Apex domains cannot have CNAME records.
Question and response
Question
dig zocalo.net. NS
Answer
zocalo.net. 4 NS ns.via.net.
zocalo.net. 4 NS ns2.via.net.
zocalo.net. 4 NS ns3.via.net.
zocalo.net. 4 NS ns4.zocalo.net.
Authority
The response has no authority records.
Additional
ns.via.net. 2 A 209.81.9.1
ns2.via.net. 2 A 216.218.130.58
ns3.via.net. 2 A 209.81.0.254
ns4.zocalo.net. 4 A 128.114.129.105
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0