Lab Quiz #2 Study Guide

mammary gland

a milk-producing gland in female mammals

terrestrial

living on the ground

arboreal

living in trees

nocturnal

active primarily during the night hours

diurnal

active primarily during the daylight hours

uniparous

producing one offspring at a time

opposable digit

a thumb or big toe capable of being positioned opposite the other digits, which confers the ability to grasp objects

forward-facing eyes

eyes that are positioned at the front of the face and point directly ahead

post-orbital bar

a bar of bone that sits lateral to the eye but does not fully enclose the eye in a bony pocket

rhinerium

a damp pad at the end of the nose

dental comb

a tooth structure made of elongated and closely positioned lower incisors and canines that project out from the front of the face

unfused mandible

a mandible made of two separate bones that are attached by cartilage along the midline

mandibular symphysis

the area where the two sideds of an unfused mandible are attached by cartilage

New World

a name traditionally assigned to the American continents

Old World

a name traditionally assigned to the majority of the non-American continents, specifically Africa, Asia, and Europe

septum

the soft tissue between the nostrils

prehensile tail

a tail with the ability to grasp objects and act like a fifth limb

bilophodont molar

a molar with four cusps arranged in two parallel ridges (or lophs)

ischial callosity

a roughened patch of skin located in the ischial area (on the buttocks)

cheek pouch

a pouch in the cheek and neck area that can expand to store food

Y-5 molar

a molar in the lower dentition that has 5 cusps positioned such that a pronounced Y-shaped groove forms between the cusps

orthognathic

having a flat face

prognathic

having a projecting/protruding face

gracile

having thin, light musculature & bone

robust

having thick, dense, heavy musculature and bone

dish-shaped face

a somewhat concave face formed by a sloping upper face and protruding lower face

insectivory

a diet that emphasizes insects

• have molars with pointy cusps and a simple digestive system

• food is surrounded by thin crunchy layer

• ex: chimpanzee

gummivory

a diet that emphasizes tree gums (or sap)

• small body size

• food is trapped behind tough tree bark

• dental comb

• ex: tarsier

folivory

a diet that emphasizes leaves (foliage) and other plant parts

• have molars with sheering crests & a complex stomach

• food is tough & fibrous

• ex: gorilla

sagittal crest

a ridge of bone along the midline of the cranium that allows for the attachment of extra-large chewing muscles

frugivory

a diet that emphasizes fruit

• food is soft & needs to be gently pulped

• round cusps

• ex: lemur

locomotion

an animal’s form of movement in traveling from one place to another

forelimb

the upper or front limb (commonly called the arm)

hind limb

the lower or back limb (commonly called the leg)

vertical clinging & leaping

a form of locomotion where the body is oriented vertically and movement occurs by leaping from tree to tree

suspensory locomotion

a form of locomotion where the body is suspended (for hanging) below tree branches

brachiation

a form of suspensory locomotion where movement occurs through arm-over-arm swinging

• long arms

• mobile shoulders

• robust finger bones

semibrachiation

a form of suspensory locomotion where movement occurs through the use of the arms and a specially adapted prehensile tail, which can grasp tree branches

quadrupedalism

a form of locomotion that uses all four limbs

arboreal quadrupedalism

a form of quadrupedalism that is practiced in the trees

terrestrial quadrupedalism

a form of quadrupedalism practiced on the ground

• similar length of arms & legs

• robust hands & feet

• short tail

knuckle-walking

a form of terrestrial quadrupedalism that involves walking on the knuckles of the hands

intermembral index

a ratio of forelimb length to hind limb length that is often used to quantify locomotor adaptations

sexual dimorphism

the physical differences between adult males and females of a species

• most common in single-male polygnous groups

verbate monkey

• scapula: side

• intermembral index: 80-100

• tail: prehensile

• locomotion: arboreal quadrupedalism

gibbon

• scapula: back of the rib cage

• intermembral index: 100-150

• tail: n/a

• locomotion: brachiation

human

• scapula: back of shoulder

• intermembral index: <100

• tail: n/a

• locomotion: bipedal

lemur

• scapula: back of shoulder

• intermembral index: 50-80

• tail: small

• locomotion: VCL

chimpanzee

• scapula: ribs

• intermembral index: 80-100

• tail: small

• locomotion: quadrupedalism