The foods consumed by these animals – such as seeds, insects, plants, and fruits – are manipulated with their fingers. This applies especially to seeds, which are a fundamental resource for rodent diversification.
Due to their difficult access, these foods are rarely consumed by other mammals but are common in rodent diets thanks to the development of incisors and masticatory muscles. According to the research, the presence of thumb nails is also an important factor that enables access to these resources.
The pattern of food consumption is divided into oromanua, when the animal brings food to its mouth using its paw, and oral, when food is consumed without using the paws.
The study identified that groups that completely lost the unguis or the thumb are associated with oral feeding. This way of consumption varies among species that feed on grass and pasture, such as capybaras, and species of squirrels from the Philippines that feed on tree bark using only their teeth.
Rafaela highlights that most species with claws are animals adapted for digging and living underground, known as fossorial species.
