1. Incisors and Canines: Placental mammals have specialized the frontmost teeth, called incisors, for cutting and biting food. Additionally, some placental mammals such as carnivores and primates possess canine teeth, which are often elongated and pointed, evolved to seize, hold and tear prey or food items.
2. Dental Formula and Cusps: Different groups placental mammals have varying numbers of teeth and specific patterns of cusps and other dental structures. These adaptations are closely associated with their diets, such as herbivores with broad teeth for grinding plants, carnivores with sharp cusps for cutting meat, or omnivores with a combination of features for both plant and animal matter consumption.
3. Ruminant Adaptations: Ruminants, such as cattle, sheep, goats, and deer, have a unique four-chambered stomach for efficient digestion of plant materials. This specialization includes the rumen, reticulum, omasum, and abomasum, allowing them to break down and extract nutrients from tough, fibrous plant tissues, and even regurgitate and re-chewing the food (process called "cud-chewing") to enhance nutrient absorption.