David B. Givens has recently retired as a teacher in the School of Professional Studies at Gonzaga University, USA, and is the Director of the Center for Nonverbal Studies. He began studying "body language" for his Ph.D. in Anthropology at the University of Washington in Seattle, USA. He served as Anthropologist in Residence at the American Anthropological Association in Washington, DC from 1985 to 1997 and has previously taught Anthropology at the University of Washington. His expertise is in Nonverbal Communication, Anthropology, and the Brain. He has published numerous books and articles on the topic of nonverbal communication, including Love Signals: A Practical Field Guide to the Body Language of Courtship (2005); Crime Signals: How to Spot a Criminal before You become a Victim (2008); The Routledge Dictionary of Nonverbal Communication (Routledge, 2021); and A Guide to Sight-Reading the Body Language of Business, Bosses, and Boardrooms (2024).

John White works as an Assistant Professor on undergraduate and postgraduate education programs at the Institute of Education, Dublin City University (DCU). He currently works as Director of the DCU Changemaker Schools Network. His research interests include language acquisition, nonverbal communication, primary education, embodied cognition, arts-based research, mathematics education, science education, and changemaker practices. He is the co-author of two books on nonverbal communication: The Classroom X-Factor: The Power of Body Language and Nonverbal Communication in Teaching (Routledge, 2011) and The Routledge Dictionary of Nonverbal Communication (Routledge, 2021).

Acknowledgments Prologue: Nonverbal Steps to the Origin of Language Chapter 1: Step 1 (3.7 Billion Years Ago): Chemical Messages-"I Am Here" Chapter 2: Step 2 (500 Million Years Ago): Vertebrate Messages-"I Am Here" (Advent of "I"/"Me") Chapter 3: Step 3 (500 Million Years Ago): Vertebrate Messages-"You Are There" (Advent of "You") Chapter 4: Step 4 (150 Million Years Ago): Mammalian Emotion Chapter 5: Step 5 (150 Million Years Ago): Mammalian Acrobatic Tongue Chapter 6: Step 6 (65 Million Years Ago): Primate Binocular Vision Chapter 7: Step 7 (65 Million Years Ago): Primate Grasping Hands Chapter 8: Step 8 (65 Million Years Ago): Primate Dexterous Lips Chapter 9: Step 9 (35-40 Million Years Ago): Higher Primate Facial Communication Chapter 10: Step 10 (24 Million Years Ago): Primate Food Sharing Chapter 11: Step 11 (2.6 Million Years Ago): Human Tool Making Chapter 12: Step 12 (1.9 Million Years Ago): Object Fancy Chapter 13: Step 13 (1.9 Million Years Ago): Pointing-"It Is There" (Advent of "That") Chapter 14: Step 14 (1.9 Million Years Ago): Human Cranial Capacity Increase Chapter 15: Step 15 (200 Thousand Years Ago): Sonorous Human Larynx Chapter 16: Conclusion: Language Migration, Visual to Vocal Epilogue Index