THE FINAL BABY. Flashcards
who is in Superorder Archosauria?
- crocodylomorpha (crocodiles and their relatives)
- dinosauria (dinosaurs including birds)
what happens if we add turtles as a basal/sister taxon to the Superorder Archosauria?
- we get a larger EXTANT clade referred to as Archosauromorpha
- this is why turtles are the only non-archosaurian archosauromorphs!
what order are all modern turtles in?
order testudinea
what are the suborders in order testudinea?
cryptodira and pleurodira
Describe the Suborder Cryptodira
- means hidden neck
- they are more widespread and diverse
- found in the northern and Southern Hemispheres
- NOT found in Australia
Describe the Suborder Pleurodira
- means side neck
- restricted to southern hemisphere currently, but were worldwide during Mesozoic and Cenozoic eras
Describe the Suborder Cryptodira
- means hidden neck
- more widespread and diverse
- found all over (not in Australia)
what is the carapace?
-the fusion between vertebrae and ribs
what makes the turtle morphology unique?
- their shell
- relocated shoulders and pelvises
describe the different pelvic morphologies of Pleurodira and Cryptodira turtles
Pleurodira: the pelvic assembly is fused to the carapace
Cryptodira: the pelvic assembly is not fused to the carapace
Neck retraction in Pleurodires and Cryptodires
- cryptodires have a high degree of vertebral flexibility and use the “vertical S bend” to hide their necks
- pleurodires have a longer neck and hide their neck using the “horitontal bend”
Family Dermochelyidae
- shell is reduced to thousands of small bones embedded in leathery skin
- contains the largest diapsids in this order (leatherback turtle)
Leatherback Turtle
- in family dermochelyidae
- fusion of vertebral elements different from other turtles
- because they are so large, they are able to save heat and therefore can survive where other turtles cannot
Family Cheloniidae
- the sea turtles!
- bony shells covered with epidermal scutes and paddle like forelimbs
- found world wide in tropical and temperate waters
Why are the Alligator Snapping Turtle and Sea Turtle so different, even though they both spend a majority of their life in water?
- they had different predators to evade, the AST had the alligator, while the sea turtles have sharks.
- also, AST are ambush predators and did not need to evolve to be hydrodynamically efficient
Family Chelydridae
- found in north and Central America
- large freshwater turtles
- alligator snapping turtle or common snapping turtle
Alligator Snapping Turtle
- purely ambush predator
- utilizes a lingual lure
- slow and heavy, not hydrodynamically efficient
Family Testudinidae
- tortises (mostly terrestrial)
- worldwide distribution in tropical and temperate climates
- NOT good swimmers
- designed to dig: heavily armored, flat paddle like limbs
- not much of a hinge, which means they can’t seal the plastron and use their limbs instead
When we see a turtle in family Testudinidae with a plastron, we know they are…
male!
Family Emydidae
- box turtles and cooters
- mostly in North America
- highly domed carapace (making it difficult for predator to bite)
- strongly hinged plastron
- not hydrodynamically efficient
Diamondback Terrapin
- unique Emydidae species
- flat shell with paddle like limbs (more hydrodynamic)
- males have long nails
Family Trionychidae
- soft shell turtles
- found in North America, Asia, and Africa
- basal lineage (ancestral)
- less fusion in ribs
- no keratinized outer cover
How are the soft shell turtles able to breathe under water?
projections at the back of the throat that are fleshy and highly vascularized
what are the male turtle morphologies?
- long penises
- long nails (aquatic species)
- spur on plastron
what are the archosauria synapomorphies?
- prescense of ant orbital fenestra
- orbit shaped like inverted triangle
- laterally compressed teeth
- 4th trochanter on femur
pseudosucha leads to…
- “such” relates to crocodylomorpha
assumed archosauria synapomorphies
- four chambered heart
- muscular diaphragm
- nest building/parental care
having laterally compressed teeth allowed carnivorous archosaurids to have…
serrations on their teeth
archosauria splits into two groups;
ornithodira (Dinos and birds) and pseudosuchia (crocs)
what does archosauromorpha split into?
the turtles and archosauria (dinos, birds, and crocs)
describe pangea prior to its split
pangea was one supercontinent surrounded by ocean, most of which were deep ocean basins.
deep ocean basins function as “heat sinks”, pulling heat out of the atmosphere. the climate had adapted to that but when pangea broke apart there were more shallow, tropical, marine waters releasing heat back into the atmosphere, warming it
what cause the end of Triassic extinction, and what were the results?
the change in environment and splitting of populations and possibly a meteor caused the extinction, which resulted in a mass extinction. pseudosuchia, which was previously very diverse all went extinct except for crocodylomorpha
all modern crocs are in…
neosuchia
what are the alligator families?
