Genomes are huge. My 3-year-old daughter and I had a discussion about this. We came to the conclusion that it would take approximately 165 years to "stamp out" the human genome with her new stamping pad set. She was impressed!
Evolution and development of dorsal-ventral axis specification in Eucidaris http://dx.doi.org/10.1101/044149
http://dx.doi.org/10.1101/044149 Posted to PDF for comments and citations at http://biorxiv.org/content/early/2016/03/16/044149 Submitted to PLOS Genetics