Amniote Lecture Flashcards
(105 cards)
1
Q
Amniote synapomorphy
A
amniotic egg (clade-defining)
2
Q
Amniote monophyletic or paraphyletic?
A
monophyletic clade
3
Q
Amniotic egg “synapomorphies” (3)
A
(3 new membranes)
- Amnion
- Allantois
- Chorion
4
Q
Amnion
A
surrounds developing embryo & holds it in amniotic fluid (“enclosing the pond”)
5
Q
Allantois
A
repository for nitrogenous waste
6
Q
Chorion
A
gas exchange (together with Allantois)
7
Q
Other derived characteristics of Amniotes (8)
A
- keratinized skin (resistant to water loss)
- keratinized epidermal scales in reptiles (dermal in bony fishes) (epidermal + dermal in cartilaginous fishes)
- hardened nails or claws
- ventilation/respiration via lungs filled by thoracic expansion (expansion of rib cage produces (-) pressure)
- no larvae or metamorphosis
- no gills
- loss of lateral line system
- internal fertilization (most w/ intermittent organ)
8
Q
Amniotes originated in
A
early carboniferous
9
Q
3 major groups of amniotes by
A
later carboniferous (based on skull morphology)
- Anapsida
- Diapsida
- Synapsida
10
Q
Anapsida =
A
first amniotes! (extinct?)
11
Q
Anapsida have no
A
no temporal skull opening behind orbits (completely roofed by dermal skull bones)
12
Q
Turtles historically considered
A
Anapsids
13
Q
Turtles now considered
A
derived Diapsids based on new data
- t.f. no extant anapsids
14
Q
Diapsids have
A
2 temporal skull openings behind orbits (separated by bony arch)
15
Q
Diapsids represented today by
A
all living reptiles & birds
16
Q
Diapsida =
A
Testudines, Lepidosauria, Archosauria
17
Q
Testudines (turtles) monophyletic or paraphyletic?
A
monophyletic clade
18
Q
Lepidosauria monophyletic or paraphyletic?
A
monophyletic clade
19
Q
Archosauria monophyletic or paraphyletic?
A
monophyletic clade
20
Q
Testudines girdle located
A
w/in rib cage
21
Q
Testudines lack
A
teeth (jaws w/ keratinized plates)
22
Q
Testudines reproduction
A
oviparous & bury eggs in nests
23
Q
Testudines sex det
A
Incubation Temperature Dependent Sex Determination
24
Q
What groups exhibit Temperature Dependent Sex Determination?
A
all turtles, crocodilians, some snakes & lizards
25
Temperature Dependent Sex Determination:
high temp = female
low temp = male
~29 degree switch threshold
26
Current phylogenetic position of Turtles?
- closer to derived diapsids:
DNA evidence says closer to Archosaurs (crocs & birds)
Morphological evidence says closer to Lepidosaurs (snakes & lizards)
27
Transitional turtle
Odontochelys semitestacea ("toothed turtle with half shell")
- most basal turtle
- teeth!
- only bottom half of shell present
28
Lepidosauria is w/in
Diapsida
29
Testudines is w/in
Diapsida (current)
30
Rhynchocephalia is w/in
Lepidosauria t.f. Diapsida
31
Lepidosauria animals consists of
all non-avian reptiles except crocs & turtles
32
Lepidosauria =
Rhynchocephalia (tautara) (most basal lineage) + Squamata (lizards)
33
Archosauria is w/in
Diapsida
34
Squamata is w/in
Lepidosauria t.f. Diapsida
35
Serpentes is w/in
Squamata t.f. Lepidosauria t.f. Diapsida
36
Amphisbaenians is w/in
Squamata t.f. Lepidosauria t.f. Diapsida
37
Rhynchocephalia aka
"tuatara" aka living fossil
38
Rhynchocephalia species
one one extant
39
Sister lineage to Squamata
Rhynchocephalia
40
Squamata =
Lacertilia (lizards) + Serpentes (snakes) + Amphisbaenia
41
Lacertilia is w/in
Squamata t.f. Lepidosauria t.f. Diapsida
42
Lacertilia (lizards) monophyletic or paraphyletic?
paraphyletic group (when snakes & amphisbaenians not included)
43
Serpentes (snakes) monophyletic or paraphyletic?
monophyletic clade
44
Squamata integument
periodically shed in 1 or large pieces
45
Squamata skulls are
kinetic skulls = significant movement of different parts of the skull relative to e/o
46
Squamata synapomorphies
- hemipenes: paired intermittent organ
| - tail autonomy (lost in snakes & in some lizards)
47
Lacertilia feeding
most insectivorous
some large ones are herbivorous
some carnivorous on large prey
48
Lacertilia tail autonomy
fracture planes w/in vertebrae (how lizards regrow tails)
49
Squamata limblessness derived
convegently (evolved independently) btwn snakes & lizards
50
Amphisbaenia characteristics
- limbless (except one family w/ front limbs)
- one lung (L)
- fossorial (adapted for burrowing)
- robust akinetic skull used as burrowing organ
51
Amphisbaenia feeds on
mostly invertebrates
52
Serpentes occupy which habitats
all except antarctic
53
Serpentes lack (2)
- limbs (some forms w/ pelvic girdle vestiges)
| - external ear openings
54
Serpentes eyelids
fused into spectacle
| - lower eyelid of snake always closed & one of the scales became spectacle
55
Serpentes lungs
```
only one (R) (opposite of amphisbaenians)
- why? no reason, LOL, just happened
```
56
Serpentes feeding
all carnivorous
57
Serpentes amount venomous
only <15%
58
Serpentes feeding specializations
skull extremely kinetic (parts moveable relative to e/o)
- paired joints on each side of head increase gape
- mandibular symphysis unfused (lower jaws move separately on each side to ingest large prey)
59
Archosaurian animals
crocodilians, birds, & extinct groups (pterosaurs, dinosaurs, etc)
60
Archosaurian flight evolved
twice (pterosaurs & birds)
61
Crocodylia is w/in
Archosauria
62
Most basal archosauria
Crocodylia
63
Crocodylia teeth =
thecodont (teeth in sockets)
64
Crocodylia oviparous or viviparous?