- alligatoridae
- crocodylidae (most diverse)
- gavialidae
crocodylian modes of locomotion
- lateral undulation (ancestral)
- belly crawl
- high walk
- gallop (rare and only in members of F. Crocodylidae)
What morphology is important for the high walk mode of locomotion in crocodylians?
the ankle and wrist joints can flex up and down AND laterally
reproductive behaviors of crocodylomorphs
- nest builders (mounds keep constant temperature)
- high degree of parental care (protection, providing food sources)
- creche: an area with babies from multiple females who then take turns taking care of the babies
predatory behaviors of crocodylomorphs
- generalist carnivores
- oportunistic
- ambush predators
- wait at high traffic areas
- “tool use”, luring in birds with sticks on snout
dermal pressure receptors
- a characteristic of crocodylomorphs
- concentrationsof mechanoreceptors that are very sensitive to movement in water, which allows them to successfully feed at night
inertial feeding in crocodylomorphs
- all crocodylomorphs do this to break their food into smaller pieces
- pushup + lateral head snap
- death roll
- heterodont dentition, so they dont chew
tenderizing behavior in crocodylomorphs
allows rigamortis to settle and the animal to rot + break down
clade ornithodira
divides into two groups; pterosauria (stem) and dinosauria/aves (crown)
pterosauria
- the first flying vertebrates
- late triassic to creassious-triassic extinction
- “hand” with three short fingers and elongate fourth finger
- pteroid bone in wrist
- short trunk
- short pelvis with prepubic bones
- diverse feeding models
describe ornithisia
ALL were quadrupedal herbivores, as indicated by their big bellies, dentition, and gastrolithes
describe saurichia
ALL identified to be quadrupedal herbivores, except the theropods, who are bipedal carnivores
what is the significance of maniraptora?
they begin looking familiar as birds
true or false, feathers predate birds
true!
therapod and bird synapomorphies
- hollow bones
- long, s shapes neck
- tridactyl foot
- digitgrade posture
- ankle joint intertarsal
- feathers
- furcula
- fused sternum
- egg brooding? sleeping postures
extant theropod dinosaurs
class aves
what is the more accurate name for class aves?
neornithines
true or false, archaopteryx falls into the same phylogeny of modern birds
true!
what is the significance of the archaopteryx fossil?
it is a very important fossil that supported Darwi’s theories, as it is a species with the skeleton of a lizard but there was soft tissue impressions indicating feathers.
- showed a transition to modern species
when did early birds radiate? (enantiornithines and ornithurines)
during the Cretaceous period
When did the extant birds (neornithes) radiate?
after the Cretaceous
as theropods evolved, there was a decrease in _______ overtime, why?
decrease in body size to facilitate with flying
birds in enantiornithes
sinornis and confuciusornis
birds in ornithurines
hesperornis and parahesperornis
clade neornithes splits into two lineages:
- infraclass palaeognathae
2. infraclass neognathae (splits into superorder galloanserae and superorder neoaves)
birds in palaeognathae
tinamous, emus, ostriches
birds in superorder galloanserae
fowl, ducks, and relatives
birds in r superorder neoaves
most modern birds
where are birds from Palaeognathae found?
all birds from this lineage are found on Gondwana land masses
the neoaves are divided into two groups:
the nonpasserines and the passerines, the latter of which have a unique foot morphology which allows them to easily perch on branches
What are the two lineages in Order Passeriformes?
