Anthropology 2200 OSU Exam 2
Versatile Skeletal Structure - Opposable Pollexes - using your thumbs to grab things, Opposable halluxes (except humans), Greater range of motion in backbone. - Orthograde posture - upright posture. Enhanced sense of touch. - Dermal ridges (fingerprints), Nails instead of claws. Enhanced vision - Forward facing eyes, Color vision, Post-orbital Bar All primates have a post-orbital bar (behind the eye) Higher Primates have a Post-orbital bar with closure. Reduced reliance on smell and hearing - Loss of rhinarium - Reduced snout size
Arboreal Adaptations
the Most specialized of all primates - Continuously growing incisors - No toothcomb - Secondarily evolved claws (very rare, evolved claws after evolving nails) - Percussive foraging o Elongated middle digit - Large dish-like ears - Nocturnal - Large brain, larger than any other Strepsirhini
Aye-Aye Features
Female reproductive success limited by access to food. Male reproductive success limited by access to females.
Bateman's/Triver's Principle
Likely ancestor to euprimates (transitional species) Characteristics: - Opposable pollex and hallux - One nail - Long, grasping fingers
Carpolestes
Old World Monkey - Africa & Asia - Arboreal and terrestrial species - Bilophodont molars ( four points) - Ischial callositites (sitting pads) on the butt to protect it. - Tails (non-prehensiles) - Two Families. o Cercopithecines - • Frugivorous (Fruit eating) - Cheek-pouch monkey • Arboreal - Long tails • Terrestrial - Short tails o Colobines • Folivorous (leave eating) - Large multi-chambered stomach • Long-tails • Wide array of coloration • Arboreal
Catarrhines
• Frugivorous (Fruit eating) - Cheek-pouch monkey • Arboreal - Long tails • Terrestrial - Short tails
Cercopithecines
• Folivorous (leave eating) - Large multi-chambered stomach • Long-tails • Wide array of coloration • Arboreal
Colobines
Learned behavior that is socially transmitted, often involves tool use. Examples: Food Washing - Japanese Macaques Nut Cracking - Chimpanzess, Capuchins Termite Fishing -Chimpanzess, Orangutans Water play & Swimming - Multiple Species Hot Springs - Japanese macaques Playing with Snowballs - Japanese macaques Making Tools - Chimpanzees, Orangutans, gorillas, capuchins, macaques. Food acquisition tools. Examples - spear fishing, checking the depth of water. Medicine- - Insect Repellant - Capuchins - Geophagy - Chimpanzees, colobus monkey, howler monkeys, muriquis. Eating soil to calm down their stomachs. - Plants for Parasitic Infections - Chimpanzees, muriquis. Spirituality? - The Waterfall Dance - Only chimpanzees at Gombe
Culture in Primates
The ability to eat various foods
Dietary Plasticity
An intentional way to display dominance. Example: When A walks over to B and B will move because A is dominant.
Displacement
- Found in some primate species - Males and Females - Males usually dominant over females - Dominance has both costs and benefits
Dominance Hierarchies
India & Asia collide to form Himalayan and East African Mountains Climate becomes cooler and dryer Most Asian apes go exinct Khoratopithecus moves south, evolves into extant organgutans Most European apes go extinct - Some migrate south, back into Africa - Adapt to either woodlands or grasslands. OWM undergo adaptive radiation and fill open niches
End of the Miocene
Characteristics - Sexual dimorphism - Long opposable digits - Non-specialized teeth - Increasing brain size - Nails - Post-orbital bar Behavioral Trends - Complex social organization - Increased reliance on vision and manipulative abilities - More acrobatic locomotion Adapids - North America - Diurnal - Reduced prognathism - Slightly larger brain - More forward facing eyes - Dental formula: 2-1-4-3 - Molars with shearing crests - Some species had fused mandible - Possibly lemur ancestor Omomyids - North America - Nocturnal - Partial Post-Orbital closure - Large, Projecting incisors - Small canines - Decreased prognathism - Possibly tarsier ancestor
Euprimates
Eosimias - China - ~45 MYA - Ankle bones suggest Eosimias moved in trees like a monkey Archicebus Achilles - Discovered August 2013 - China - 55 MYA (oldest primate) - 2.8" long, 1 oz - Diet: insects, fruit - Diurnal - Possible link between tarsiers and anthropoids
Fossils in support of anthropoids being as old as strepsirrhines
Infanticide conditions: - Male is not father - Female mates with infanticidal male - Shortens interbirth interval Infanticide defenses: - Promiscuity - Faking estrus - Aggressive defense
Infanticide
- Facial expressions - Grooming - communicates friendship - Displacement - intentional way to display dominance. Example: When A walks over to B and B will move because A is dominant. - Vocalizations o Food association. Almost like naming. o Offspring association o Warning calls o Grunts and threat grunts o Territory o Mate Location o Whispering? - Sign Language - Lexigrams
Intentional Communication
Arboreal Locomotion Vertical Cling & Leaping - Intermemberal Index ~ 70 Arboreal Quadrupedalism - Intermembral Index ~ 80 Suspensory Locomotion - Intermembral Index ~110-130 Brachiation - Intermembral Index ~130 Terrestrial Quadrupedalism - Intermembral Index ~ 80 - 100 Knuckle-Walking - Intermemberal Index ~110 Bipedalism - Intermembral Index ~ 70 - Humans and birds are the only obligate bipeds. Other Primates are facultative bipeds
Intermembral Index
Primates weighing less than 500g are usually insectivores or gumnivores, while primates over 500g tend to be either folivores or frugivores.
