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Why study Diet?. Utility for model building?. Food provides energy necessary to sustain life and allow for reproduction. Main activity of most animals’ lives. Major component of natural selection: “obtain food and keep from becoming food”. Why study teeth?. Utility for model building?.
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Why study Diet? Utility for model building? • Food provides energy necessary to sustain life and allow for reproduction • Main activity of most animals’ lives • Major component of natural selection: “obtain food and keep from becoming food”
Why study teeth? Utility for model building? • Indicate foods consumed • Indicate size & behavior • Well preserved in the fossil record • Growth & development patterns • Sexual dimorphism characteristics • Non-dietary indicators
Tooth Types Human Dentition
Roles of the teeth Differential use in heterodont dentition Incisors & canines -- • ingestion, get the food into the mouth • seizing, stripping, squashing, puncturing Premolars & molars -- • preparation of food for digestion • food is chopped up to increase surface area • molars are a series of cutting blades and crushing basin
Extant vs Extinct Data collection from the living primates
Diagnostic features Features of the skull used to determine dietary category • Incisors & canines • Molars & premolars • Cusps & crests • Enamel thickness • Massiter & temporalis muscles • Body size
Large incisors indicate • frugivore • Small incisors = carnivore • or insectivore Incisors & Canines Anterior Dentition • Get food in the mouth • Grooming • Scraping • ~~~~~~~~~~~~~~~~~~~~
Premolars & Molars Posterior Dentition • Folivores = low or high • Insectivores = tall, pointed • Carnivores = tall, pointed • Frugivores = low, rounded • Omnivore = low, rounded
Premolars & Molars Premolars& Molars
Cusps & Crests Molar & premolar morphology cusp crest
Enamel thickness Thickness of the hard mineral surface covering the teeth
Dental Attrition Enamel wear
Body size Diet dictates primate body size • Body-size tends to • correlate w/ dietary • regime • Folivore = largest • Insectivore = smallest • Frugivore = medium to large
Dietary strategies Categories of Diet for the Primates • Folivore - plants • Frugivore - fruit • Carnivore - meat • Insectivore - insects • Omnivore - mixed
Folivores Consumes plant products; stems, leaves, shoots, roots • Low rounded cusps and crests • Comparably sized incisors & canines • Thin enamel • Strong massiter muscles • Larger body size • Special adaptations -- multi-chamber stomach • Requires supplementation -- dirt, feces, etc.
Folivores Consumes plant products; stems, leaves, shoots, roots
Frugivores Consumes fruit, seeds, nuts • High percentage of fruit; rich carbs, low protein • Large incisors • Thin enamel • Diet needs supplementation, leaves, soil, etc. • Larger body size • Canine size usually results from dimorphism
Frugivores Consumes fruit, seeds, nuts
Frugivores Consumes fruit, seeds, nuts
Carnivores Consumes animal protein, requires little supplementation • Very high in protein • Consumes little else to aide in digestion • Plants/grasses • Long canines; small incisors • Sharp cusps & crests • Thin enamel • Large temporalis, small massiter
Carnivores Consumes animal protein, requires little supplementation
Insectivores Consumes insects • Small sized primates • High protein, but in small packets • Large canines • Sharp cusps & crests • Diet needs supplementation
Insectivores Consumes insects
Omnivores Consumes a variety of food resources • All teeth of similar size • Moderate enamel thickness • Low cusps, dull crests • Comparably-sized temporalis & massiter • Dental reduction • Facial reduction
Omnivores Consumes a variety of food resources
Quiz Name the Dietary category for each skull