Fossil evidence of this trip from single-celled to multicellular is scarce. Those first organisms were soft; a billion years or so later they do not leave any marks. However, scientists, working in their labs, have done a pretty good job of recreating this last transition. The evidence indicates the trip from single-celled to multicellular was a step-by-step process, a convergence, and not one big dramatic change.
In the absence of fossils, estimates of when this last step happened conflict. Based on evidence available suggest multicellular appeared about 1.5 billion years ago, or 2.2 billion years after first life began. However, the appearance of two genders will indeed speed things up.
Now, a quick review of those “six colossal and scientifically explained events.”
What does science say about those six steps?
Start with the Big Bang.
An inquisitive mind is saying, “What caused the Big Bang?” Science has no response to the cause. Well, “What was there before the Big Bang?” Some say “nothing.” Others believe the Big Bang is part of an endless cycle, that mass and matter existed previously, slowly crushed down to one point. Then Big Bang 2, and the cycle goes around again – and again – and again — throughout infinity.
But wait: the cycle cannot exist unless it started at some time. So the question remains, “What caused Big Bang?”
What has science to say about gravitational attraction?
Every piece of mass in the universe is attracted to every other piece of mass in the universe. Gravity appeared immediately with Big Bang. What caused that?
Einstein said space and time curved sort of like the capital letter “U.” One side was heavier so the lighter objects on the other side fell toward it. To scientists, that makes sense in the big, big picture but does not explain why the dropped pencil was pulled toward the desk.
Much research effort has been directed toward a little particle called graviton, theorized to be the cause gravitation force. The search to find one has not been successful. It seems the world of gravity and the world of subatomic particles (electron, neutron, and so forth) will live side and never fit into one unified theory.
Newton gave us the equation but not the cause. In his book, Lloyd describes this a “a mysterious thing” and “force of gravity, a kind of invisible glue that makes everything in the universe want to stick together.”
So what caused life to begin?
In the 1950s, two scientists did produce amino acids, the building block for life, from gases which were available at life’s beginning. This caused a good deal of excitement, but no one has been able to make those amino acids produce a cell machine that reproduced itself. Compared to living animals today, the prokaryotes DNA is simple; but compared to no DNA at all, the prokaryotes are very, very complex. Somehow, organic grew from inorganic. That step was not in any way simple!
Trust me, scientists have tried and tried to repeat the process in the lab. But by 2001, a leading science journal reported, “Scientists are far from creating life in the laboratory, and it may never be possible to prove exactly what chemical transformations gave rise to life.” No matter how hard chemists, biologists, and molecular biologists tried, they could not replicate those last steps to life.
Some scientists speculated that life was carried to earth on a comet. Proof of that claim is unlikely. In 2009, Scientific American reported, “Scientists are now aiming at creating fully self-replicating artificial organisms.” Notice this article did not use the word “life.” The target has gone from “life” to “an artificial organism.” A year later, another scientist wrote, “It is virtually impossible to imagine how a cell’s machines could have formed spontaneously as life arose about 3.8 billion years ago.”
One of religion’s sharpest critics (Dawkins) agreed, writing, “The origin of life only had to happen once. We can therefore allow it to have been an extremely improbable event, many orders of magnitude more improbable than most people realize.” In other words, to a person with a Ph.D. in statistics, he is saying, “This event was not caused by randomness.” Hmm.