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89 Cards in this Set
- Front
- Back
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What are five reasons for studying mammals?
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humans are mammals
applied research (answering a specific question) management of domestic species (product, pet) management of wild population (game, pests, disease vectors, preserving species/ ecosystems) basic research |
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How many species are in each of the 5 vertebrate groups and when did they evolve?
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vertebrates # species MYA
Fish 29000 520 Birds 10000 140 Reptiles 7000 310 amphibians 5700 370 mammals 5500 220 |
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What are the three subclasses of mammalia?
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• Prototheria
Monotremes • Metatheria Marsupials • Eutheria Placentals |
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What is a cladistic tree?
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• Basis of shared derived characters
• Made up of synaptomorphies Example- dentary-squamosal jaw joint |
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What are the mandatory ranks?
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• Kingdom, phylum, class, order, family, genus, species
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What are the mandatory ranks for mammals?
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• Animalia, chordata, Mammalia
29 orders 153 familes 1229 genera 5485 extant species |
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How are species named?
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• Binomial Genus species epithet
italicized or underlined genus capitalized “formal” or “latin name” |
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What are (1) key physiological features of mammals?
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• 1. Endothermy
produce own body heat maintain high body temperatures over a range of different environmental temperatures allows mammals to live in a wide variety of habitats energetically costly • need to eat a lot of food to make up for the cost all following features are related to endothermy |
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What are (7) key features of the skill and mandible of mammals?
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• 1. A single lower jaw bone on each side, the dentary
mandible includes both sides fuse at the rostral end other vertebrates have multiple bones • increases weakness • 2. A dentary-squamosal jaw joint articulates with dentary most globally accepted diagnostic feature of mammals • 3. Three middle ear ossicles: maleus, incus, and stapes ossicles- “little bones” help intensify sound external ear- pina middle ear- ossicles inner ear- coloclea reptiles only the a stapes • mammals can hear 1.5X better • 4. A complete secondary palate separates passage for air and food can eat and breath at the same time • makes eating faster • makes endothermy possible • 5. Heterodont dentition teeth of different size, shape, structure, and function not all mammals have this • dolphins have homodont dentition • ancestors were homodont and first mammals were heterodont • most living mammals are heterodont • 6. Diphyodonty two fold production of teeth (deciduous and adult teeth) • adult teeth are more robust • vs polyphyodonty o teeth are replaced continuously • mammals are diphyodonty because they can’t loose the specific functions • 7. Two occipital condyles articulate with the first vertebrae (axis) gives strength, right range of movement, strong and stable |
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What are (3) key post-cranial features of mammals?
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• Cervicle, thorasic, lumbar, sacral, caudal
• 1. No lumbar ribs restricted to thorasic region • reptiles have lumbar ribs allows mammals to be more mobile • 2. Limb growth away from the joints fuse and disappear other vertebrates grow from each end articular surfaces composed of bones • makes it stronger cartilage replaced by bone in adults • gives stronger/ stable articulation ephyseal plate • between the middle of the bone (diaphysis) and the ends of the bone (epiphysis) • cartilaginous |
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What are (7) key features of soft anatomy of mammals?
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o Features of soft anatomy
• 1. Mammary glands only in mammals developed from milk ridge nonfunctional in males produces milk • 2. Hair at some point all mammals have some hair used for insulation, concealment, communication, sensing immediate surrounding • vibrissae are sensitive to touch o stiff and attached to nerves • 3. Well-developed dermal facial musculature display emotion important for suckling move eyes, ears and whiskers • 4. An enlarged brain lots of variation higher intelligence • 5. A four-chambered heart efficient, oxygenated/deoxygenation blood separated • 6. Enucleated red blood cells no nuclear, increase oxygen carry capacity • 7. A complete muscular diaphragm separates thoracic cavity from abdominal cavity muscular diaphgram pumps air into lungs and improves efficiency |
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What are the (7) parts of the tooth?
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Parts of the tooth
• Crown o Above the gum line • Root o Below the gum line • Alveolus (alveoli = plural) o Boney socket in which tooth sits • Dentine o Bulk of tooth, harder than bone, rough texture • Enamel o Coats dentine, hardest vertebrate tissue, smooth • Cementum o Coats the root, least hard • Pulp cavity (with pulp inside) o Solf, cellular region containing blood, and nerve supply to the tooth o A toot canal close up with the adult teeth are in and stop growing o Rooted teeth • Root canal closes off |
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What are the basic tooth types?
