Skin & Derivatives + Teeth (Lab Week 1)

hair growth where hair is shed & replaced once a given length is reached

definitive

continuous hair growth

angora

total body covering of hair

pelage

long, stiff hair that serve as tactile receptors, e.g. whiskers

vibrissae

2 types of guard hair

awn & bristles

outer layer of hair on most mammals, exhbits definitive growth -- expanded distally, weakened basally

awn (most common type of guard hair)

firm hairs with angora growth, e.g. lion mane. May be stiff/enlarged such as spines/quills

bristles (less common type of guard hair)

2 types of underfur

wool & fur

long, soft often curly with angora growth underfur

wool

relatively short underfur, with definitive growth

fur

teeth with low rounded cusps for crushing molar power, found in omnivores

bunodont

shearing teeth, type of secodont (P4m1), found in carnivores

carnassials

serrated teeth for grinding vegetation 3rd premolar (PM3, pm3), found in marsupials

plagiaulacoid

Hypsodont or brachyodont?

hypsodont

homodont

selenodont

bilophodont

lophodont

Hypsodont or brachyodont?

hypsodont

selenodont

bilophodont

carnassial

euthemorphic

2 words to describe these teeth

bunodont & brachyodont

hypsodont

brachyodont

zalambdodont

dilambdodont

type of scales in mammals

epidermal

when young animals replace juvenile pelage with adult pelage

post-juvenile molt

molts that allow animals to replace hairs that are worn

annual molts

molts that allow variable fur characters in summer vs. winter

seasonal molts

horn-like structures within the skin that secondarily fuse to the skull; found in both sexes, remained furred in females, not males, ex: giraffe & okapi

ossicones

branched, solid bone, covered by velvet when growing, shed annually, found only in males (except female caribou)

antlers

section between the bases of the 2 antlers

burr

main branch of the antlers

mainstem

branches at the top of the antler

crown

tine on the antlers closest to the skull

brow tine

tine behind the brow tine

bez tine

living skin/fur on antlers

velvet

similar to horns, but with a prong & shed annually

also projection of frontal bone

may be found on both sexes but larger on males

pronghorn

bony core covered by keratin sheath (AKA bone)

unbranched, permanent with indeterminate growth

projection of frontal bone

found on both sexes, larger on males

horns

central core of hair

medulla

middle layer of hair that surrounds the medulla

cortex

outer layer of hair

cuticle

incisor procumbency where teeth point outward

proodont

incisor procumbency where teeth point straight down

orthodont

incisor procumbency where teeth point backward

opisthodont

place entire foot on the ground (digits to ankle/wrist)

plantigrade

walk only on digits, have elevated the carpals/tarsals off the ground

digitigrade

bearing weight on terminal phalange and specifically on the hooves

unguligrade

3 pricipal cusps arranged in a triangle in the upper tribosphenic molar

trigon

cusp on the lingual side of the tooth in upper teeth

protocone

cusp that is anterior and labial in upper teeth

paracone

cusp that is posterior and labial in upper teeth

metacone

crests that separate cusps from one another

cristae

ledge located along the labial side of the tooth, which may support additional cusps

stylar shelf

molar with 3 cusps

tribosphenic molar

lower teeth version of trigon

trigonid

labial cusp on the lower teeth

protoconid

anterior & lingual cusp on the lower teeth

paraconid

posterior & lingual cusp on the lower teeth

metaconid

4th cusp on posterolingual side of the tooth (upper)

hypocone

cusp that is added when teeth are quadritubercular

hypocone/hypoconid

4th cusp on posterolingual side of the tooth (lower)

hypoconid

crescent shaped ridge formed in selenodonts

selenes

bladelike teeth designed for cutting/slicing ex: carnassials

secodont

PM4m1

carnassial pair