Swedish climate campaigner Greta Thunberg waits in Erkelenz, Germany, to take part in a demonstration at a nearby a coal mine on Jan. 14. Michael Probst/AP hide caption

On Animals, by Susan Orlean Avid Reader Press hide caption

Graceland, At Last: Notes on Hope and Heartache From the American South, by Margaret Renkl Milkweed Editions hide caption

Fox & I: An Uncommon Friendship, by Catherine Raven Spiegel & Grau hide caption

Evolution Gone Wrong: The Curious Reasons Why Our Bodies Work (Or Don't), by Alex Bezzerides Hanover Square Press hide caption

Mom Genes: Inside the New Science of Our Ancient Maternal Instinct, by Abigail Tucker Gallery Books hide caption

Hooked: Food, Free Will, and How the Food Giants Exploit Our Addictions, by Michael Moss Random House hide caption

Exercised: Why Something We Never Evolved to Do Is Healthy and Rewarding, by Daniel E. Lieberman Pantheon hide caption

Fevers, Feuds, and Diamonds: Ebola and the Ravages of History, by Paul Farmer Farrar, Straus and Giroux hide caption

Kindred: Neanderthal Life, Love, Death and Art, Rebecca Wragg Sykes Bloomsbury Sigma hide caption

A page on Swallows from David Allen Sibley's What It's Like To Be A Bird. David Allen Sibley/Knopf hide caption

Becoming Wild: How Animal Cultures Raise Families, Create Beauty, and Achieve Peace, Carl Safina Henry Holt and Co. hide caption

Wildhood: The Epic Journey from Adolescence to Adulthood in Humans and Other Animals, by Barbara Natterson-Horowitz and Kathryn Bowers Scribner hide caption

Franz Boas. ullstein bild Dtl./ullstein bild via Getty Images hide caption

Late Migrations: A Natural History of Love and Loss, by Margaret Renkl Milkweed hide caption

From Giants of the Monsoon Forest: Living and Working with Elephants by Jacob Shell W.W.Norton & Co. hide caption

Underland: A Deep Time Journey, by Robert Macfarlane W.W.Norton & Co. hide caption

Mama celebrates her 50th birthday on May 3, 2007, with fruit and vegetables at the Burgers Zoo in Arnhem, Holland. AFP/Getty Images hide caption

Band-e Haibat lake at Band-e Amir National Park. MCT via Getty Images hide caption

In Search of the Canary Tree, by Lauren E. Oakes PR hide caption