Kay's threshold
Capuchin
Most Intelligent NWM
- Victoriapithecids o Theropithecus oswaldi • Females ~175lbs • Males with very large cannies
Old World Monkey Ancestor
A second hypothesis suggests that after origination in Africa, the ancestors migrated across the Atlantic Ocean to South American - One of the possible Hypothesis A third hypothesis suggests that the African ancestors reached South America not by water but by land; they migrated to the southern tip of African, crossed Antarctica, and eventually reached the southern tip of South America - The other possible hypothesis
Origin of Platyrrhines Hypotheses
- Remaining with birth group - Mostly female philopatry - Incest avoidance
Philopatry
New World Monkey - Round nostrils, Wide nasal septum - Central and south America - Dental formula: 2.1.3.3 - Strictly arboreal (live and exist in trees) - Wide dietary ranges Atelids - Largest NWMs - Prehensile tails (the end of the tail is full of muscle) only primates with this type of tail. o Spider Monkey o Woolly monkeys o Howler monkeys - Pithecides
Platyrrhine
- Prognathic snout - Lateral orbits - No post orbital bar - Whiskers - Reliance on smell - Claws - Non-opposable digits - Solitary - Flat, rounded molars (The reason why we believe they are ancestors of primates)
Plesiadpiformes
To form relationships with other primate and non-primate species
Polyspecific Associations
- Arboreal Hypothesis - they developed so they can live in trees. Not generally accepted - Visual Predation Hypothesis - Primates evolved with traits that they have because they are visual predators. - Angiosperm Radiation Hypothesis - Primates evolved essentially to go after fruit in trees. Currently most accepted hypothesis.
Primate Evolution Hypotheses
Domain: Eukarya Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Primates - Two Suborders: o Haplorhini o Strepsirhini Over 200 species and 600 subspecies. Nonhuman Primate Distribution New World - Central and South America Old World - Africa and Asia
Primate Taxonomy
Acquiring Food, Predator Protection
Reasons for Living in Groups
Difference between male and females of the same species
Sexual Dimorphism
- Natural selection increases traits that improve reproductive success - Typically operates in males because reproduction based on female choice o Intersexual Selection • Between opposite sexes • Why are enhance features preferred by opposite sex? The reason that females go for these traits is to indicate how fit a male is. • Drives sexual dimorphism o Intrasexual selection • Between same sex • Competition for mates • Drives sexual dimorphism
Sexual Selection
To develop normally, primates need: - Parental Bond, - Physical Contact, - Social Learning. Without normal social development, primates may develop aberrant behaviors. - Self-Embracing - Self-injury - Eating Disorders - Sexual Disorders - Stereotypies - Repetitive motion for no reason. - Extreme Fearfulness - Extreme aggression - Rejection of Offspring
Social Development & Aberrant Behavior
One-male, multi-female (polygyny) - Some langurs, some howler monkeys, some OWM, and gorillas. One-female, multi-male (polyandry) - Males contribute to raising offspring - Rare, only in some NWM Multi-Male, Multi-female - Many are fission/fusion, splits up during the day into smaller sub groups but comes back during the night - Some NWM, many OWN (Chimpanzees) All Male - Baboons, gorillas, others. Are temporary and are sometimes called "bachelor groups" One male, one female (monogamy/pair bonding) - Males invest in parental care - Gibbons, owl monkeys, some strepsirrhines Solitary - Mostly interact for sexual activity - Orangutans, most strepsirrhines
Social Groupings
Ancestral (strepsirhine) Features: - Unfused mandible and frontal bones - Locomotive style - Grooming claw - Nocturnal Derived (haplorhine) features: - No rhinarium - No tapetum lucidum - Has bigger eyes than brain. - No tooth comb - Partial post-orbital closure Unique features: - Grooming claw on digits 2 and 3 - Only entire faunivorous (eat live prey, no fruits or leaves) primate
Tarsier Features
All great apes have Theory of Mind, the ability to be self aware
Theory of Mind
Arboreal Locomotion Vertical Cling & Leaping - Short forelimbs, Long hindlimbs - Used by Strepsirrhines and tarsiers Arboreal Quadrupedalism - Most common locomotor strategy for primates - Short limbs of equal length and long tails - Used by platyrrhines and many Old World Monkeys Suspensory Locomotion - Long Forelimbs, Short hindlimbs (opposite of VCL) - Used by many primates Brachiation - Type of suspensory behavior - Used by gibbons and orangutans Terrestrial Locomotion Terrestrial Quadrupedalism - Long limbs of equal length - Used by some catarrhines Knuckle-Walking - Type of terrestrial quadrupedalism - Forelimbs longer than hindlimbs - Used by great apes Bipedalism - Shorter forelimbs and hindlimbs - Humans and birds are the only obligate bipeds. Other Primates are facultative bipeds
Types of Locomotion & Associated Traits
- Increased Odor - Piloerection - Hair standing up. - Sexual Signals
Unintentional Communication