It's hard to really tell from the small versions here — which is a lesson in itself, because at 1280x850, which is a perfectly fine online viewing size, the differences really _don't_ matter that much.

However, in this case, I think Auto probably _did_ make some better choices.

Shutter Speed
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You picked ¹⁄₆₀th of a second. This is fine, but probably slightly susceptible to blur from camera motion shake or subject movement due to wind.  Auto mode picked ¹⁄₄₀₀th, which will better freeze things.

ISO
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You picked 200 and the camera picked 400. Like most modern largish-sensor cameras, there's not much difference between 200, 400, or 800 on this camera in terms of noise, but I suspect the auto mode enabled the expanded dynamic range option (where the camera actually shoots at a lower ISO and then brings up the shadows in internal post-processing). Because of the way that works, this is only available at higher ISOs than the base 200. (The difference isn't super-visible in the result, but I can imagine a _little_ more detail in the shadows.)

Aperture
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This is really the big one. You picked f/18, and the camera picked f/8. All camera-lens systems are subject to diffraction, which means that while the narrower aperture gives you more depth of field, there's less sharpness overall. See https://photo.stackexchange.com/questions/8304/what-is-a-diffraction-limit for more. In general, it's better to not go beyond f/8 except in special circumstances.

Overall Exposure Value
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It's helpful to think of exposure differences in terms of "stops" — that is, poewrs of two. (See https://photo.stackexchange.com/questions/15706/what-is-one-stop). Between f/8 and f/18, there are 2⅓ stops — going in that direction, darker, so we'll call it negative 2⅓. And between ¹⁄₄₀₀th and ¹⁄₆₀th is just about the same: 2⅔ doublings (which is 2⅔) — but in the direction of more exposure. So these things should just about cancel out. (See https://photo.stackexchange.com/questions/72388/what-is-the-relationship-between-iso-aperture-and-shutter-speed for more on this).

One would expect, therefore, a ⅓-stop change in aperture to get to exactly the same place. But 200 to 400 is a full stop, so that's a ⅔-stop discrepancy, which is kind of a mystery (that would normally result in a visibly brighter exposure), but I _think_ that this is because of the dynamic range expansion effect I mentioned. (A change in the light would be another explanation, but that seems unlikely with no clouds in the sky, the same general framing, and less than a minute apart.)