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• Incisors
o Located in the premaxilla o Anterior, simple, chisel-shaped o Grabs, told, tear, gnaw o “caniniform incisors” look like canines but are incisors • Canines o Simple, conical, grabs/holds/pierces o No more than one per quadrant • Premolar • Molar |
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How is height described in teeth?
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• height
o brachydont • low crowned o hypsodont • high crowned • can wear more (horse) |
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what are the (6) different description of teeth?
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• heterodont
o “variable” teeth o most mammals are • homodont o same teeth o secondarily derived in mammals • edentate o no teeth o secondarily derived • diphyodont o two sets of teeth o deciduous • monophyodont o one set of teeth • polyphyodont o continuously replaced o non-mammalian vertebrates |
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what are the terms for orientation on teeth?
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Orientation
• labial o closest to the lips • lingual o closest to the tongue |
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what are the regions and cusps of tribosphenic cheek teeth?
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• Trigon made up of
o Paracone o Metacone o Protocone • Trigon • Cingulum o Selflike ridge runs around the outside of tooth • Parastyle o Most anterior cusp on singulum |
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What are the (6) types of cheek teeth?
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• Dilambdodont
o Occlusal surface forms a W shaped ridge • Zalambodont o Occlusal serface forms a V shaped ridge • Bunodont o Tooth with smooth rounded cusps used for crushing • Selenodont o Major cusps form cresent shaped ridges that are oritented parallel to tooth row o Side to side grinding • Lophodont o Major cusps for long straight ridges (lophs) that are perpendicular to tooth row o Fore to aft grinding o Loxodont • Lophodont with especially high, sharp ridges (elephant) • Carnassial/ secodont o Dentition specialized for meat eating o Carnassial tooth are a pair that act like scissors |
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What are other descriptive terms for cheek teeth?
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• Pectinate
o Resembles a comb in structure (ring tailed lemur) • Quadrate o Square tooth • Hypocone o New cone assed in quadrates • Tusks o Elongated teeth that protrude from the mouth o Ever growing o Not checked by opposing teeth |
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Why are teeth so diverse?
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• To maintain endothermy
o Need to obtain and process food • Teeth can tell us diet, homerange, age |
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How do incisors differ between different mammals?
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• Rodents have a single pair, evergrowing (rootless) self sharpening
• Orange/yellow enamal surface • Worn down by rubbing together, which gives a beveled shape • Vampire bat has sharp incisors • Shrews have bilobed with iron containing pigmented enamel • Fossorial rodents may use their incisors to dig |
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How do premolars and molars differ?
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• Grouped together as “cheek teeth”
• Premolars are usually simpler • Incisors, canines, premolars all usually have deciduous precursors • Molars never have decisuous precursors |
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what is the primitive condition for teeth?
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• Tribosphenic cheek teeth
all other teeth are derived |
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What are the stem amniotes?
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340 MYA during the carboniferous period
• Earliest members of group of vertebrates including birds, dinosaurs, mammals • Lizard-like, insectivore/herbivores • Small but up to 2 meters • Notable for their eggs |
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What are characteristics of an amniotic egg?
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o Adapted to survive away from water
o Amniotic egg • Shell • 4 membranes- thin layer of tissue yolk sac • surrounds yolk, supplies nutrients to the developing embryo chorion • outer membrane, protects the egg allantosis • collects waste products from embryos amnion • immediately surrounds and protexts the embryo • all organisms with amniotic eggs belong to Amniota a synaptomorphy for amniotes |
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What are anapsids?
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Anapsids “without arches”
• Caudal to eye, no open part of bone- temporal region • Turtles o Jaw muscles are inside bony skull o Limits size and abaility to bulge |
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What are diapsids?
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Diapsids “double arch”
• Two openings in temportal bone • Greater development of the jaw muscles and lighter skull |
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What are synapsids?
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Synapsids “fused arch”
• Greater development of the jaw muscles and lighter skull • Only surviving synapsides are mammals |
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What are characteristics of pelycosaurs?
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• Dominant tetrapods in early Perminan
• Roughly 70% of tetrapod genera • Morphologically diverse o Amphibious/ terrestrial o Large >10fts o Preyed on small diapsid/anapsid o Sprawling gate, ribs along most of body • Tanklike, but little flexibility |
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What is a dimetrodon?
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type of pelycosaur
o Dimetrodon • 10 ft long, carnivorous • sail like flap of skin, supported by vertebral spine • ectothermic used spine to warm • “barely heterodont” • no secondary palate air comes directly into mouth |
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What are characteristics of therapsids?
