swinton

This is from the Wikipedia page on Life.

Evidence suggests that life on Earth has existed for about 3.7 billion years,^[52] with the oldest traces of life found in fossils dating back 3.4 billion years.^[53] All known life forms share fundamental molecular mechanisms, reflecting their common descent; based on these observations, hypotheses on the origin of life attempt to find a mechanism explaining the formation of a universal common ancestor, from simpleorganic molecules via pre-cellular life to protocells and metabolism. Models have been divided into “genes-first” and “metabolism-first” categories, but a recent trend is the emergence of hybrid models that combine both categories.^[54]

It means that life surged 3.7 billion years ago and that all life forms share fundamental molecular mechanisms. Meaning that all life comes from an universal common ancestor.

Well, does that mean that life surged then. The origin of life in the primordial soup happened ONCE, 3.7 billion years ago. 

My question is: did the conditions that allowed life to come to be disappear as soon as life was created? Why weren’t there other strains of life? Like now there are three main domains (Bacteria, Archea, and Eukarya) and they all share a common ancestor. Why did other domains not arise? Why didn’t they arise some time later (from other common ancestors) so that we have more diversity than just those three domains that are related?Or did it happen and we just haven’t classified it yet?