Primate Diversity COMPLETE SUMMARY

Primate Diversity and Evolution (Module 5)
OVERVIEW OF PRIMATES

WHAT IS A PRIMATE?
• Kingdom = Animalia
• Phylum = chordata
• Class = mammalia
• Order = primates

• Very diverse group of mammals —> lots of species (600+)

PRIAMTE HABITATS

• The tropics —> most extant forms
• Used to live in northern europe (more tropical in the past

• Primary and secondary rainforest
• Gallery forest
• Woodland
• Savannah — eg. Chacma baboons

HABITAT USE

• Why live and evolve in tropical rainforest initially?
• Provision of elements that are linked to their adaptations
• Primates move across trees and not just across a at plain
• Can move through complicated environments very quickly
• Emergent trees
• Main canopy
• Understory

ANCESTRAL MAMMALIAN TRAITS

• Generalised mammal body plan
• Eg. Four limbs + tail
• Retention of clavicle —> allows for exibility + movement in environments
• Relatively exible joints in forelimbs
• Pentadactyly ( ve ngers)
• Generalised heterodont dentition
• No highly specialised teeth —> widely varied diet

DERIVED PRIMATE TRAITS

• Grasping hands + feet w/ protective nails
• Sensitive pads, opposable thumb = can touch the ventral surface of the tip of all four ngers
to the ventral surface of the thumb of the same hand
• Allows for grasping “power grip"
• Skin ridges on knuckles —> dev into human ngerprints
• All primates except humans have divergent big toe for grasping
• Stereoscopic binocular colour vision
• Decreasing reliance on smell
• Superior dexterity and muscle coordination
• Bony ear
• Retention of clavicle
• Relatively large brain and complex social structure




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, PRIMATE DIETS

• Origins of primates are in a rainforest environment
• Combined with heterodonty…
• Diverse range of diets
• Frugivory
• Folivery
• Grammivory
• Gramnjivory
• Insectivory

• Mutation has occurred that means that primates lack a gene for creation of vitamin C
• As such.. need to ingest it and get it from their diet
• Invisible to natural selection in those species living in rainforests where there is an abundance
of fruit and vegetables
• Became evident in humans during travel and exploration (scurvy outbreaks)


PRIMATE LOCOMOTION

• Bipedalism
• Humans = only to evolve bipedalism!
• Arboreal quadrupedalism
• Leaping
• Long bodied in order to spring between branches
• Terrestrial quadrupedalism
• Come out of a tree environment
• Larger bodied in order to cope with largely terrestrial existence
• Suspension
• Mobile shoulder joints


PRIMATE BEHAVIOUR AND LIFE HISTORY

• Emphasis on learning
• Group living
• Intelligence = important
• Long life history stages —> extended period of infant development, juvenile and adolescent
stages
• Important for neutron development!
• Longer time spent learning = stronger connections and social connections are laid down
for adulthood
• Strong mother-o spring bonds
• O spring are largely helpless at birth
• Single births (or twins)
• Kinship = important

• Reproductive strategy is that of investment in the o spring to ensure success

SEXUAL DIMORPHISM

• Tied to the social organisation and reproductive strategies of primates
• Monomorphic = similar size and appearance between males and females often suggests
monogamy
• Humans are NOT monomorphic but are not largely dimorphic!! —> move towards an
egalitarian existence
• Dimorphism = diverse appearances between males and females —> largely polygamous
reproductive strategy




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, • Sexually dimorphic traits =
• Body size
• Large canines
• Facial colouring
• Manes
• Check pads

PRIMATE (order) SUBORDINAL TAXONOMY

SUBORDER STREPSIRRHINI SUBORDER HAPLORHINI


• Rhinarium —> structure to the nose • No rhianrium
that keeps it moist
• Strepsirrhines are relatively more • Continuous upper lip
olfactory sense orientated
• Split upper lip • No tapetum lucidum

• Tapetum lucidum —> structure of the • Post orbital plate or enclosure
eye to assist with night vision
• Mostly nocturnal animals
• Post orbital bar • Separation of eye socket from muscles of
mastication + protection from mechanical
damage
• Tooth combs • No tooth combs
• Incisors that are reduced and made
pointier in order to groom

SUBORDER STREPSIRRHINI

CHARACTERISTICS =
• Rhinarium —> structure to the nose that keeps it moist
• Strepsirrhines are relatively more olfactory sense orientated
• Split upper lip
• Tapetum lucidum —> structure of the eye to assist with night vision
• Mostly nocturnal animals
• Post orbital bar
• Tooth combs
• Incisors that are reduced and made pointier in order to groom

1. Infraorder lorisiformes

• SE asia and africa
• Small
• Solitary
• Nocturnal
• Largely arboreal
• Eg. Bush baby

2. Infraorder lemuriformes

• Madagascar and nearby islands
• Adaptive radiation
• Variable size and behaviour —> islands = adaptive laboratories!! = create great diversity
• Eg. Recently extinct megaladapis was roughly the size of a gorilla (~200kg)
• Variable dental formulae