One of the sad (or maybe good) things about the modern era is that there are so many people who are so good at so many things. It used to be that photorealistic paintings or sculptures were limited to a few master artists who had studied for entire lifetimes. Now, works of art are a dime a dozen, some excellently rendered, some...well...not so much. I can appreciate many types of art for their 'artistic' merit (whatever that means), but sometimes I take the simple statement of "I don't know art, but I know what I like" to heart.
That said, I like wildlife art. I wouldn't really classify any of it as 'great art' (though I'm certainly willing to be convinced by someone more knowledgeable than I), but I like some artists. Two of my favorites in the realm of photorealism are Terry Isaac and Robert Bateman. Terry Isaac wrote a book that I bought back in junior high called Painting the Drama of Wildlife Step by Step. The book is very well done: full of vivid pictures of his own art, detailed enough in its advice to be helpful, but not so detailed to be oppressive. I've only looked at Bateman's works in books.
Below are two examples of their work, the first, Catwalk, by Terry Isaac and the second, By The River by Robert Bateman.