Final answer:
Prosimians, including bush babies, lemurs, and tarsiers, are nocturnal primates with smaller sizes and smaller brains compared to other primates. They possess large olfactory centers for smell, opposable thumbs for gripping, and a variety of teeth types for processing food.
Step-by-step explanation:
Prosimians are a group of primates that include various species such as the bush babies of Africa, the lemurs of Madagascar, and the lorises, pottos, and tarsiers of Southeast Asia. These primates are distinct from their anthropoid cousins, which include monkeys, apes, and humans.
Key characteristics of prosimians include being generally nocturnal and having a smaller size and smaller brains relative to anthropoids. They have unique adaptations such as larger olfactory centers in the brain indicating a strong sense of smell, which is useful for their nighttime activities. Moreover, prosimians often have longer snouts, which house their better-developed olfactory tissue.
Examples of prosimians include the ring-tailed lemur, known for its striking tail and social behavior, and the tarsier, with its large eyes adapted for night vision. With their varied habitat, including trees, swamps, and on land, prosimians have developed five fingers, including an opposable thumb, allowing them to hold objects and traverse through their environments efficiently. In addition to the opposable thumb, prosimians have a range of teeth types, allowing them to process various food sources.
Primates, in general, have trended towards larger brains and eyes, and smaller muzzles over evolutionary time. Early prosimian species experienced extensive diversification during and after the dinosaur era, but by the end of the Eocene epoch, many faced extinction due to changes in climate and competition with the emerging anthropoid species.