Class Mammalia Add to online Mammal lecture Reference back to A&P notes beginning of semester

Prototheria - Monotremes 3 extant genera 3 extant genera all live in the Australia-New Zealand region: all live in the Australia-New Zealand region: Duck-billed platypus (Ornithorhynchus) Duck-billed platypus (Ornithorhynchus) Echidna (Tachyglossus) Echidna (Tachyglossus) Long-beaked echidna or spiny anteater (Zaglossus ) Long-beaked echidna or spiny anteater (Zaglossus ) not considered ancestral to therians not considered ancestral to therians specialized surviving sidebranch specialized surviving sidebranch

Monotremes lay leathery eggs (1 or 2) in underground nests lay leathery eggs (1 or 2) in underground nests cloaca cloaca toothless as adults toothless as adults skeletal differences skeletal differences have cervical ribs have cervical ribs "reptilian" pelvic girdle "reptilian" pelvic girdle lack a bony housing for the ear lack a bony housing for the ear

Monotremes young born very altrical young born very altrical Parental care Parental care platypus - young get milk by sucking/licking the belly hair platypus - young get milk by sucking/licking the belly hair echidna – ventral pouch for incubating and 2 suckling regions. echidna – ventral pouch for incubating and 2 suckling regions.

Subclass Theria Infraclass Metatheria Old system - Order Marsupialia Old system - Order Marsupialia Current – several orders Current – several orders

Subclass Theria Infraclass Metatheria Numerous during Cretaceous (end of Mesozoic) Numerous during Cretaceous (end of Mesozoic) Southern land masses were united Southern land masses were united During Cenozoic During Cenozoic southern masses split, joined northern southern masses split, joined northern Couldn’t compete with placentals. Couldn’t compete with placentals.

Subclass Theria Infraclass Metatheria young born tiny, very immature (altricial) young born tiny, very immature (altricial) gestation short gestation short time in marsupium > uterus time in marsupium > uterus

Subclass Theria Infraclass Metatheria Skeletal differences from eutherians Skeletal differences from eutherians shape of nasal bone shape of nasal bone ancestral dental formulas ancestral dental formulas presence of epipubic bones presence of epipubic bones poor thermoregulators poor thermoregulators

Subclass Theria Infraclass Eutheria Known from late Cretaceous Known from late Cretaceous 18 extant orders 18 extant orders

Order Xenarthra (Edentata) most primitive most primitive sloths, anteaters and armadillos (protective armor) sloths, anteaters and armadillos (protective armor) Strong claws Strong claws adults few to 0 teeth (molars lack enamel) adults few to 0 teeth (molars lack enamel)

Order Pholidota pangolins or scaly anteaters; 7 species pangolins or scaly anteaters; 7 species tropical Africa/Asia tropical Africa/Asia Scaly, epidermal layer Scaly, epidermal layer curl up for protection curl up for protection

Order Pholidota pangolins or scaly anteaters; 7 species pangolins or scaly anteaters; 7 species tropical Africa/Asia tropical Africa/Asia Scaly, epidermal layer Scaly, epidermal layer curl up for protection curl up for protection eats ants and termites eats ants and termites Long tongue, strong digging feet Long tongue, strong digging feet lack teeth lack teeth

“Edentata clade” Order Xenarthra (Edentata) Order Xenarthra (Edentata) Armadillo and anteater Armadillo and anteater Order Pholidota – spiny anteater Order Pholidota – spiny anteater Similarities considered convergent evolution Similarities considered convergent evolution

Stand alone groups Insectivora Insectivora Carnivora Carnivora

Primates hands that grasp hands that grasp often opposable thumb (pollex) or big toe (hallux): often opposable thumb (pollex) or big toe (hallux): well-developed sense of touch well-developed sense of touch Most have flat finger/toenails Most have flat finger/toenails

Primates Enlarged brain Enlarged brain Stereoscopic color-vision Stereoscopic color-vision Many omnivorous Many omnivorous Most are social Most are social

Primates 2 subdivisions 2 subdivisions

Primates prosimians or lower primates prosimians or lower primates prosimians mostly small, nocturnal mostly small, nocturnal Most rely on smell more than sight or sound Most rely on smell more than sight or sound Lemurs, tarsiers …. Lemurs, tarsiers …. Lemurstarsiers Lemurstarsiers

