Monotremes 1 Duck-billed platypus Spiny anteater.
Characteristics of Mammals. Key Characteristics of Mammals All mammals have the following in common: – Are endothermic – Hair – Specialized teeth – Females.
Groups of Mammals. Classification of Mammals Mammals range in size from a tiny shrew (1.5 grams) to a blue whale (150 tons) Mammals inhabit more environment.
