Mammalogy Lab 1: Skull, Teeth, and Terms

Mammalogy Lab 1: Skull, Teeth, and Terms

Be able to: Goals of today s lab 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 Canis lupus = I3 C1 P4 M2 2 4 1 3

Dental formulae Canis lupus = I3 C1 P4 M2 i3 c1 p4 m3 3 1 4 3 3

Dental formulae Canis lupus = 3/3 1/1 4/4 2/3 or 3-1-4-2 / 3-1-4-3 1 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.

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. 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 Skulls Occipital condyles

Characteristics of Mammalian Skulls Heterodont dentition

Characteristics of Mammalian Skulls Temporal fossa

Characteristics of Mammalian Skulls Mandibular fossa

Skull Structures to Know alisphenoid basioccipital basisphenoid angular process auditory bulla coronoid process cranium external auditory meatus foramen magnum frontal incisive foramina infraorbital canal/foramen jugal lacrimal squamosal temporal ridge mandibular condyle mandibular (glenoid) fossa dentary maxilla nasal occipital occipital condyle orbit palatine parietal postorbital process premaxilla presphenoid pterygoid rostrum sagittal crest mandible zygomatic arch zygomatic process Characteristics of mammalian skulls covered in test 1