Species identification has gained importance due to its role in wildlife forensics, particularly in illicit trade, criminal use of wild animals, monitoring environmental changes, and the study of disease epidemiology in the animal kingdom and the biodiversity conservation concerns. Based on conventional morphological characteristics, geographical distribution, or behavioral traits, the science is facing multiple challenges due to climate change, which in turn induced morphological and behavioral evolutions. The taxonomic identification via blood typing is a complementary approach to the conventional ones rooted in immunological principles, leveraging antigen–antibody interactions to discriminate between biological taxa. Special emphasis is placed on the forensic and wildlife applications of blood typing, including its integration with DNA-based species identification in wildlife crime investigations and biodiversity monitoring. This chapter is focused on the major concepts of blood typing, deciphering evolutionary aspects in major taxa as primates, canines and felines, and mice, and will give a brief overview of recent advancements in the field.