A teen boy with a suspiciously English teacher vocabulary sets off with his Hot Babe Mentor and trusty telepathic dog on a quest that would be canon fodder for an episode of Penn & Teller's BullShit.
Besides Jack (our hero) speaking in whole pages of fragments, he also quotes romantic poets to himself and introduces million dollar words saying "Look that one up later, friends." Just a typical 18 year old jock, right? The dog and the Hot Babe Mentor aren't any more fleshed out as characters, either, which is why I recommend it to tween boys.
And then there is the plot. Jack is an eco warrior sent back in time to save the world from its unnatural use of science and technology. Got that? Cyborgs are bad technology (used only by the evil guys). Antigrav suits that let you fly are good technology (used by the good guys). Millions of years of humans genetically manipulating crops, domesticating animals, and creating technology to live better, healthier lives is unnatural. Women becoming shapeshifters and dogs becoming telepathic are natural (and I mentioned that both can with the aid of technology fly, right?).
This is where Penn & Teller would have a field day. The picture of pristine beauty of the stallion standing on the Outer Banks would not be possible without the direct interference of man. First of all, horses were domesticated to be built for humans, and secondly, they didn't exist in the Americas until the conquistadors brought them over. How is the development of the hero's telepathic dog any more natural than the development of the toy poodle? Does the author really think the toy poodle evolved that way to better cope with its environment?
As for technology, the author doesn't really point out what makes one good and another bad, other than who is using it. Why are cyborgs bad? What's so wrong with iron lungs, hip replacements, and the like? The antigrav suits the good guys use to fly around with weren't cooked up by hugging trees all day. What makes that technology good? Overall, a poor understanding of science and technology is shown, which dilutes the message of the book (well, and the ending where the deus ex machina saves the oceans without going into details).
If you want a nuanced look at characters and the impact of man on his environment in a young adult science fiction work, read the Uglies series by Scott Westerfeld. If you have a tween boy who needs to read lots of butt kickin', peacock struttin' adventure, pick up this one.