Take a look at SARS-CoV-2's family tree. It's full of surprises

In many ways, viruses are like families — giant, complicated, extended families with cousins, aunts, uncles, grannies and grandpas galore.

Just as with human families, scientists can generate family trees for viruses, showing how each member (or variant) is related to the others. Children are connected to parents by branches, and cousins are connected through their grandparents.

For viruses, these family trees give biologists insights into how a virus has evolved over time and what changes to expect in the future.

During the pandemic, the family tree of SARS-CoV-2, the coronavirus that causes the disease COVID-19, has produced more surprises than anyone expected.

It turns out the SARS-CoV-2 family had two black sheep that it kept hidden from the world. When those relatives appeared, seemingly out of the blue this autumn, they not only shocked the world, but they also made evolutionary biologists question