Tree Growing Around a Deer Skull... interesting find by the EBL Crew

The EBL team spends much of its time out in the field collecting data and once in a while we come across strange and unique findings. EBL'ers Martin Kastner and Zia Crytser came across one of these findings just the other day. It is a deer skull stuck in a tree and the tree has grown around it. Any ideas about how this happened? (Photo taken by Zia)