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• “Mammal-like reptiles”
• Not a reptile though • Dominated throughout late Permian • Morphologically diverse o Include herbivores/carnivores • Smaller than pelycosaurs o Modern weasel • Legs under body more (more agile) • Heterodont- more differentiated o Incisors, canines, cheek teeth |
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What are characteristics of cynodonts?
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• Mammals evolved from these late therapsides
• Lok more mammal like • Stance more upright • Ribs lost from lumbar region • Cheek teeth with recognizable cusp; wear pattern not regular • Partial secondary palate o Important for endotherms • A dentary-squamosal jaw joint o The most globally accepted diagnostic feature of mammals • Therapsids declined at mass extinction at 248 mya o Cynodonts survive into Triassic, but affected by dinosaurs o Survived cynodonts were small, inconspicuous, nocturnal • Gave rise to mammals |
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What are characteristics of morganncodontids?
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220 mya- MAMMALS
• morganncodontids o well represented o small, <6 in, shrew-like o stance upright o agile skeleton o precise occlusion of cheek teeth, diphyodont o insectivores, secondary palate complete o good hearing, sense of smell, hair, endotherms |
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What are characteristics of multiteburculates?
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"rodents of Mesozoic"
o extremel successful, numerous, widespread, around for >100 my o mouse-squirrel like, large front incisors followed by diastima o cheek teeth with many cusps (tubercles) o teeth good for grinding plants o extinct into cenozoic • probably competition with rodents |
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What were characteristics of Mesozoic mammals?
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o Can weigh 30 lbs (dog size)
o Another rat size had small dinosaurs in gut o Could be specialized • Gliding, amphibious, mole-like |
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What changes in morphology were unique to mammals?
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• Skeleton
o Increasing flexibility, loss of ribs, lighter skeleton, less rigid • Dentition o Increasing dental complexity, more efficient calorie extraction, wider range of diet o Changes in the lower jaw • Dentary bone gets larger to being only bone Increasing jaw strenth, more calorie extraction wide range of diet • Changes in jaw joint and middle ear o Quadrate and articular shrink from jaw joint to the middle ear incus, maleus in mammals o Angular shrinks (eardrum piece) into the tympanic (hold the ear drum) o Pick up vibrations • Send to middle ear o Dramatic changes in flora, fauna • Meteor in Yucatan, killed dinosaurs, large mammals Allows for mammal diversification and undergo massive radiation Flowering plants, take off • Seeds, flower, nectar, insects |
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When did monotremes diverge?
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• Monotremes diverged first about 180 MYA
o Pangea was still present • Laurasia was the northern part • Gondwana was the southern part o Poor fossil record • There probably never were many • First fossils were found in Australia and the southern part of South America • There are probably fossils in Antartica • Today Australia, New Guinea, and Tasmania are the only places to have monotremes o Five living representatives • Platypus, short-beaked and 3 long-beaked echidna |
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What are primitive characters of the subclass prototheria?
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o Primitive characters
• Lay soft-shelled eggs • Extra bones in the shoulder girdle Epicoracoid Coracoid Interclavicle Fused clavicle • Extra bones in pelvic girdle Epipublic bones • Cervival ribs • Reptilian posture |
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What are synapomorphies of the subclass prototheria?
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• No teeth in adults (edentate)
Platypus have infant cheek teeth • Have keratin ridges to grind Echidnas have keratin on tongue and roof of mouth • Delicate skull • Ankle spur in males only Linked to vemon gland via venom duct Gland not functional in echidnas |
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What are characteristics of the platypus?
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• 1-1.5 meters long
• amphibious streamlined body, dense fur, webbed feet, flattened tail • duck-bill soft, pliable, sensitive to touch • can catch half of its body mass in invertebrates with eyes and nose shut bill is covered with eletroreceptors • builds burron in the bank above water level • large foreclaws with webbed feet, which it folds back to dig |
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What are characteristics of echidnas?
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• Five species
• Common: short billed echidnas • Spines Density varies in species Digging morphologies • Well developed forelimbs/ claws • Long, slender snout • Tongue is thin, narrow, shoots out Eat ants, termites, etc • Can live up to 50 years |
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What are synapomorphies of the subclass metatheria?
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• Viviparity
Livebearing • Loss of shoulder bone Lighter, more flexible skeleton • Loss of cervical ribs Improve flexibility • Upright posture • Tribosphenic dentition |
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How did members of the metatheria subclass originate? What is their history?
