Which type of vegetation has little dietary value for most primates due to its digestibility?

Mature leaves are considered to have little dietary value for most primates primarily due to their low digestibility. Many primates prefer younger leaves or developing plant parts because these are generally easier to digest and have higher nutritional content. Mature leaves often contain higher levels of cellulose and tannins, which can be tough to break down and may contain compounds that can hinder digestion or nutrient absorption. This is particularly important for animals like primates, who need to optimize their energy intake from food sources.

In contrast, fruits are usually quite palatable and rich in sugars, making them easily digestible and an attractive food source. Nuts, while nutrient-dense, can be difficult to access and may require specialized adaptations for cracking. Flowers can provide some nutrients as well, but they are not a primary dietary component for most primates. Thus, mature leaves stand out as the vegetation type that poses significant challenges in terms of digestibility and nutritional value for these animals.