Introduction to Primates

Question 1

Are primates an order of mammals?

Answer 1

Yes, they have mammalian synapomorphies (warm blooded, viviparity, lactation and mammary glands).
These traits are primitive because primates share them with last common ancestor and with all other mammals

Question 2

What are primate characteristics?

Answer 2

Grasping hands and feet, sensory system, large complex brains, dental specializations but generalized skeletons

Question 3

Describe the primates’ grasping hands and feet.

Answer 3

Opposable thumb (pollux) and hallux (big toe), nails NOT claws, sensitive tactile pads, power grip, precision grip

Question 4

Describe the sensory systems in primates.

Answer 4

Forward facing eyes (stereoscopic vision (vision overlaps), depth perception), greater reliance on vision, colour vision

Question 5

What are the two types of colour vision in primates?

Answer 5

• Most are at least dichromatic (blue, green)
• Many are trichromatic (red, blue, green)

Question 6

What type anatomy protects the eye?

Answer 6

All primates have at least postorbital bar, haplorhines have a postorbital closure

Question 7

Do non-primates have protective cranial anatomy?

Answer 7

No, most non-primates have a postorbital process which is just a hole where the eye is; it is not protected

Question 8

What does the increased reliance on vision affect?

Answer 8

There is reduced reliance on Olfaction (scent). Which leads to the reduction of the snout (more extreme in haplorrhines) and olfactory centres of the brain (smaller in primates than in other animals)

Question 9

Do primates have large brains?

Answer 9

Yes, they have large brains relative to body size. It has many folds (sulci and fissures) to increase surface area

Question 10

Why do primates have such large brains?

Answer 10

Great emphasis on learning and socialization for survival. This reliance on learning reduces reliance on instinct

Question 11

Explain primate offspring

Answer 11

Primates usually have high investment in their offspring. Typically give birth to one child that is longer lived, infants are usually altricial (helpless at birth), usually cling to the mother (really small primates leave their infants in nests), longer juvenile development

Question 12

What is the difference between a group and a herd?

Answer 12

A herd just travel together, a group has socialization occurring within (primates)

Question 13

What are the 4 types of teeth?

Answer 13

Incisors, canines, pre-molars, and molars in that order

Question 14

What are the dental formulas of primates?

Answer 14

Ancestral mammal: 3.1.4.3

Primitive primates (most strepsirhines): 2.1.3.3

Later primates: 2.1.2.3

Question 15

Do dental formulas tie to diet?

Answer 15

Yes

Question 16

Do primates have a specialized skeleton like their teeth?

Answer 16

No, primates have pretty basic skeletal morphology. It hasn’t changed much from millions of years ago

Question 17

Do all primates have the characterized traits?

Answer 17

No (ex: humans don’t have grasping toe). None of these traits are unique to primates either, but the suite of traits is unique to primates

Question 18

What is our taxonomic classification?

Answer 18

Kingdom animalia, phylum chordata, class mammalia, order primates, family hominidae, genus homo, species sapiens

Question 19

What are Strepsirrhines and where are they found?

Answer 19

Lemurs, galagos, lorises. They are found in sub-saharan Africa, Madagascar, and Asia

Question 20

What are characteristics of Strepsirrhines?

Answer 20

• All primate characteristics
• Nocturnal (big eyes allow more light in to see at night)
• Rely more on scent marking (olfaction)
• Dental comb (incisors and canine on bottom jaw are modified to look like a comb to use for grooming)
• Grooming claw on 2nd digit of foot (used in grooming)

Question 21

What are the two subcategories of Strepsirrhines?

Answer 21

Lemuriformes and Lorisiformes

Question 22

What are Lemuriformes?

Answer 22

Only found in Madagascar and Comoros Islands (endemic to that part of the world), very diverse cause of adaptive radiation, endemism, and lack of competition, small/medium sized today but bigger in the past, diurnal and nocturnal, female dominance, 5 families

Question 23

What are Lorisiformes?

Answer 23

All nocturnal and small bodied, solitary or in small family units, eat insects, gum, nectar, and same fruits. Two families: galagidae (active fast movers from Africa) and lorisidae (often immobile slow movers from Africa and Asia).

Question 24

What are Haplorrhine characteristics?

Answer 24

Diurnal (except tarsiers and owl monkeys), reduced reliance on smell and hearing (flatter faces, shorter snouts), larger/complex brains (longer juvenile dependancy, more parental care, more social complexity

Question 25

What are the Tarsiiformes?

Answer 25

The tarsiers are the only living genus in this category. Primitive morphology, superficially look like strepsirrhines but genetically are haplorrhines

Question 26

What are the infraorders of haplorrhines?

Answer 26

Tarsiiformes, Platyrrhini, Catarhhini

Question 27

What are higher primates/Anthropoidea?

Answer 27

Platyrrhini and Catarrhini

Question 28

Why are they called Platyrrhini?

Answer 28

Broad outward facing nostrils and 2.1.3.3 dental formula

Question 29

What are they called Catarrhini?

Answer 29

Narrow downward facing nostrils and 2.1.2.3 dental formula

Question 30

What are characteristics of Platyrrhini?

Answer 30

Monkeys that lived in the americas, all have tails (many have prehensile tails (strong enough to hang from)), arboreal (live in trees), smaller bodies than cercopithecoid monkeys, most have 2.1.3.3 formula, minimal sexual dimorphism, diurnal (except owl monkey)

Question 31

What are the subdivisions of Catarrhine?

Answer 31

Cercopithecoid monkeys and hominoidea apes

Question 32

Characteristics of superfamily Cercopithecoidea?

Answer 32

Widest distribution in environments, all diurnal, single births, some terrestrial species, larger body size, sexually dimorphic

Question 33

What are the subfamilies of Cercopithecoidea?

Answer 33

Cercopithecinae (fruit eaters, broad incisors, low cusps, cheek pouches, simple stomach, shorter limbs)

Colobinae (leaf eaters, narrow incisors, high cusps, no cheek pouches, complex stomachs, long limbs

Question 34

Describe the subfamily Cercopithecinae.

Answer 34

Africa and Asia and are widely distributed, diet variable, variable social systems, most are sexually dimorphic, more terrestrial species than any other group

Question 35

Describe the subfamily Colobinae.

Answer 35

Africa and Asia, smaller, all arboreal, specialized folivores (sacculated stomach that supports bacteria for digestion of cellulose and high shearing crests on teeth)

Question 36

What are the characteristics of the superfamily Hominoidea?

Answer 36

Apes, no tails, larger size and weight, larger brain to body weight ratio, upright posture, longer gestation and maturation

Question 37

What are the characteristics of family Hylobatidae?

Answer 37

“lesser apes”. Southeast asia, frugivores, sexually monogamous, move using brachiation (aerial phase), highly territorial

Question 38

What are the characteristics of Hominidae?

Answer 38

Large bodied, suspensory locomotion in trees (not brachiation), knuckle walking, sexually dimorphic, advanced cognitive abilities, diverse diets and social systems, investments in offsprings