The Biology and Behavior of the Living Primates

A Comparison of the Lesser Apes and Monkeys

All gibbons and siamangs are arboreal and brachiators (hand over hand swinging from branch to branch).All gibbons and siamangs are small in body size and have extremely long arms and legs relative to their body size. Newworld monkeys have tails but are more balanced without them. Old world monkeys have tails but use them less for balance.Apes do not have tails.

What are the differences between apes and humans?

Apes and humans have several differences. Apes have a no tail, are generally larger in size, and have a larger brain size relative to their body size. Apes also have more complex brains and greater intelligence and learning ability. They also invest more in their young. Humans, on the other hand, have a different dental formula (2-1-2-3) and a lower molar structure with 5 cusps (raised areas on the chewing surface of the tooth) instead of 4 (as monkeys have). This is called the Y-5 pattern. Additionally, humans have a more developed language and communication system and are capable of abstract thought and reasoning.

The Social Lives of Baboons: Dominance Hierarchies and Coalitions (example of OWM)

Baboons are a genus of primates that live in groups of 20-200 multimale/multifemale groups on the African savanna .Open grassland with food spread out over large areas provides protection from predators. The baboons' diet is diverse, including grass, leaves, fruit, and some meat from hunting small animals and birds. The social organization of the baboons is that adult males are dominant over adult females, and there is a constant shifting of the relative position of the most dominant males. Aggressive actions are important in the dominance hierarchy of the baboons. Environmental factors are involved in the dominance patterns of the baboons, such as the presence of forests. The continuity of the baboons' society revolves around females. The males often move from one group to another.

Exploring the Fascinating World of Bonobos

Bonobos is the preferred term for the pygmy chimpanzee, which is the same genus as the common chimpanzee. They are genetically and physically very similar to the common chimpanzee Bonobos have longer legs, higher centers of gravity, and narrower chests than common chimpanzees. They are more easily upright than other apes, and some sexual dimorphism exists, with adult males averaging 95 pounds and adult females 73 pounds. Females are the most dominant in the social structure of bonobos, and the hierarchy depends on the females which are different from the chimpanzees. The dominance of males depends on the dominance of their mother

Exploring the Fascinating World of Chimpanzees

Chimpanzees are found in Africa Adult males weigh 99 pounds and females weigh 82 pounds Chimpanzees are more active and agile than gorillas Chimpanzees spend a lot of time in the trees Chimpanzees have a social structure that constantly changes Individuals leave and join the group, and smaller subgroups form with the group The mother-child bond is central to the chimpanzees social structure, with bonds lasting a lifetime Chimpanzees spend springs spending a lot of time with their mother learning mothering techniques Adult males are generally dominant over adult females, but some females are dominant over lower ranking males The difference in dominance can be seen when comparing chimpanzees to humans

What are the differences between gibbons and other primates?

Gibbons differ from other primates in several ways. They use their arms for balance while swinging from branch to branch, have long fingers and short thumbs, and use their hands like hooks to swing. They also have no sexual dimorphism, with both sexes having large canines but males being slightly larger. Gibbons are also monogamous and mate for life, unlike other primates. Additionally, they have a monogamous family structure, with no dominance, and defend their territories with loud vocalizations and aggressive displays. Finally, gibbons live in tropical rainforests in Southwest Asia, which have constant heavy rainfall and rich and diverse vegetation.

Classifying Hominoids: Morphology, Genetics, and Species

Hominoids are primates that evolved from earlier species about 20-8 mya ago. There were many types of hominoids during this time, but today only a few survive in three major categories: lesser apes (ex: gibbons), great apes (ex: gorillas), and humans. The morphology (physical structure) of hominoids varies, but they all share some common anatomical features. Genetics is important in understanding the biology of hominoids, including their immune system, DNA, and proteins. Biochemical and physiological relationships between hominoids are complex and vary depending on the species.

