Howler MonkeyHowler monkeys are the loudest of all monkeys. They call to let others know where their territory is, alerting them to stay away. The calls sound like a loud whooping bark or roar. After one group of howlers call, another group answers. Howler monkeys usually do this in the morning and at the end of the day. These monkeys live in Central and South America. At home in the forest, they hardly ever leave the treetops. They don't move very far each day, feeding leisurely at the very top of the forest canopy. Howlers mainly eat leaves, as well as fruits, nuts, and flowers. Howler monkeys get almost all the water they need from the food they eat. One of the few times they can be spotted on the ground, however, is during very dry spells when they need to find extra water. Howler monkeys have prehensile tails, or tails that can grip. The monkeys use their tails as a fifth limb to grip branches. Mostly it uses its tail to help grip branches as it eats and moves around high in the trees. Each family group is generally made up of 15 to 20 howlers. The leader is usually an old male. The head and body of adult howler monkeys range from 22 to 36 inches (55.8 to 91.4 centimeters) long and their tail can add 23 to 36 inches (58.4 to 91.4 centimeters). Though most species are classified as least concern, the Yucatán Black is endangered.
Spider MonkeySpider monkeys have long, thin arms with hooklike hands that allow them to swing through the trees. They do not have opposable thumbs. The brown-headed spider monkey has a prehensile tail, which means it can grasp and can be used like a fifth limb to grab trees. During the day, the spider monkey searches for fruit, which makes up the main part of its diet. They will also eat flowers, seeds, bark, leaves, and small insects during the dry season when fruit isn’t available. They spend most of the daylight hours climbing and swinging through the high canopy of trees. The brown-headed spider monkey lives in a large community of about 20 to 100 male and female monkeys. They split into smaller groups for feeding. Females usually give birth to only a single baby each year or two. Young monkeys are carried on their mothers' stomachs until about 16 weeks old. Then they are strong enough to ride on their mothers' backs. All brown-headed spider monkey infants are born with a pink face and ears. Spider monkeys hug each other and wrap their tails around each other. They are very intelligent and have robust memories. They were named spider monkeys because they look like spiders as they hang upside down from their tails with their arms and legs dangling. Their genus name is Ateles, which means “imperfect.” This refers to the fact that they don’t have thumbs. Hunting the brown-headed spider monkey is now prohibited in Ecuador, but humans have killed them for their meat for hundreds of years. Text by Anne A. McCormack / NGS Staff
Moment of PlayFebruary 21, 2023 – Party time! From tree-swinging orangutans to play-wrestling foxes, these seven critters know how to have a good time. Click through the photos to join the fun.
Monkey See, Monkey DoAugust 19, 2015 – Ayla the capuchin monkey lends a helping hand in Boston, Massachusetts.
Comeback critter: Golden lion tamarinMarch 17, 2023 – Scientists help these primates reclaim their forest home.
Check out the issue!November 14, 2025 – Score—it’s a snow day! Maybe you’ll go sledding, have a snowball fight, or snuggle up with some hot chocolate. When Japanese macaques get a snow day, these primates play, too. In this issue, you'll discover five fun ways these macaques—also known as snow monkeys—stay warm in their chilly habitat. First up? They go hot-tubbing!
New Monkey DiscoveredMarch 23, 2015 – Read about a newly discovered monkey in the Brazilian rain forest.
Wacky Weekend: PrimatesApril 29, 2016 – These awesome animals are letting it all hang out. Get the facts on primates when you take a look at these fun photos.
Moment of Oops!April 05, 2016 – Check out these silly photos of slipups, sticky situations, and tight spots.
Boa ConstrictorBoa constrictors are powerful snakes and stealthy hunters. They live in tropical climates throughout most of Central and South America, where they hunt at night. The boa's hunting technique is generally to ambush prey, such as rats, birds, monkeys, or wild pigs. The snake swallows its prey whole. Food is digested by strong stomach acids. After a large meal, a boa doesn't need to eat again for weeks. A boa constrictor grows throughout its whole life, which can be 20 to 30 years. An adult boa will generally weigh more than 100 pounds (45 kilograms) and grow to about 13 feet (4 meters) long. Boa constrictors tend to live alone. Mother boas give birth to about 60 babies at a time! A baby boa is on its own from the start. It is born with the instinct, or built-in knowledge, of how to hunt. It also has an instinct to hide to stay safe from predators. The baby boa's diet changes as it grows. The bigger it gets, the bigger its preferred prey becomes.
Ocelot: Can You Spot It?The ocelot quietly stalks through the grass in a Mexican forest. It crouches, then—bam!—pounces on an unsuspecting mouse. Dinner is served. The rodent probably never saw this wild cat coming. Its unique spotted coat helps it blend into the forest while it hunts for prey. The ocelot's camouflage also helps protect it as it sleeps during the day on tree branches or in bushes. Although the cat is twice the size of an average house cat, ocelots are prey for harpy eagles, pumas, jaguars, and anacondas. NIGHT CAT Ocelots are nocturnal, meaning they're most active at night. They use their sharp vision and hearing to hunt rabbits, rodents, iguanas, fish, frogs, monkeys, and birds. When they're ready to eat, the wild cats don’t chew their food—instead they use their teeth to tear meat into pieces and then swallow it whole. Like a domestic cat, an ocelot's raspy tongue can clean a bone of every last tasty morsel. CUTE KITTENS An ocelot family usually includes a mom and one or two young. The kittens are born with their spots but have gray coats and blue eyes that turn golden brown when they're about three months old. Ocelots live with their mom for about a year and then leave to find their own territory. There’s a whole lot to love about ocelots! Text by Allyson Shaw / NGS Staff
SlothIt's a good thing sloths don't have to go to school. They'd never make it on time. These drowsy tree-dwellers sleep up to 20 hours a day! And even when they are awake, they barely move at all. In fact, they're so incredibly sluggish, algae actually grows on their fur. Sloths live in the tropical forests of Central and South America. With their long arms and shaggy fur, they resemble monkeys, but they are actually related to armadillos and anteaters. They can be 2 to 2.5 feet (0.6 to 0.8 meters) long and, depending on species, weigh from 8 to 17 pounds (3.6 to 7.7 kilograms). There are two main species of sloth, identified by whether they have two or three claws on their front feet. The two species are quite similar in appearance, with roundish heads, sad-looking eyes, tiny ears, and stubby tails. Two-toed sloths are slightly bigger and tend to spend more time hanging upside-down than their three-toed cousins, who will often sit upright in the fork of a tree branch. Three-toed sloths have facial coloring that makes them look like they're always smiling. They also have two extra neck vertebrae that allow them to turn their heads almost all the way around! Some scientists think sloths developed their slow-motion lifestyle so they would be less noticeable to predators such as hawks and cats, which rely heavily on their eyesight when hunting. The algae that grows on sloths' fur also helps them avoid predators by letting them blend in with green leaves. They rarely come down from the trees. About once every week, they descend to go to the bathroom, slowly moving about by digging their front claws into the dirt and dragging their bodies. If they are caught by a predator, sloths turn from sluggish to slugger, biting fiercely, hissing, slashing with their claws, and shrieking.
Moment of Huh?March 25, 2016 – With computer programs, animals in photographs can appear to do just about anything—including ride a motorcycle! Check out tricky pics that'll make you do a double take.
Moment of Huh?March 25, 2016 – What is that? From pink lakes to superb birds, these photos will make you do a double take.
Design a house and find out which rainforest animal you are!July 08, 2021