Gr 7 Up Scientific expeditions to unexplored South American jungles inhabited by the Jivaro Indians (or Shuar, as they call themselves) don't take place every day. Here is a slender record of just such a venture, made by ten young scientists and a group of Indian and Ecuadorian porters and muleteers into the rain forests of the Cutucu Mountains to study birds. The book records a venture that ran progressively downhill. The Indian and Ecuadorian porters hated and mistrusted each other, and finally the Ecuadorians decamped, taking the mules and tons of valuable supplies. The scientists struggled on, eating the likes of rock-sucker lips and moldy rice. Finally, desperate for food and threatened by the Shuar, whose trophies were shrunken heads decorated with feathers and monkey fur, the expedition breaks into two groups and retreats safely to the known world. An exciting venture, but readers will want to know more about it than this all too brief account provides: more about the personalities of the participants, about the research that was done, about the birds they found, and about the Shuar. The black-and-white photos are sometimes muddy and lack resolution. They cry out for color. Still, it's a beginning; a tantalizing tidbit to whet one's appetite for adventure; a glimpse into a strange world; and a startling example showing that even on a scientific expedition, things can go wrong. Patricia Manning, Eastchester Public Library, N.Y.