The new edition of Human Perspectives ATAR Units 3 & 4 has been extensively updated to address all aspects of the SCSA Human Biology ATAR course with the required depth and rigour. The content has also been updated to reflect current scientific methodology, research and knowledge. Unit 4 has been rewritten to ensure complete and concise coverage of all syllabus content. The series maintains all the features that teachers and students’ value, including syllabus links at the beginning of each chapter, a variety of question types and practical activities. The content is highly illustrated with annotated diagrams, photographs and electron micrograph images that are designed to engage students and to encourage scientific thinking, investigation and problem solving.