The Anatomical Advantages of Hominoid Shoulders and Limbs

Hominoids have an anatomy that allows them to easily raise their arms above their head. Larger and longer arms than monkeys are common among hominoids. The shoulder joint is very flexible and capable of wide-angle movement in hominoids. Hominoid shoulder blades are located more toward the back and face outward Modern humans are the exception to this role, with longer legs than arms. Apes' longer front arms allow for hanging from branches. Hominoid shoulder blades are long enough to allow for hand-holding, with a disc joint between the lower arm bones and wrist bones which cuts down on contact between the bones and increases flexibility.

Gorillas: An Overview of Their Social Structure and Environment

Largest living primates are gorillas. Adult males weigh 350 pounds and females weigh 155 pounds. Males have a large crest of bone on top of their skulls for anchoring their jaw muscles. Blackish haro, but fully mature males have silver hair on their backs (hence the moniker silver back male). Largely terrestrial, as gorillas are mostly because of their size. Gorillas must spend most of the day eating due to their large size and vegetarian diet.85% of the diet leaves their bodies, with special intestinal modifications to digest leaves.

Re-Classifying Lemurs, Lorises, and Tarsiers

Lemurs and tarsiers share some biochemical and genetic differences, as well as some characteristics (like moist noses). Some researchers propose a new classification of lemurs and tarsiers, which divides them into two groups based on these differences.

Exploring the World of Old World Monkeys

OWMs are quadrupeds that are agile and spend time on the ground in search of food. OWMs are biologically and physically more similar to human beings than NWMs. OWMs have a more varied social structure, ranging from group to group, possibly due to the availability of food.

The Fascinating World of Orangutans

Reddish brown hair Large sexual dimorphism with males 2x the size of females (175-200# vs. 73-100#) Males have large pads on their faces Agile climbers and hangers Climb with arms and legs in a slow cautious manner Young oranges may brachiate Largely arboreal but males frequently travel on the ground by first walking Produce spring more slowly than the other great apes Birth interval is 7.7 years (versus 5.6 for chimpanzees, 37 for gorillas, and often less for humans) Neither humans nor orangest have estrus (a distant mating cycle where females are receptive at specific times during the month) Social structure: Solitary social groups consisting of mother and infant Little danger of predators, so males are not needed for protection Adult males live by themselves, interacting only by mating Oranges are polygamous and don't form term bonds with single partners Not enough food to support large groups Environment: Found only in Borneo and Sumatra Live in tropical rainforests Oranges are vegetarian: 60% of the diet is fruits Fossil organs are found more widely throughout Asia going back 12 mya B.P. Climatic change and human altering of the environment have reduced the oranges to their present restricted range

What are some of the distinguishing features of strepsirrhines?

Strepsirrhines are distinguished by their lack of one or more of the general characteristics of primates, such as color vision or having a single claw on a hand or foot; their reliance on smell more than anthropoids; their smaller brains relative to body size than anthropoids; their generally smaller size than Haplorhines (anthropoids); and their variable body size, social group size, and activity patterns (some are diurnal).

Tarsiers: Closer Relatives to Monkeys and Hominoids?

Tarsiers are more closely related to monkeys and hominoids because they lack the wet nose associated with improved smelling ability that lemurs and lorises have.

The Loudest Mammal on Earth: Howler Monkeys (example of NWM)

The Howler Monkey is a genus of six species from South America. The Howler Monkey has a large hyoid bone in the throat which creates a large resonating chamber capable of making sound that can be heard many miles away. They are the loudest mammal on earth. Howlers have prehensile tails, eat fruit and leaves, and adults weigh 13-18 pounds. They are sexually dimorphic. Howlers live in multimale/multifemale groups of 6-20 individuals. There are also some uni-male howler groups. Howling for warning and defense against competitors and predators, instead of active fighting, is common. Howler territories often overlap substantially.

Exploring the Differences Between Strepsirrhines and Haplorhines

The Strepsirrhini is the suborder of primates that contains the infraorder Lemuriformes which contains the families Leuroidea and Lorisoidea. The Strepsirrhini includes lemurs and lorises.

What are the different types of strepsirrhines?

