At the north end of Santa Monica Beach, there’s a fenced off 2-acre section that looks a bit unkempt. It’s an experiment in “re-wilding,” or restoring the beach to what it looked like before humans altered it. The pilot project, a partnership of The Bay Foundation and Santa Monica, could also help protect the city from sea level rise. The Bay Foundation first staked out the plot in December 2016, but waited until Tuesday to hold the official ribbon cutting, so visitors could see dune plant seedlings emerging from the sand.