You deleted my previous response to this because I used the words "my dear", or because the message itself was ****ing to you?
You believe in evolution, Julie, you just described it. You just need to remove the line in the sand you make up regarding no "continued unlimited" variation.
There is no such limit.
Can you show us examples of how variation is NOT unlimited (outside of the organism *surviving*, of course)? What are the mechanisms that prohibit it from being unlimited? It's up to you to prove (or even SHOW) there's even one mechanism there, otherwise the variation just keeps on going and going - as evolution predicts and shows!
You're SOOOO close, Julie! Just one more step and you'll be an evolutionist! Welcome to the real world!
And oh, by the way - read the CONCLUSION of the paper you quoted:
"A Biological Big Bang (BBB) model is proposed for the major transitions in life's evolution. According to this model, each transition is a BBB such that new classes of biological entities emerge at the end of a rapid phase of evolution (inflation) that is characterized by extensive exchange of genetic information which takes distinct forms for different BBBs. The major types of new forms emerge independently, via a sampling process, from the pool of recombining entities of the preceding generation. This process is envisaged as being qualitatively different from tree-pattern cladogenesis."
“The Biological Big Bang model for the major transitions in evolution,” Eugene V Koonin, National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, in Biology Direct 2007, 2:21.