Find out which groups of animals have backbones. Life processes - Variation and classification - Vertebrates Learning Points Vertebrates are animals with an internal backbone. Vertebrates can be divided into five groups with distinctive features: mammals, birds, reptiles, amphibians and fish. A Twig Curriculum Film. Delivering key learning points. Get straight to the facts in just three minutes – directly linked to core learning, Twig's curriculum films will fit neatly into your lesson plans.