Module 10: Species Identification-Mammals Flashcards

Question

Species determination cont.

Answer 1

Some features quickly rule in/out classes Mammals-sculpted elements Amphibians/reptiles-rounded/smooth elements Birds-angular at some ends Fish-pointy Birds-lighter bones, thinner cortex (and amphibians) Mammals-thick cortex Reptiles-between Fish bones-shiny, semi-translucent, mammals not; fish bones flat

Answer 2

Consistent, some species very close in appearance Step 1: what bones, cranial/post?, dental/long bone? Can rule out some classes/orders Step 2: development and size Step 3: eliminate orders/families based on form Step 4: species elimination based on subtle variations-comparative analysis, may not be poss if no distinguishing features Variation due to age/sex influence appearance & individual variation Variation w/in species

Answer 3

Genus and species: goal Family next most desirable Final reports indicate if you are ID’ing element/skeleton to class, order, family, genus, species

Answer 4

Once in genus, evaluate key features that distinguish species-important in court cases!

Answer 5

Most diagnostic of species/breed Overall shape suggests group -short/squat, boxy/elongated, low profile/tall profile, etc. size/shape of rostrum and nasal ones, orientation/projections of eyes, size/shape of external auditory meatus and bullae-importance of sense of smell, sight, hearing Size/shape of mandible, dentition-diet Horns/antlers-fighting/protection, location and growth direction characteristic Subtle features-size/shape of infraorbital foramen, termination of palatine, relationship of pterygoid, size, shape, location of incisive foramen, frontal breadth vs postorbital constriction, presense of fenestra, relationship of bones, shape of temporal ridges, size of occipital ridge/shield Provides most info on class, family, genus, species

Answer 6

Scapula-shape distinguishing, shape of glenoid fossa-amnt of rotation allowed, distinctiveness of coracoid from glenoid, acromion process shape, scap spine loc., spine to glenoid fossa, neck appearance Humerus-straightness/curve of shaft, deltoid tuberosity, head shape, size relating to rad/ulna, greater tubercle to head, shape of trochlea/epicondyles, presence of entepicondylar or supratrochlear foramen, size and shape Rad/ulna-fused/unfused, absent/vestigial, size relating to humerus, straight/curvy, shape of articular surfaces Vertebra-shape of centra, number Ribs-flat/round, shape of head and neck, number Os coxa-shape of ilium, ischium, pubis, sizes in relation, fused at pubis or to sacrum, acetabulum shape Femur-length relating to tib/fib, straight/curvy, location and size of 3rd trochanter, shape of head and neck, size of greater trochanter and relationship to head and neck, med/lat condyle variations, patellar surface Tib/fib-fused/unfused, absent/vestigial, size relating to femur, shape of articular surfaces Metacarpals, metatarsals, phalanges-# and length, claws or hooves -plantigrade (sole on ground)- full complement of toes, MC/MT shorter rekating to rad/ulna/tib/fib -digitigrade (toe-walkers)-full complement of toes or slight reduction, MC/MT increased length -unguligrade (hoof-walkers)-reduced toes, MC/MT peak length

Answer 7

Skull-low/flat, orbits indistinct Mandible-well-developed angular process, teeth sharp/pointy, all tooth classes (I:C:P:M) look similar Scapula-blade-like Humerus-lacks neck, greater tubercle above level of head, red/ulna separate, tib/fib fuse at mid-shaft

Answer 8

Skull-low, orbits somewhat distinct, large infraorbital foramen Mandible-coronoid reduced/absent, gonial well-developed, dentition reduced, canines absent, incisors large and chisel-like Scapula-long acromion, late metaacromial process, little/no coracoid Os coxa-long and slender, rod-like ilium, long pubis Forelimb/hindlimb variable, humerus-supratrochlear perforation, no entepicondylar foramen, femur-small head, distinct neck

