"The [single-celled] ancestor [of all animals] already had the tools that the cell needed to differentiate into different tissues," says Sabidó. "The cells that were around before animals were more or less prepared for this leap."[1]This was unpredicted by Darwinian evolutionists. If it were all simply accidental, it was highly fortuitous for the upward advancement of life on Earth.
"[This] means that the single-celled ancestor of all animals ... was more complex than scientists have previously given it credit for."[1]
References
[1] https://www.sciencedaily.com/releases/2016/10/161013155204.htm