All forms of multicellular life here on Earth begin with just a single cell.

From this one cell springs a stream of specialized cells that go on to serve needed functions to create and keep a new life-form alive.

This complex process is one of nature’s greatest mysteries.

A zebrafish egg cell forms a complex embryo in only a few hours. (Fengzhu Xiong and Sean Megason)

But now, scientists from the Harvard Medical School and Harvard University say they have tracked the progression of how one cell builds into a more complex lifeform.

The researchers used single-cell sequencing technology to meticulously outline individual cells in developing zebrafish and frog embryos over the first day of life.

This allowed them to build a detailed roadmap of how multicellular life can be built from one solitary cell.

The researchers’ findings were described in three studies that were published in the journal, Science.

Study #1 Link    Study #2 Link    Study #3 Link