Answer 9

Similar to humans with mod of forelimb and less mod of hindlimb Look human with more projection of rostral region. All 4 tooth classes, similar to humans, > canines 2 dental formulas: -2/2:1/1:3/3:3/3 (new world monkeys) -2/2:1/1:2/2:3/3 (old world monkeys, apes, humans)

Answer 10

Larger brain, rostral region reduced, zygomatic arches wide, temporal ridges, sagittal crest, occipital crest well-developed (large jaw muscles), large auditory bulla, dentition reduced, enlarged canines Scapula-equal halves by spine, acromion large, some species evidence metacromial process, coracoid small Humerus & rad/ulna-similar in length, humeral head hemispherical, tuberosities above head, cats entepicondular foramen, dogs supratrochlear perforation, bears neither Os coxa-long, narrow, prominent ischial tuberosities Femur-slender, straight in digitgrades, short, stout in plantigrades, length relative to tib/fib similar, greater trochanter rarely rises above head (does in some cats)

Answer 11

Similar in form/function, some distinctions Many distinctions debated

Answer 12

Length of canines in relation to mandibular mental foramina informative -maxilla and mandible in occlusion, draw line across front of mandible through mental foramen -canines below-coyote, dog rarely reaches line, wolf close to line Length from anterior of 1st premolar to posterior of last molar of maxilla to palate width b/w 1st premolars informative: length >=3.1x, coyote, <=2.7x width of palate, dog Reciprocal index-divide palate width by tooth row x 100-coyotes <33, dogs >36, wolf ~34.6 (useful for distinguishing some domestic dog breeds) Coyote-posterior edge of palate terminate b/w anterior edge and midpoint of last molar, in wolf palate termination aligns with posterior edge last molar, extends beyond molar in dogs

Answer 13

Interorbital region of dogs elongated relative to wolves-ration of distance b/w end of tooth row and anterior of auditory bulla to length of tooth row x100 >dogs (64-80) than wolves (59-62)

Answer 14

Orbital angle-angle b/w. Frontal bone and frontal process>zygomatic arch -40-45 degrees=gray wolf -53-60 degrees=dog -between=wolf hybrid

Answer 15

Coyote and fox similar in size, fox have pit at base of postorbital process, coyote, dog, wolf do not

Answer 16

Red vs gray similar, but distinguishable Temporal ridges into V-shape at sagittal suture in red fox, separate and almost U-shaped in gray fox Gray fox has distinct “step” in mandibular ramus anterior to gonial angle or angular process on mandible, red fox lacks “step.”

Answer 17

P4-molar in appearance (squared) raccoons, elongated in dogs-carnassial Raccoon 2 lower molars, dog 3 Palatine further caudally raccoon almost to pterygoid, terminates closer to molars dog Scap notch more pronounced raccoon, supraspinous fossa larger/D-shaped, metacromial process more developed Raccoon noticeable lateral epicondylar flare & entepicondylar foramen Hindlimb more developed on dog than raccoon

Answer 18

Subtle differences Florida panther subspecies maybe distinguishable from others (more arched nasal margin) Bobcat skull rounder from superior view, panther & lion elongated in parietal region Temporal lines stay separate-U shape in bobcat, intersect-V shape and sagittal crest in panther/mtn lion Posterior palatine margin curved-mtn lion, dips anteriorly at midline. Curved w no dip-panther, bobcat-squared

Answer 19

Significantly smaller than bobcat, panther, mtn lion Less dev temporal ridges, more divergent Posterior palatine arched like panther, dips caudally at midline

Answer 20

Last upper molar: grizzly-1.5x+ length of 1st upper molar, black-no more than 1.5x Black bear-more concave face, grizzly-more convex Grizzly-accessory cusps on P4 Grizzly femur has neck as wide as/wider than head, slight intertrochanteric ridge, significantly broader lateral condyle than medial; black bear femur has constricted neck, well dev intertrochanteric ridge, and similarly sized medial/lateral condyles

