Speaker for the Dead by Orson Scott Card
Speaker is the sequel to the book Ender's Game, which features a young kid owning other kids, adults and even an aggressive alien race. Space, intergalactic war, mind-games and strategy abound throughout Ender's Game. If you haven't guessed, these books are science fiction!
Speaker takes place quite a few years after the events of the first book. It takes a more anthropology-oriented angle of storytelling, as a remote planet's colony has to study a new race of aliens without contaminating the aliens with human culture. All sorts of problems arise, and stuff goes down. And it's up to Ender and his wizardy mind to sort everything out. Culture vs. government vs. science vs. emotion!
I can't really explain much more without giving away either of the books, but I'll just say that they are great. And I love them. Oh, sci-fi.
Well I guess I can explain the title: A "Speaker for the Dead" is a person whose vocation is to learn everything he or she can about a deceased person or group of persons and tell a completely true account of the subject. This could involve revealing once-private secrets to making the audience realize things about their own lives, in relation to the deceased person or group. Ender Wiggin, the main character from the first book, is now a Speaker. And a darned good one!
The illustration is of a Pequeninos (one of the aliens that the colony on Lusitania is trying to study). They are nicknamed "piggies" because they remind the humans of, well, pigs. Throughout the course of the book, much of the piggy culture and their connection to the ecosystem is revealed. It's really interesting!
I should also explain why he's holding a tree branch. The piggie culture is very, very closely tied to the forests in which they live. The trees are held sacred and the piggies communicate with them by means of a percussive language. Lucky for the colonists, no human has ever cut down a tree in fears that they would give the piggies any ideas about saws or technology. That would have been the end of the colony! The piggies love battle.