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o Diverged 140 MYA
o Make up 5% of the extant mammals o First found/ originated in Asia • Sinodelphys Oldest known marsupial Adapted for arboreal lifestyle Insectivore • Late Mesozoic Found in Europe, Africa/north America, south America, antartica (43% of mammals) • Early Cenozoic Only found in south America and Australia (3%) Placental mammals probably took over • South America had large herbivore placentals • Large carnivourous marsupials • Great American interchange (2.5 MYA) North south America came back together and the marsupials went to north America • Opossom was the only one to persist |
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what is the distribution of extant marsupials?
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• North America (1 species)
• South America (93 species) • Australia and surrounding islands (237 species) |
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What are synapomorphies of extant marsupials?
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• Unique mode of reproduction
• Inflected angualar • Angular process of dentary dents in |
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What are the (7) orders of the subclass metatheria?
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Didelphimorphia
Paucituberculata Microbiotheria Dasyuromorphia Peramelemorphia Notoryctemopha Diprotodontia |
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What are characteristics of Didelphimorphia?
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• Largest by far
• Most primitive • Would be basis of phylogeny • Generalized body plan |
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What are characteristics of Paucituberculata?
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Panciturberculatia “shrew opossum”
• Small order with 6 species • • eat insects • diprotodont dentition o botton incisor juts out to meet top incisors o lower jawbone shorted • first incisor elongated |
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What are characteristics of Microbiotheria?
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Microbiotheria
• “monito del monte” • one species • pointy mouth • unique skull • special link between south America and Australian mammals |
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What are characteristics of Dasyuromorphia?
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• Large, diverse order
• Basal stock for Australian radiation • Most are meat eaters • Tasmanian wold o Extinct in 1936 |
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What are characteristics of Peramelemorphia?
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• Bandicoots and
o 21 species of bandicoots o long pointed snout, compact body o hind limbs modified for hopping • forth toe enlarged, 2nd/3rd fused syndactyly (fused toes or fingers) |
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What are characteristics of Notoryctemorphia?
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• Marsupials and moles
• 2 extant species o fossorial • compact body, dense fur, enlarged front claws, vestigial eyes o foreclaws used to swim through sand o snout with a horny shield |
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What are characteristics of diprotodontia?
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• Wombat, possum, sugarglider, marsupials
• Largest order with 143 species • Both are present o Diprotodont dentition o Syndactyly • Half of order is the kangaroo and wallaby o 65 species • the most derived marsupial • fine tuned vegetarians • marsupial version of ungulates |
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What are synapomorphies for the subclass eutheria?
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o Loss of primitive characters
• Loss of epipublic bones • Unique mode of reproduction Eutherians have much more developed new borns at birth • Large brain size relative to body size • High metabolic rate About 30% higher than the other two groups • Able to be more active o Addition of new characters |
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When was the origin of eutherian mammals? And what were the first fossils found?
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o 140 MYA
o ealiest fossil eutherian mammal • Eomaia Dawn mother Found in Asian suggesting an area or origin Small in body size Skeleton suggest it was arboreal • Long fingers and toes o 65 MYA (Cenozoic Mesozoic) • eutherians start to diversify like crazy and increase in number • orders begin to become recognizable • greatest adaptive radiation ever seen |
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What are characteristics for Rodentia?
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• Order Rodentia
o Rats, mice, allies o Largest mammalian order o More than 2000 species o A single pair of ever-growing, self-sharpening incisors • Enamel on the outside and dentine on the inside o Small in body size o Reproduce rapidly |
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What are characteristics for Chiroptera?
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• Order Chiroptera
o Bats o Only Volant mammals • Body plan highly modified for flying o Microbats • Small body size • Eat insects • Use echolocation to navigate and locate prey Small eyes, elaborate ears, projections around the nose and mouth • 80% of extant bat species o Megabats • Large in body size • Eat fruit, pollen, nectar • Visually oriented (large eyes) • “flying foxes” |
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What are characteristics for Soricomorpha?
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o Shrews, moles, selenodons, and allies
o More than 400 species • 300 are shrews o small body size o relatively small brain o poor eyesight o teeth well designed for eating insects • sharp teeth for crushing insects • dilambidonts and zalambdodont |
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What are characteristics for Primates?
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o Moneys, apes, humans, allies
o “First Animal” o Most species are arboreal • Excellent vision Because of 3D environment • Relatively large brain Complex environment • Ability to grasp with hands and/or feet |
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What are characteristics for Carnivores?
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o Meat eaters
• Well developed canines • Recognizable carnassial pair o Includes seals, sea lions, and walruses • Decended from terrestrial carnivores |
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What are characteristics for Artiodactyla?