Suboscines and Oscines
what is the difference between Suboscines and Oscines?
difference in syrinx allows oscines to have more complex, learned song.
streamlining and weight reduction in aves
- smooth junctions via overlapping contour feathers
- lack urinary bladder
- one ovary
- pneumatic bones
Describe the Pelycosaurs
- basal non-mammalian synapsids
- comprised of six paleozoic families, which disappeared at Permo-Triassic
- generalized amniotes, most of which were carnivores
- caseidae was an herbivorous family
Dimetrodon
member of family Sphenacodontidae, known as the sailback “dinosaur”
Describe the Therapsids
- middle Permian to early creaceous
- larger temporal fenestra
- more flexible limbs
- greater flexion of the neck
- differentiation of teeth (heterodont dentition)
Moschops and Sycoaurus
- Therapsid species
- represent a basal and derived therapsid
Describe the Cynodonts
- late permian through triassic
- reduction/loss of lumber ribs
- smaller size
- calcaneal heel (for the attachment of Achilles tendon)
- shorter tail
- enlarged infraorbital foramen
- multi-cusped cheek teeth
- derived species had enlarged olfactory lobes and cerebellums
Thrinaxodon
- basal cyonodont therapsid
Mammalia
- derived therapsids
- early “stem” mammals
- diphyodont teeth
- flexible backbone
- interlocking upper and lower teeth
- mastication with precise occlusion
- loss of cervical ribs
- very small
- larger olfactory lobes
- large neocortex
Megazostrodon and Morganucodon (Megazostrodontidae)
early mammaliaform, that were the size of shrews and insectivores
ventilation and locomotion (lizards vs mammals)
- lizards move through lateral undulation. as they bend laterally, air pressure moves from one lung to the next, but little to no air moves in or out of the animal, meaning they cant breathe while moving. however, as mammals gallop, the vertebral column bends, pressure rises and pushes air out. when it straightens, pressure in the lungs falls and air is pulled into the lungs
Why is the presence of a secondary palate in mammals (compared to lizards) important?
important for nursing
what do the turbinate bones in mammals do?
make the sense of smell in some mammals extremely sensitive
occlusion and dentition in a cynodont and early mammals
- cynodonts hace postcanine teeth that all look the same and move the jaw in a simple up and down movement
- in mammals, the teeth interdigitate on occlusion and the jaw movement is rotary, chewing on one side at a time.
ansiognathy
lower teeth are closer together than upper teeth (mammals)
trend in the skulls of non-mammalian synasids
increased size of temporal fenestra and coronoid process of the dentary
who are the crown group mammals?
mammalia
what are the groups in mammalia?
- Prototheria (monotremes)
2. Theria (the placentals)
What groups are in Theria?
Metatheria and Eutheria
Describe the Prototherians
- lay eggs
- groups included: Ornithorhynchidae and Tachyglossidae
- ineffective milk delivery
Characters of Ornithorhynchidae
- bird like nosed mammals
- platypus is the only surviving
- lack teeth
- currently only in Australia (historically in S. America)
- bill covered in leathery skin
- only mammale identified to have functional ampullae of lorenzini
- one of the few mammals knows to be venomous (males have enlarged claw)
Characters of Tachyglossidae
- the echidnas Genus Zaglossus (long nose, 3 species in New Guinea) - Genus Tachyglossus (short nosed, 1 species in Australia)
What is the significance of Microbiotheria?
it is the most basal in the Australidelphia lineage, however the only ones you find today are in South America (called the Monito del Monte)
what is the marsupial pouch called?
the marsupium
Where are marsupials thought to be from?
- thought to be from Gondwana land mass.
- moved to north america during the Great American Interchange via the land bridge
4 major orders within metatheria
- Didelphimorpha (ameridelphia)
- Dasyuromorpha (australidelpha)
- Peramelemorphia (australidelpha)
- Diprotodontia (australidelpha)
Didelphimorpha
- strongly nocturnal
- semi auboreal
- had to evolve with marsupials
prehensile tail
a tail that can act as a limb
Diprotodontia
- Phalangeridae & Tarsipedidae (possums)
- Vombatids & Phascolarctids (wombats and koalas)
- Macropodidae (kangaroo, wallaby)
Dasyuromorpha
Marsupial cats & marsupial mice
Peramelemorphia
Bandicoots and Bilbies
saltatorial
locomotion by jumping