Primates The Anthropoids or higher primates The Anthropoids or higher primatesAnthropoids Most larger, diurnal. Most larger, diurnal. Apes Apes no tails no tails Larger brain Larger brain Larger body Larger body More upright More upright Fewer offspring, slower to mature Fewer offspring, slower to mature Sight more than smell Sight more than smell Monkeys Monkeys nearly all have tails nearly all have tails

Primates New World: all monkeys. New World: all monkeys. Fairly small and exclusively tree dwelling. Fairly small and exclusively tree dwelling. Marmosets and tamarins, Marmosets and tamarins, Marmosets and tamarins Marmosets and tamarins squirrel, spider, woolly, and howler monkeys, squirrel, spider, woolly, and howler monkeys, Old World: comprise monkeys, apes and humans. Old World: comprise monkeys, apes and humans. Bigger and spend more time on the ground. Bigger and spend more time on the ground. Macaques, Baboons, Mandrills and Drills, Geladas, Mangabeys, Guenons, Leaf-eating monkeys (Langurs, leaf monkeys, colobus, proboscis) (Cercopithecidae) Macaques, Baboons, Mandrills and Drills, Geladas, Mangabeys, Guenons, Leaf-eating monkeys (Langurs, leaf monkeys, colobus, proboscis) (Cercopithecidae) MacaquesBaboonsMandrills and DrillsGeladas MangabeysGuenonsLeaf-eating monkeys MacaquesBaboonsMandrills and DrillsGeladas MangabeysGuenonsLeaf-eating monkeys

Primates apes: apes: Hominidae: Hominidae: gorillas gorillas gorillas chimpanzees and bonobos (aka pygmy chimps), chimpanzees and bonobos (aka pygmy chimps), chimpanzees and bonobos chimpanzees and bonobos Humans Humans Pongidae: orangutan Pongidae: orangutanorangutan Hylobatidae: gibbons and siamang Hylobatidae: gibbons and siamang

Chiroptera Bats – only flying mammal Bats – only flying mammal Wings – membrane between fingers Wings – membrane between fingers Different from birds and pterosaurs Different from birds and pterosaurs

Chiroptera Bats – only flying mammal Bats – only flying mammal Wings – membrane between fingers Wings – membrane between fingers Different from birds and pterosaurs Different from birds and pterosaurs Nocturnal, often forest dweller Nocturnal, often forest dweller Eyesight poor Eyesight poor Well-developed echolocation Well-developed echolocation

Chiroptera Bats – only flying mammal Bats – only flying mammal Wings – membrane between fingers Wings – membrane between fingers Different from birds and pterosaurs Different from birds and pterosaurs Nocturnal, often forest dweller Nocturnal, often forest dweller Eyesight poor Eyesight poor Well-developed echolocation Well-developed echolocation Related to primates? Related to primates?

Dermoptera flying lemurs or colugos (2 species) flying lemurs or colugos (2 species) Squirrel size Squirrel size Gliders Gliders Skin stretched from neck, Skin stretched from neck, to forelimbs to backfeet Related to Chiroptera?

1 clade Primates Primates Dermoptera (flying lemur) Dermoptera (flying lemur) Tree shrews Tree shrews Chiroptera Chiroptera ?

Ungulata Order ARTIODACTYLA (even-toed ungulates eg. pigs, deer & cattle) Order ARTIODACTYLA Order CETACEA (whales and dolphins) Order CETACEA Order PROBOSCIDEA (elephants) Order PROBOSCIDEA Order SIRENIA (sea-cows) Order SIRENIA Order HYRACOIDEA (hyraxes) Order HYRACOIDEA Order PERISSODACTYLA (odd-toed ungulates eg. horses, tapirs and rhinos) Order PERISSODACTYLA Order TUBULIDENTATA (the aardvark) Order TUBULIDENTATA

“Cetartiodactyla “ Artiodactylids and cetaceans closely related! Artiodactylids and cetaceans closely related! Cetaceans evolved from artiodactylids Cetaceans evolved from artiodactylids

Cetartiodactyla Artiodactylids and cetaceans closely related! Artiodactylids and cetaceans closely related! Cetaceans evolved from artiodactylids Cetaceans evolved from artiodactylids Closely related to hippos, not pigs Closely related to hippos, not pigs Hippos grouped w/ pigs Hippos grouped w/ pigs

Artiodactyla 2 or 4-toed 2 or 4-toed line of symmetry passes between digits 3 & 4 line of symmetry passes between digits 3 & 4 Ankle structure differs from other ungulates (greater flexibility) Ankle structure differs from other ungulates (greater flexibility) pre-molars different from molars pre-molars different from molars

Artiodactyla Suborder Suina: Suborder Suina pigs, peccaries & hippopotami: most primitive, regrouped Suborder Tylopoda: Suborder Tylopoda camels & llamas Suborder Ruminantia: Suborder Ruminantia cattle, antelopes, deer and giraffes: advanced artiodactyls.

