Physical Appearance:
* Spider monkeys: Have very long, slender limbs, prehensile tails (used like a fifth limb), and small heads. They are incredibly agile and known for swinging through the trees.
* Howler monkeys: Have shorter, stockier limbs, a prehensile tail, and a large, round head with a distinctive, bony structure on top. Their most defining feature is their large vocal sac that they use to make their incredibly loud roars.
Diet:
* Spider monkeys: Primarily frugivores, meaning they mainly eat fruits. They also eat leaves, flowers, and occasionally insects.
* Howler monkeys: Are also mostly frugivores, but they eat a higher proportion of leaves than spider monkeys. They have a more complex digestive system that allows them to digest tough plant matter.
Social Structure:
* Spider monkeys: Live in smaller, less cohesive groups than howler monkeys. They have a flexible social structure and often break off into smaller subgroups.
* Howler monkeys: Form large, territorial groups that can include up to 15 individuals. They have a strict social hierarchy, with a dominant male leading the group.
Vocalization:
* Spider monkeys: Have a wide range of vocalizations, including whistles, barks, and screams. They communicate using these sounds for a variety of purposes, such as warning of predators, finding other members of their group, and maintaining social bonds.
* Howler monkeys: Are famous for their incredibly loud, booming roars that can be heard for miles. They use these calls to communicate with other groups, defend their territory, and attract mates.
Other Differences:
* Habitat: Both species are found in Central and South America, but spider monkeys prefer tropical rainforests while howler monkeys can also be found in drier forests.
* Locomotion: Spider monkeys are known for their acrobatic swinging and brachiation (swinging from branch to branch using their arms). Howler monkeys are less agile and prefer to walk and leap.
In Summary:
While both spider monkeys and howler monkeys are fascinating primates, they differ in their appearance, diet, social structure, vocalization, and other behaviors. These differences are adaptations that allow each species to thrive in their respective environments.