The different types of strepsirrhines are lorises, lemurs, and galagos. - Lorises are small solitary nocturnal prosimians found in Asia and Africa with moist noses for a keen sense of smell. - Lemurs are the most variable of the prosimians and all living lemurs are from Madagascar. They vary in social structure from animal to multi-male/multi-female and vary in body size, diet, and group size. - Galagos are small primates found in Africa and are also known as bushbabies. They have large eyes and ears, long tails, and are nocturnal

What are the distinguishing features of the tarsier?

The distinguishing features of the tarsier are its large eyes, lack of a moist nose, and its classification as a primate closer to monkeys than lorises. They are small solitary nocturnal primates found in Indonesia

Exploring the Suborder Haplorhini: Tarsiiformes, Platyrrhini, and Cararrhini

The haplorhines are a suborder of primates which contain the infraorder Tarsiiformes, Platyrrhini and Cararrhini

What are the differences between the higher primates and other primates?

The higher primates are generally larger in overall body size and have a larger relative brain size and complexity than other primates. They rely more on visual abilities and have more complex social structures than other primates. They are all diurnal and are found in both the New World and the Old World. The New World haplorhines are all monkeys, while the Old World haplorhines include monkeys, apes, and humans. The higher primates also have an infraorder Tarsiiformes which contains the tarsiers, and an infraorder Platyrrhini (New World anthropoids) which contains the superfamily Ceboidea (New World monkeys).

What are the controversies over the precise order of the splits between the great apes and humans?

The main controversy over the precise order of the splits between the great apes and humans is the exact timing of the split. While Sarich and Wilson's 1969 study suggested that the split occurred roughly at the same time, other studies have suggested that the split may have occurred at different times, with some suggesting that the split between humans and chimpanzees occurred earlier than the split between humans and gorillas. Additionally, some studies have suggested that the split between humans and bonobos may have occurred earlier than the split between humans and chimpanzees.

What are the differences between lemuriformes and tarsiiformes?

The main difference between lemuriformes and tarsiiformes is that lemuriformes include the lemurs (Lemuroidea) and the lorises (Lorisoidea), while tarsiiformes are a separate group, less closely related to either of the lemuriformes. Additionally, all strepsirrhines are found in the old world (Africa, Asia, and Europe), while tarsiiformes are only found in the new world (North and South America).

What are the differences between the infraorder Caatarrhini and the superfamily Cercopithecoidea?

The main difference between the infraorder Caatarrhini and the superfamily Cercopithecoidea is that the infraorder Caatarrhini contains both old world monkeys (Cercopithecoidea) and apes and humans (Hominoidea), while the superfamily Cercopithecoidea only contains old world monkeys.

What are the differences between monkeys and apes?

The main differences between monkeys and apes are their physical characteristics. Monkeys have tails, while apes and humans do not. Monkeys also have smaller brains relative to body size than apes or humans. Monkeys typically move as quadrupeds, with arms and legs of similar length, keeping the spine parallel to the ground. Apes and humans, on the other hand, have longer legs than arms.

What are the most important differences between New World Monkeys and Old World Monkeys?

The most important differences between New World Monkeys and Old World Monkeys are their dental formula, the presence of prehensile tails in New World Monkeys, and the lack of prehensile tails in Old World Monkeys. New World Monkeys have four more premolars than Old World Monkeys, and most New World Monkeys have a dental formula of 2-1-3-3, while all Old World Monkeys have a dental formula of 2-1-2-3. Additionally, New World Monkeys have prehensile tails, which are adapted for arboreal life, while Old World Monkeys do not have prehensile tails. It is unclear whether the prehensile tail is a primitive or derived trait.

How does the suspensory climber's ability to hand-over-branches compare to a jumper's ability to move onto the branches?

The suspensory climber's ability to hand-over-branches is much more efficient than a jumper's ability to move onto the branches. Suspensory climbers can raise their arms above their heads and use their hands to grip onto the branches, allowing them to climb up with greater ease and stability than a jumper could. This makes suspensory climbing a much more efficient and effective way of moving through the trees.

What are the two major subgroups of primates?

The two major subgroups of primates are Prosimii (Beforesimians) and Anthropoidea (anthropoids). Prosimii (Before simians): biologically primitive primates compared with anthropoids Anthropoidea (anthropoids): the suborder of primates consisting of monkeys, apes, and humans