ANTH 3000 exam 1

What are the key taxonomic traits of Strepsirrhines?

Moist rhinarium, toothcomb, grooming claw, reflective tapetum (for night vision), mostly nocturnal.

How does olfaction differ between strepsirrhines and haplorrhines?

Strepsirrhines rely heavily on smell (scent marking, grooming); haplorrhines rely more on vision.

Name an example of nocturnal lemurs and their locomotion.

Mouse lemur – vertical clinging and leaping.

How do diurnal lemurs differ from nocturnal lemurs?

Diurnal lemurs are more social, live in larger groups; nocturnal lemurs are mostly solitary and smaller-bodied.

Key differences between lorises and lemurs?

Lorises: Asia, slow climbers, nocturnal, toxic bite; Lemurs: Madagascar, diverse activity patterns, mostly diurnal.

What is adaptive radiation in Madagascar lemurs?

Diversification into many ecological niches due to isolation; examples include bamboo lemurs (specialized folivores) and aye-ayes (percussive foragers).

Name the diurnal lemur families.

Indriidae (Indri, Propithecus), Lemuridae (ring-tailed lemur, bamboo lemur).

What traits help haplorrhines occupy the diurnal niche?

Trichromatic vision, larger brains, reduced reliance on smell, post-orbital closure.

Where are haplorrhines found?

Africa, Asia, Central and South America.

Major differences between strepsirrhines and haplorrhines?

Haplorrhines = diurnal, color vision, larger brains, complex social systems; Strepsirrhines = nocturnal, rely on smell, smaller brains.

Are tarsiers strepsirrhines or haplorrhines? Why?

Haplorhines – they have post-orbital closure and no toothcomb.

Unusual adaptations of tarsiers?

Giant eyes (no tapetum), faunivorous diet, vertical clinging and leaping.

What are derived specializations of Callitrichidae (marmosets & tamarins)?

Claws for climbing, incisors for gum feeding, twinning, communal care.

How does small body size affect marmosets and tamarins?

High metabolic rate, small home ranges, cooperative caregiving.

Dental adaptations of Saki and Uakari monkeys?

Large robust teeth for cracking seeds and hard fruits.

How do capuchins use teeth differently?

Capuchins use tools to crack hard nuts rather than specialized teeth.

Which New World monkeys have prehensile tails? Why?

Atelines (spider monkeys, woolly monkeys, howlers) – for arboreal locomotion and suspensory feeding.

What is fission-fusion social structure?

Groups split and merge dynamically depending on food availability.

Key differences between platyrrhines and catarrhines?

Catarrhines: downward nostrils, 2.1.2.3 dental formula, no prehensile tail; locomotion includes terrestrial quadrupedalism.

Colobinae vs Cercopithecinae?

Colobinae = sacculated stomachs, folivores, arboreal; Cercopithecinae = cheek pouches, frugivores/omnivores, terrestrial or arboreal.

Characteristics of terrestrial Cercopithecinae?

Larger bodies, sexual dimorphism, ischial callosities, less arboreal than guenons.

How do colobines digest leaves?

Sacculated stomachs with foregut fermentation.

Differences between monkeys, apes, and humans?

Monkeys: tails, pronograde, narrow chest.
Apes: no tails, orthograde, wide ribcage, suspensory locomotion.
Humans: bipedal, S-shaped spine, pelvis adapted for upright walking.

Locomotor differences in apes?

Gorillas/chimps = knuckle-walking, orangutans = quadrumanous climbing, gibbons = brachiation.

Social organization differences: Hylobatidae vs Hominidae?

Hylobatidae = monogamous pairs; Hominidae = varied (gorillas polygyny, chimps fission-fusion).

Anatomical differences in ribcage, scapula, spinal column between apes and monkeys?

Apes = broad shallow ribcage, dorsal scapula, flexible spine; monkeys = narrow deep ribcage, lateral scapula, less flexible spine.

Convergent evolution?

Independent evolution of similar traits in unrelated species (e.g., aye-aye vs woodpecker foraging).

Sexual dimorphism & sexual selection?

Dimorphism = physical differences between sexes; selection = traits evolve due to mate choice or competition.

Comparative method?

Comparing species to infer evolutionary patterns.

Sperm competition? Example?

Competition between males’ sperm; e.g., chimps have large testes due to multi-male mating.

Adaptive radiation? Example?

Rapid diversification into ecological niches; Madagascar lemurs.

Pre-adaptation? Example?

Trait evolved for one purpose, later useful for another; e.g., arboreal limbs later used for brachiation.

Fission-fusion

Dynamic social groups that split/merge based on resources or context.

Trichromatic vision

Color vision with three photopigments; common in diurnal haplorrhines.

Vertical clinging and leaping

Locomotion strategy: cling to vertical supports, leap to next tree.

Quadrumanous

Using all four limbs for grasping in locomotion (orangutans).

Ischial callosities

Hairless pads on buttocks of some OW monkeys for sitting.

Sacculated stomach

Multi-chambered stomach for leaf fermentation (colobines).

Sectorial premolar

Premolar adapted to sharpen canine (OW monkeys, male competition).

Grooming claw & toothcomb

Specialized Strepsirrhini traits for grooming and scraping food.