Mammalogy Lab 1: Skull, Teeth, and Terms

Goals of today’s lab

Be able to:

• Locate all structures listed on handout

• Define all terms on handout – what they

are or what they look like

• Give examples of mammals that have, or

lack, the features you are required to learn

Lab Rules

• No food or drinks

• Handle specimens with clean hands

• Please don’t pet the mammal skins

• Skulls are VERY fragile. Careful when opening, or

closing boxes or vials with skulls.

• If you want to point to something on a skull or skin,

use your finger or the point of a folded up paper.

Scientific Nomenclature

Kingdom, Phylum, Class, Order, Family, Genus, Species

• Orders and Families: first letter is always capitalized

– Most Orders in Class Mammalia end in “a”

– Most Families in Class Mammalia end in “idae”

• Specific Epithet:

– Genus (capitalized) followed by species (not capitalized)

– Written in italics OR underlined, but not both

– When keyed only to genus, customary to write the genus

followed by “spp.”

Scientific Nomenclature

• Example: Western spotted skunk

Order: Carnivora

Family: Mephitidae

Genus: Spilogale or Spilogale

Specific epithet: Spilogale gracilis

or

Spilogale gracilis

Grading

• Lab = 50% of your grade!

• Quizzes

– Worth 20 points each

– Lowest quiz dropped

– Beginning of labs, covering material from last lab

• Extra Credit

– Each quiz with 1-2 challenging extra credit questions

– Extra credit only applies to lab grade

Points on Quizzes

For full credit, you will need to:

• Identify specimen correctly

• Follow nomenclature rules (underline, capitals)

• Spell things correctly

Tips

• Look at scientific names for upcoming labs so

you know the Latin names ahead of time

• Use flash cards if they help you

• Work with your classmates

• Memorize as you go

• Make and use keys

Useful Study Guide:

Animal Diversity Website at the

University of Michigan

http://animaldiversity.ummz.umich.edu/site/index.html

• Click on “mammals” tab

http://animaldiversity.ummz.umich.edu/site/accounts/s

pecimens/Canidae.html

• general site for skull structures, using canid skulls

Dental formulae

Dental formulae

2 41

3

Canis lupus = I3 C1 P4 M2

Dental formulae

1

3

Canis lupus = I3 C1 P4 M2

i3 c1 p4 m3

1

4

3

3

Dental formulae

1

3

Canis lupus = 3/3 1/1 4/4 2/3

or

3-1-4-2 / 3-1-4-3

Dentition

Incisors: Usually unicuspid, often for grasping or cutting

• In primitive eutherians, 3 upper incisors per quadrant

• In metatherians, 5 upper incisors per quadrant

• Restricted to premaxilla

Dentition

Canines: Unicuspid and single-rooted, often for holding

and stabbing

• Never more than 1 per side in cranium or mandible

• First teeth in the maxilla

Dentition

Premolars: Unicuspid to multicuspid, vary in size and

function

• In primitive eutherians, 4 per quadrant

• In metatherians, 3 per quadrant

• Deciduous

• Typically with only one row of cusps

Dentition

Molars: Biscuspid or multicuspid, vary in size and function

• In primitive eutherians, 3 per quadrant

• In metatherians, 4 per quadrant

• Fully erupted only in adults

• Typically with more than one row of cusps

Dilambdodont = cusps comprised of “V”s

or “W”s.

Found in bats, shrews, moles.

Bunodont = 3-4 rounded cusps.

Found in pigs, bears, raccoons, humans.

Dilambdodont = cusps comprised of “V”s

or “W”s.

Found in bats, shrews, moles.

Dilambdodont = cusps comprised of “V”s

or “W”s.

Found in bats, shrews, moles.

Bunodont = 3-4 rounded cusps.

Found in pigs, bears, raccoons, humans.

Lophodont = elongated,

transverse cusps.

Found in many rodents.

Dilambdodont = cusps comprised of “V”s

or “W”s.

Found in bats, shrews, moles.

Bunodont = 3-4 rounded cusps.

Found in pigs, bears, raccoons, humans.

Lophodont = elongated,

transverse cusps.

Found in many rodents.

Selenodont = cusps elongated

anterio-posteriorly.

Found in many ungulates.

Characteristics of Mammalian Skulls

Characteristics of Mammalian SkullsOccipital condyles

Characteristics of Mammalian SkullsHeterodont dentition

Characteristics of Mammalian SkullsTemporal fossa

Characteristics of Mammalian SkullsMandibular fossa

Skull Structures to Knowalisphenoid dentary

basioccipital maxilla

basisphenoid nasal

angular process occipital

auditory bulla occipital condyle

coronoid process orbit

cranium palatine

external auditory meatus parietal

foramen magnum postorbital process

frontal premaxilla

incisive foramina presphenoid

infraorbital canal/foramen pterygoid

jugal rostrum

lacrimal sagittal crest

squamosal mandible

temporal ridge zygomatic arch

mandibular condyle zygomatic process

mandibular (glenoid) fossa

Characteristics of mammalian skulls covered in test 1