mammals

Question 1

monomermes

Answer 1

egg laying; e.g. platypus

Question 2

marsupial

Answer 2

pouched e.g. kangaroos

Question 3

placentals

Answer 3

e.g. gorilla

Question 4

mammalia development from synamsid

Answer 4

post orbital opening merges with orbit

Question 5

synapsids are

Answer 5

mammal like reptiles

Question 6

characteristics of mammals

Answer 6

mammary glands
hair
endothermic
homeothermic
diapgram, 4 chambered heart, red blood cells without nuclei
live birth (minus monotrmes)
heterodton teeth 
disphydonty
determinate growth 
secondary palate
single jaw bone
3 middle ear bones
repsirotory turbinates
large brains
double articulations 
upright posture

Question 7

mammal characteristics derived from fossilr ecord

Answer 7

heterodton teeth 
disphydonty
determinate growth 
secondary palate
single jaw bone
3 middle ear bones
repsirotory turbinates
large brains
double articulations 
upright posture

Question 8

heterodont teeth

Answer 8

different types of feeth

Question 9

dyphydonty

Answer 9

two sets of teeth

Question 10

secondary palate

Answer 10

seperate breating and feeding passages

Question 11

pelycosaurs

Answer 11

first synapsids
mammal ancestors
in fossil record 306 mya
had sprawling gait
quadrate articular jaw joint
nasal passages open into mouth

Question 12

synasid evolution

Answer 12

pelycosaurs
therapsids
cynadonts
mammal like reptiles
mammals

Question 13

what traits evolved into mammals

Answer 13

1. posture (sprawling to upright)
2. respiration (formation of secondary palate)
3. post dentary jaw bones to middle ear elements

Question 14

therapsids

Answer 14

275/200 mya
more upright stance
quadrate articular jaw joint but dentary expanding up and back
some taxa with partial or complete secondary palata

Question 15

cynodonts

Answer 15

255-170 mya
more upright posture
still quadrate articular jaw joint but post dentary jaw reduced
partial or complete secondary palate in all taxa
only two sets of complex teeht

Question 16

earliest mammals

Answer 16

210 mya; mainly small and insectivorous and nocturnal
upright gait
complete secondary palate
at first; both quadrate articular and squamosal jaw joint

e.g. harocosium (mous like)

Question 17

what did the articular and the quadrate evelop into

Answer 17

malleus and incus

Question 18

cenzoic

Answer 18

age of mammals

Question 19

meozoic

Answer 19

reptile age

Question 20

palezoic

Answer 20

synapsid age

Question 21

jurassic

Answer 21

mammalia evolution of shrews

Question 22

creatacous

Answer 22

large animals start evoling

Question 23

age of mammals

Answer 23

after k/pg extinction 65 mya;

mammals that made it through diverisifed quickly in terms of body size especially and specialization

Question 24

what are mammal clades based on

Answer 24

reproductive strategies

Question 25

placentals

Answer 25

long gestataion period, 5000+ species (95% of mammals)
diverse in numbers and types and biographic division

e.g. pangolins, armadillos, humans

Question 26

monotremata

Answer 26

egg laying
earlist fossils from creatcous
teeth in beke 
mammary glands without teets
no placenta

e.g. platapus echina duckbill

Question 27

marsupials

Answer 27

pouched animals
early createacous
south america and australia mainly
anticlockwize radiation around world

e.g. koala kangaroos oppposums

Question 28

4 major clades of placentals

Answer 28

1. laurosiatheria
2. eurochontoglieres
3. xenartha
4. afrotheria

Question 29

laurosiatheria

Answer 29

shrews bats carnivores

Question 30

eurochontoglieres

Answer 30

rabbits rodents primates

Question 31

xenartha

Answer 31

anteaters sloths south america

Question 32

afrotheria

Answer 32

elephants manatee africa

Question 33

atriodactyl

Answer 33

morphology of limb; nails to toes to feets; prupose to elongate limbs to move faster

e.g. whales closely repalted to hippos (ceetartiodatylus)

Question 34

angulates

Answer 34

tapirs, horses and rhinos, and whales

- walk on toes

Question 35

whatl developments

Answer 35

pakicetus to choohacetus to basilosaurus to modern whale

Question 36

pakicetus

Answer 36

50 mya wolf like mammals with enlogated skull and simplified teeth

Question 37

roohacetus

Answer 37

46 mya more specialized for water

webbed feed and elongated digits

Question 38

basilosaurs

Answer 38

37 mya

very whale like and elongated

Question 39

hippos to whales

Answer 39

transitional fossils show that teeth and balen devloved from hippo to modern whale ancesotrs