¿Caimán o cocodrilo? (Alligator or Crocodile?)

What’s the difference between a seal and a sea lion? These “second cousins” of the sea look similar, but there are many ways to tell these creatures apart. From ear shape to the noises they make to communicate, seals and sea lions are amazing creatures with both shared features and many truly unique attributes. They both share an ocean habitat, but when readers take a closer look, it’s easy to discover how they each fight off predators, mate, and raise their young in different ways. Captivating full-color photographs help to bring these marvelous mammals to vivid life.

Se trata de una pregunta que nos inquieta solo de pensarla, tan profundamente dependen nuestras vidas y sociedades del mundo científico-tecnológico de la electricidad. Entre los grandes protagonistas de ese mundo, destaca un serbio que después de estudiar ingeniería en Graz (Austria), emigró en 1884 a América, instalándose en Nueva York; un serbio de imaginación y habilidades descomunales, un excéntrico sin miedo a lo desconocido, que gozaba montando espectáculos para promover sus inventos: Nikola Tesla (1856-1943). Es difícil apreciar cuánto debemos a sus inventos: sus ideas y...

“Dino” Don Lessem brings readers face-to-face with various dinosaur species, detailing their habitats, way of life and how they became extinct. An acclaimed dinosaur expert, Don Lessem has written more than 30 children’s books, writes a popular dinosaur column in Highlights magazine, and was an adviser for Jurassic Park. Take a trip through dinosaur time to meet these small dinosaurs face-to-face: Little Lesothosaurus was the length of a house cat! Epidendrosaurus could climb into trees like a squirrel! Liaoceratops had body armor and horns-and was only the size of a collie dog! Plus,...

"Viaja a las profundidades del océano en busca de las criaturas más grandes y fantásticas del planeta. En este libro bellamente ilustrado, encontrarás animales que han inspirado las leyendas de las serpients marinas y las sirenas. Mientras viajas por los mares, puedes ensamblar cinco criaturas marinas diferentes con las piezas intercambiables, o crear tus proprios monstruos sobrenaturales"--Container.

"Some things are so huge or so old that it's hard to wrap your mind around them. But what if we took these big, hard-to-imagine objects and events and compared them to things we can see, feel and touch? Instantly, we'd see our world in a whole new way." So begins this endlessly intriguing guide to better understanding all those really big ideas and numbers children come across on a regular basis. Author David J. Smith has found clever devices to scale down everything from time lines (the history of Earth compressed into one year), to quantities (all the wealth in the world divided into one...