Cetacea Suborder Odontoceti (toothed whales) Suborder Odontoceti (toothed whales) Dolphins, killer whales, sperm whale Dolphins, killer whales, sperm whale Suborder Mysticeti (the baleen) whales. Suborder Mysticeti (the baleen) whales. Blue whale, right whales, humpback Blue whale, right whales, humpback

Proboscidea Proboscidea elephants - 2 genera, 2 species elephants - 2 genera, 2 species AsianAfrican AsianAfrican Tusks normally larger, both males & females have

Large, communal, herbivores Large, communal, herbivores

Eyes Eyes Small Small neck not very flexible neck not very flexible

Smell Smell Important Important touch with trunk, touch with trunk, move to Jacobson’s organ (roof of mouth) move to Jacobson’s organ (roof of mouth)

Teeth Teeth Incisors = tusk Incisors = tusk Molars – replaced from rear Molars – replaced from rear

Teeth Teeth Incisors = tusk Incisors = tusk Molars – replaced from rear Molars – replaced from rear Hearing and ears Hearing and ears Low frequency communication Low frequency communication Ears – thermoregulation Ears – thermoregulation

Trunk – very sensitive (tactile) Trunk – very sensitive (tactile) Respiration (snorkel for aquatic ancestor?) Respiration (snorkel for aquatic ancestor?) Hose for water Hose for water

Trunk – very sensitive (tactile) Trunk – very sensitive (tactile) Respiration (snorkel for aquatic ancestor?) Respiration (snorkel for aquatic ancestor?) Hose for water Hose for water Chemosensory & tactile Chemosensory & tactile

Trunk – very sensitive (tactile) Trunk – very sensitive (tactile) Respiration (snorkel for aquatic ancestor?) Respiration (snorkel for aquatic ancestor?) Hose for water Hose for water Chemosensory & tactile Chemosensory & tactile Picking up objects Picking up objects Communication – caress, threat displays, … Communication – caress, threat displays, …

Closest relative? Closest relative?

Closest relative? Sirenia! Closest relative? Sirenia!

Sirenia sea cows, dugongs, manatees (2 genera, 5 species) sea cows, dugongs, manatees (2 genera, 5 species) Large, slow moving herbivores Large, slow moving herbivores Usually solitary Usually solitary

Hyracoidea Hyraxes (3 genera, 11 species) Hyraxes (3 genera, 11 species) Africa Africa rabbit size, rodent-like animals rabbit size, rodent-like animals

Hyracoidea Hyraxes (3 genera, 11 species) Hyraxes (3 genera, 11 species) Africa Africa rabbit size, rodent-like animals rabbit size, rodent-like animals 4 toes in front, 3 in rear, hoof-like nails 4 toes in front, 3 in rear, hoof-like nails Rubbery soles – grip rock Rubbery soles – grip rock

Hyracoidea Hyraxes (3 genera, 11 species) Hyraxes (3 genera, 11 species) Africa Africa rabbit size, rodent-like animals rabbit size, rodent-like animals 4 toes in front, 3 in rear, hoof-like nails 4 toes in front, 3 in rear, hoof-like nails Rubbery soles – grip rock Rubbery soles – grip rock Related to elephants and Related to elephants andsirens

Perissodactyla line of symmetry down third digit line of symmetry down third digit a full set of incisors a full set of incisors greatly molarized pre-molars greatly molarized pre-molars

Perissodactyla line of symmetry down third digit line of symmetry down third digit a full set of incisors a full set of incisors greatly molarized pre-molars greatly molarized pre-molars 2 lineages – horses vs. tapirs & rhinos 2 lineages – horses vs. tapirs & rhinos Replaced by artiodactylids Replaced by artiodactylids

Tubulidentata Aardvarks – 1 species Aardvarks – 1 species Nocturnal, solitary, burrower Nocturnal, solitary, burrower Poor eyesight, Poor eyesight, Hearing and smell developed Hearing and smell developed Specialize in termites Specialize in termites Long sticky tongue Long sticky tongue Strong claws and forelimbs Strong claws and forelimbs digging digging