Uh, no. MacOS and OS X is actually UNIX™ not Linux. Linux is a clean-room work alike constructed copy of UNIX™.
Apple macOS and OS X are the world's best selling, completely certified POSIX® compliant and TradeMarked by the Open Group versions of UNIX™ being sold today. UNIX preceded Linux by at least two decades.
For a good explanation of the history of the two, read this link.
Ya. Just noting that Ubuntu looks a lot like my dads old Mac.