oviparous (egg laying)
65
Crocodylia sex determination?
temperature dependent
66
Crocodylia exhibit complex
vocalizations (associated w/ courtship, territoriality, etc)
67
Crocodylian parental care
nest guarding & taking young to water in mouth
68
Possible archosaur synapomorphies:
complex vocalization & nest guarding...
| both in crocs & birds
69
Crocodylian secondary palate
separates breathing & eating pathway
70
birds and mammals are both
endotherms
71
Shared characteristics between non-avian reptiles & birds
- 1 middle ear bone (stapes)
- mandible (consists of several bones) (articulates w/ quadrate)
- excrete N-wastes as uric acid (urea in mammals)
72
Dinosaurs monophyletic or paraphyletic?
paraphyletic if birds not included
73
Therapoda =
various Dinos + birds
74
Aves aka
birds
75
Aves synapomorphies (6)
- bipedal
- neck (elongate, mobile, S-shaped)
- pneumatic (hollow) bones
- digitigrade posture (walks on digits)
- furcula (fused clavicles = "wishbone")
- lunate carpals (allow swiveling movements key to flight)
76
Most basal bird
Archaepteryx
77
Archaeopteryx characteristics (therapod & bird)
"old + wing"
- therapod (non-bird) char.'s = thecodont teeth, long tail, clawed digits on forelimbs
- bird char.'s = asymmetrical feathers t.f. probably capable of true flight
(clearly shows bird-theropod relationship)
78
Neornithes is w/in
Aves
79
Neornithes monophyletic or paraphyletic?
monophyletic clade (including all extant birds)
80
Neornithes major radiation during
Cretaceous & early Tertiary
81
Neornithes =
Paleognathae + Neognathae
82
Intermittent organ in birds?
not in most (ostriches & ducks do tho)
83
Paleognathae aka
"ratites"
84
Paleognathae is w/in
Neornithes t.f. Aves t.f. Archosauria t.f. Diapsida
85
Paleognathae animals
ostriches (largest living bird), emus, kiwis, etc
86
Paleognathae flight?
flightless (have flat sternum)
87
Neognathae is w/in
Neornithes t.f. Aves t.f. Archosauria t.f. Diapsida
88
Neognathae animals
all other birds (besides paleognathae)
89
Neognathae flight?
* but...
* & evolutionary pattern?
strong flight muscles (keeled sternum)
* but flightlessness evolved independently (convergently) many times due to loss of keel
* & reversal/secondarily derived
90
Bird feathers homologous to?
scales of other reptiles
91
Bird feather origin?
epidermal (t.f. homologous to scales or reptiles)
92
Bird feathers made of
keratin
93
Bird feathers are functional when
they are dead
94
Other bird feather functions:
- thermoregulation (conserve body heat)
- flight (flight feathers)
- social displays (elaborate & colorful)
- bristles around mouth of some birds (sensory function that catches insects in flight)
95
Bird skeletal specializations
- pneumatic bones (filled w/ air cavities, strong but light)
- skull (lightly built "loss/reduction vs. ancestral archosaurs")
- teeth lost (replaced by keratinized beak)
- axial skeleton (sternum w/ carina "keel" for powerful flight muscle attachment, & furcula "fused clavicles" that acts as a stabilizing strut)
96
Birds and endothermic w/
high body temperatures & high metabolic rate (requiring large food intake)
97
Bird metabolism evolved
- crop = storage chamber @ end of esophagus that increase digestive capacity
- gizzard = compartment of the stomach that grinds food w/ keratinized plates (replacing role of teeth)
98
Beak evolution due to
feeding specializations
99
gas exchange in birds is...
the most efficient (related to high metabolic rate and energetic demands)
100
bird gas exchange modifications (2)
- parabronchi = site of gas exchange (rigid lungs) that increase gas-exchange capacity (huge surface area, & thinnest gas-exchange membranes among vertebrates)
- air sacs = expand/contract to ventilate parabronchi (poorly vascularized elastic structures) increase volume of air sacs several times that of parabronchial lung, making body lighter
101
pattern of air flow though bird parabronchi
unidirectional & continuous
102
Structures on bird vertebrae show
non-avian dinosaurs had air sacs in same places as birds
103
vision in birds
- large eyes (eagles & owls have eyes size of humans)
- high acuity color vision (active & coordinated habits)
- retina w/ high density of rods & cones (to see in difficult to see environments)
104
birds mate
| *but
monogamous
- both sexes equally capable of caring for young
- females gestate young & lactate
* but, DNA paternity analysis shows birds as "unfaithful"
- cuckoldry (poor guy lol)
105
what 2 things matter most in life????
energy & reproduction!!!!