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o Antelope, deer, pigs, hippos, and allies
o Diverse and successful o “even-toed ungulates” • weight passes between the 3rd and 4th toes • “cloven hoof” o most are plant eaters • large cheekteeth with complex surfaces • selenodont • multichambered stomach allows them to retain more nutrition from plant material |
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What are characteristics for Lagomorphia?
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o Rabites, hares, pikas
• Closest living relatives to rodents o Tiny second upper incisors behind the first • No rodents have that |
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What are characteristics for Cetacea?
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o Whales, dolphins, porpoises
o Fully aquatic o Evolved from terrestrial mammals o Suborders • Baleen whales Large in body size Filter feeders; baleen replaces teeth • Toothed whales Usually smaller than baleen whales Have teeth More species than baleen whales Dolphins, porpoises o Closest living relative hippo • Order artiodactyla |
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What are characteristics for Afrosoricida?
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• Order Afrosoricida
o Tenrecs, golden moles, otter shrews o Zalambdodont dentition |
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What are characteristics for Erinaceomorpha?
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o Hedgehogs and gymnures
o Highly varied diet • Cheekteeh bunodont: smooth rounded cusps o Quadrate |
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What are characteristics for Cingulata?
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o Armadillos
o Bony scutes covered with a thin layer of keratin o Powerful forelimbs o Distinctive teeth • Homodont dentition |
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What are characteristics for Scandentia?
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o Tree shrews
• Look like squirrel with pointed nose o Large, prominent eyes o Relatively large brain o Close relatives to primates |
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What are characteristics for Perissodactyla?
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o Horses, sebras, tapirs, rhinos
o Odd-toed ungulates o Weight passes through the 3rd middle toe o Once a very large order, but now it includes fewer than 20 species |
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What are characteristics for Macroscelidea?
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o Elephant shrews
• Long, flexible snout • Superficial resemblance to shrews • Hind limbs adapted for leaping o “large hind limb” |
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What are characteristics for Pilosa?
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o Anteaters
• Specialize in eating ants and termintes Giant claws on the forefeet Long skull No teeth o Slothes • Feed on leaves • Large claws on all four feet • Very long forelimbs • Skull short and blocky |
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What are characteristics for Pholidonta?
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o Pangolins
o Eat mostly ants o Covered with keratin scales o Large claws on the fore feet o No teeth |
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What are characteristics for Subungulates?
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o Sirenia, Hyracoidea, Proboscidea
o Originated in Africa from Ungulate stock o Sirenia • Manatees and dugongs • Zar skulls • Fully aquatic • Plant eaters o Hyraacoidea • Hyraxes Prominent gap between front incisors Rubbery pads on bottom of feet • Sweat and act as suction cups o Proboscidea • Elephants • Largest terrestrial mammals • 3 species 2 in Africa and 1 in asia |
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What are characteristics for Dermoptera?
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o Flying lemurs
o Accomplished gliders • Back has silky fur o Lower incisors are pectinate • Each tooth lookes like a comb o Prominate eyes, relatively large brain • Like primates and three shrews (three are historically related) o Closely related to primates with tree shrews being the next closest |
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What are characteristics for Tubulidentata?
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o Aardvark
• “earth pig” o Long, pig-like snout o Large, powerful forelimbs/ claws |
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What was the feeding structure of the first mammals?
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• First mammals were insectivores- primitive condition
o Gave rise to carnivores, herbivores, specialist (feeds on a limits number or things) |
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What are characteristics of insectivores?
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o Species that feed on a variety of small invertebrates
• Adult insects, insect larvae, worms, etc o Widespread in mammals • Has been retained in a lot of modern orders o Most do not have special adaptations for capturing insects • Just go out and grab them and eat them o Most have a generalized body plan • Microbats are the exception Most are insect eaters and are the most effective insect catchers o Teeth are usually specialized for eating insects • Dilambdodont • Zalambdodont o Skull and jaw morphology • Simple • Unspecialized • General hinge motion o Digestive tract • Simple, unspecialized |
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What are characteristics of specialized insectivores?
