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Your Mac will actually come with iPhoto, which can handle raw files. I think it's more aimed at non-serious photographers, but can't really say as I've never used it. It came with my Mac but I never installed it.
Adobe Lightroom is the industry standard, and Aperture is an alternative.
The thing to understand about the Mac software world is that old OS versions get desupported at around 2-4 years of age, but it tends to be cheap or free to update the OS. This is different from the Windows world, where you buy the machine, often can't get driver support for new OS versions, but MS push out security updates for a decade. Apple don't. You upgrade the OS or you get left behind and the machine is not safe for online use. Apple also deprecates and removes APIs, which means old programs break!
Unfortunately the Japanese photo manufacturers, including Nikon, Epson and Canon, don't always update their Mac software in a timely way, or sometimes at all. The software for my Nikon scanner hasn't run on current OS X versions for years. It means you'd need a second computer to do Internet banking etc.
Adobe software does not pick up camera settings even when they're in the raw file, for Canon not even the white balance.
Raw conversion algorithms are well known and common to almost all digital cameras (Fuji and Samsung being exceptions) so Nikon does not have any advantage in coding their software. But Adobe can do it once for all cameras, so better.
If you do use Adobe software, use the "Camera" profiles, not "Adobe Standard", so your colours match the JPEGs.