Answer 21

Horse Pre-molars & molars hypsodont, high-crowned w deeply folded enamel, folds filled w cement Scapula long/narrow, unevenly divided by spine with supraspinous area 1/3 and infraspinous 2/3. Spine ends at middle of neck approx. acromion process rudimentary, coracoid prominent Ilia long and broad, taper to neck superior to acetabulum, opening on acetabulum wide; ischium and pubis short, obturator foramen circular Humerus short in comp to rad/ulna, heavily build, well-dev deltoid tuberosity. Ulna is sig reduced, often fused to rad Femur short w low, broad head. Very large trochanter. 3rd trochanter present. Fibula reduced to splint, may be fused to tibia

Answer 22

Orbits completely enclosed, directed laterally Molar form can be informative: pig-bunodont dentition, round/conical cusps; deer-selenodont, crescent pattern on worn tooth; bovine-hypsodont Ribs flat Scapular spine ends before glenoid fossa, typically before neck Pigs lack acromion process, slight in other species Pig-distinct caudal overhang of spine Coracoid slight swelling in pigs, slight hook others Ilia shorter, neck thicker above acetabulum, acet. Opening narrower, 2 overhanging lips, except pig. Notable supraacetabular fossa on lat of ilium except pig Pubis long, ischium long and wide, oval obturator foramen Humerus short, lightly built w less dev deltoid tuberosity Full ulna, can fuse to rad Pig v tightly aligned rad/ulna w no gap, other species have notch/gap b/w upper aspects of rad/ulna Femur and tibia more similar in length than forelimb Femoral head extends onto neck (not pigs) Greater trochanter above head (not pigs) Bovine, deer and goat, head & neck right angle to greater trochanter, sheep > Pig large/distinct fibula, others absent, vestigial, or fused

Answer 23

Most are Sus scrofa, subtle diffs. Domestic pigs, smaller canines Wild pigs, longer more slender limbs, domestic more curvy/twisty

Answer 24

Sus cristatus-Asiatic/Indian Wild boar Best distinguished by lower canins S. Scrofa, tooth triangular with bead at buccodistal angle, sides flat/concave. S. Cristatus more rounded with sides convex, no bead Pecari distinguished by upper canines-pigs curve out then up, pecari only down

Answer 25

Cervical vertebra strongly opisthocoelous (concave bacl, convex/flat anterior) in sheep, slightly so in pig Humerus, rad, ulna shorter and more S-shaped in pig, particularly domestic pig

Answer 26

Longest/lightest built Antlers that shed each year arising from pedicles on frontal bone. Antler itself is burr/coronet, main stem of antler is beam off which tines/points arise -1st tine is brow, 2nd bez-tine, 3rd trez-tine, after that # points present 1st year antler consists of single prong, after that new tine each year, age est. by # of tines Features of antlers distinct and used for ID Large lachrymal fossa b/w frontal, nasal, lachrymal and maxillary bones. Size/shape of this fossa can help distinguish b/w deer

Answer 27

VERY difficult, maybe not possible Cranial sutures help: coronal suture bows forward at bregma in sheep, nearly straight across in goat, lamboidal suture straight in sheep, bows rostrally in goat Sheep have lachrymal fossa, goats do not Sheep-premaxilla wedged b/w nasal and maxilla, goats premaxilla only touches nasal bone Sheep horn-cores more circular, goats triangular, goats V/U shaped pit on frontal b/w horn-cores

Answer 28

Bovine-horns perm and hollow, supported by horn-cores on frontal bone. Parietals are often reduced in size/nearly absent Cow horns arch forward, bison horns go backward Cow-nasal and premaxilla touch Scapula-glenoid fossa more oval in cow, kidney in bison; coracoid process blunt and distinct from lip of glenoid, arises closer to lip of glenoid and can be hooked in appearance

Module 10: Species Identification-Mammals Flashcards

(52 cards)