evolved identically, multiple times in parallel during evolution.

Therefore, we are related not just to the fish in the sea but also to the grass on your lawn, the algae on your front step and the bacteria living in your bowels. Quite a big extended family when you think about it!

[evan_au]

somewhere deep within us..., there are still remnants of our watery past?

Some current theories suggest that life began in hydrothermal vents, or in shallow ponds.

Inside each of our cells, there is a watery environment that may reflect that original environment.
See: https://en.wikipedia.org/wiki/Cytoplasm

[colarris (OP)]

Appreciate the replies and thanks for the answers. Interesting.

[chris]

Appreciate the replies and thanks for the answers. Interesting.

Thanks for the thought-provoking question!