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• Specialized insectivores
o About 20 species that eat colonial insects (ants and termites) • Myrmecophage Species that specializes on eating ants and termites Echidnas, numbat, anteater, aardwark, anteaters, pangolins, aardwolf Has evolved independently several times o Most have spines, scales, or very thick hair or skin • Protect them from ant and termite bites • Except aardwolf Lick them up with a big sticky tongue and then leave before worker insects come in and attack o Most have strong forelimbs and claws • Designs for ripping apart nests o Well-developed sense of smell o Elongated skulls o Teeth are reduced or absent o Tongue is extremely long and circular in cross section • Allows it to probe into nest • In anteaters the tongue originates on the sternum and the salivary glands are huge o Sticky saliva o Great case of convergence |
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What are characteristics of Carnivores in terms of feeding?
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• Carnivores
o Species that feeds largely or entirely on meat o Meat specialist o Most are members of the Order Carnivora and many others as well o Obtaining food can be dangerous and injuries are common |
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What are feeding characteristics of cats?
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• Agility, speed, endurance
• Acute sense of smell and hearing • Eyes face forward, which gives good depth perception The eyes give overlapping views, which the brain can determine depth from • Long sharp claws • Longue covered with backward facing hooks Toughened by keratin Used for scraping meat from a carcus and holding struggling prey • Teeth are distinctive Prominent canines for holding on and catching prey Well developed carnassial pair Reduced dentition because they swallow • a strong skull and jaw uppers and lowers come together like scissors temporalis muscle • in the temple region • responsible for having a strong bite sagittal crest well developed corocoid process which attaches to the temporalis muscle small masseter • responsible for fore/aft and side to side motion • Digestive tract Short and simple Larger stomach to gorge themselves Cecum • Saclike cavity within which bacteria break down plant material |
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What are characteristics of gnawing herbivores?
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• Most belong to Order Rodentia or Order Lagomorpha
• Huge, ever-growing, front incisors followed by a diastema (rabbits have a second row of first incisors • Lips can be folded behind the incisors • The cheeckteeth are homodont • Lophodont or prismatic • Hypsodont (high crowned) or evergrowing To make teeth last longer Fore to aft grinding • All lagomorphs are herbivores, but not all rodents are herbivores |
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What are characteristics of grazing and browsing herbivores?
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o Grazing and browsing herbivores
• Order Artiodactyla, Perisoodactyla and others • Grazers Eat primarily grass • Browsers Eat young leaves, flowers, and fruits • Cheeckteeth are well developed for plant eating Homodont Lophodont or selenodont Hypsodont or ever-growing Side to side jaw motion • Ridges on teeth are parallel to tooth row • Jaws are very different than carnivores Masseter muscle is well developed • Used in side to side and fore aft movement • Masseteric fossa large Temporalis muscle small • Coronoid process is small Jaw articulation well above toothrow • In carnivores the jaw articulation even in toothrow o Stronger, scissorlike • Flexible, allows chewing |
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What is the digestive tract of herbivores like?
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Longer, more complex
Cellulose needs to be broken down by microorganisms in the digestive tract • Fermentation o The breakdown of cellulose by microorganisms o Hind gut fermentation • Rabbits, rodents, horses • Fermentation occurs in the cesum and the colon • Fast, not very efficient • Poor quality food is eaten in abundance o Foregut fermentation • Artiodactyls • Fementation starts early in the stomach region (usually multichambered) Mixes food with microorganisms early • Large cecum • Slow, highly efficient • Eats high quality food, but can live where it is less abundant |
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What are characteristics of omnivores?
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o Species that feed on a variety of food type
o Hard to characterize o Have all 4 tooth types o Brachydont o Usually bunodont • All purpose dention |
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What are characteristics of mollusk specialists?
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• Sea otter, walrus
• Robust teeth because they need to chew shells sometimes Strong, broad, flat |
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What are characteristics of filter feeders?
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• Baleen whales, crab eating seal
• Takes in large amounts of water and then filtering • Sieve teeth, baleen use to filter |
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What are characteristics of piscivores?
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• Fish eaters
Toothwhales, seals, sea lios Alongated jaw ans lots of teeth Homodont or close to homodont dentition • Had heterodont dention Good for slippery fish |
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what are characteristics of nectarivores?
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• Nectar eaters
• Humming birds of mammal world • Important pollinators Bats, honey possom, • Evolved at least 3 times independently • Snouts are elongated • Teeth are reduced or absent • Long slender tongue with a brush at the tip |
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what are characteristics of frugnivores?
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• Fruit eaters
Most megabats Put in mouth and get juice out • Teeth are distinctive Large with flat basins Height of crawn reflect toughness of fruit |
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What are characteristics of sanguinvores?
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• Blood eaters
Scalpel-like incisors • Scrap away from the skin until It begins to bleed Grooved tongue Saliva with an anticoagulant |
