"Dinosaurs" novelist Lydia Millet has long worn her green heart on her authorial sleeve.

Concern for our planet, its environment, its creatures and its imperiled future distinguishes her best fiction. Concurrent with her lauded writing, Millet has worked at the Center for Biological Diversity, where she is deputy creative director, helping save plant and animal species from extinction.

"We Loved It All," Millet's first book of nonfiction, marries passion and profession in a hybrid of memoir, op-ed and scientific abstracts that is bracingly earnest and intermittently engaging, but fails to deliver a cohesive call to action.

The book comprises a series of disparate subjects briefly broached — for a paragraph or three, rarely more than a page — then discarded. Stylistically, it evokes Millet's friend Jenny Offill, but where Offill's spare novels remain beholden to a story, Millet's project feels unbounded, making it more akin to a scroll through social media.

Topics leap from the nuances of prairie dog language to the logistics of Millet's "falling-asleep imagery," to the benefits of an abundant sclera in the human eye, from corvids' (such as ravens and crows) ability to play tricks on dogs and cats, to Millet lying awake at night, contemplating loneliness and death.

She shares her love of her kids and concerns for their future. She sketches her background, including an all-too-brief evocation of a year studying in the south of France, which reminds readers of her scene-setting prowess. And she drops grudges she's clung to, like the fact that a typo she missed when copy-editing a porn magazine resulted in an apology being issued to the article's author, an "unrepentant" serial killer.

She highlights familiar sources of despair for her circle of "progressive, educated, and usually middle- or high-income" folks: the de-emphasis on education, death of common sense, denial of facts, the consequences of the Citizens United decision. And she drops a lot of science, of varying robustness, including findings about the intelligence of octopuses and orangutans, as well as the memories and parenting strategies of "organisms of the green world."

Impassioned passages about endangered species are moving, but other ideas can feel esoteric. She considers the advantages of granting legal "place-personhood" status to geographic features and questions the lack of agency of nonspeaking pets in fiction, an inquiry somewhat undercut by earlier discourse on Halloween costumes for real-world pets. Her family chose the "bumblebee rig, size small" for their pug, presumably with its consent.

Some readers might have a hard time caring about, say, the rights of "the green," when nonbinary humans are getting beaten in school bathrooms and frozen embryos are being deemed children in court. Activist concern should not have to be pragmatic, but reserves of mental capacity, money and outrage are not unlimited.

Millet confesses that, increasingly, her writing "takes the form of prayer," but it's unclear what exactly she's praying for here, which was never the case in novels like "The Children's Bible." Perhaps the difference is best explained early in "We Loved It All," when Millet writes: "Information that gets conveyed to us outside the linear excitement of narrative ... is taken up by our minds with disinterest. Or not at all. Only story can bring it home."

Cory Oldweiler is a freelance writer.

We Loved It All

By: Lydia Millet.

Publisher: Norton, 272 pages, $27.99.