Intro Flashcards
What is Comparative Vertebrate Anatomy?
The study of vertebrates from an anatomical, Morphological, and evolutionary POV.
What is Morphology?
The study of the structure of organisms and their interactions between each other.
The study of how an organism grows- Usually related to an evolutionary aspect.
Ontogeny.
“Old-Saying” meaning you can observe evolution by investigating the developmental change and phases and organism goes through.
“Ontogeny recapitulates phylogeny”
Not a 100% true statement but very helpful to investigating phylogeny.
Theory describing evolutionary relationships between organisms.
“The Study of evolutionary relationships.”
Phylogeny.
The Mammoth and elephant are two different species that are expected to have come from a common ancestor, what is this an example of?
Divergent evolution.
Diverged from a common ancestor.
Koalas and humans both have unique fingerprints. We do not share a common ancestor, what is this an example of?
Convergent evolution.
Similar traits without shared ancestry.
7 Taxonomic ranks from most broad to specific
-Domain.
-Kingdom.
-Phylum.
-Class.
-Order.
-Family.
-Genus.
-Species.
What are the four/ five characteristics of chordates?
What does this mean?
-Notochard.
-Dorsal Hollow Nerve Cord.
-Endostyle.
-Post anal tail.
-Pharyngeal slits (Sorta/ Kinda).
All Chordates will posses these traits at some point within their life/ development even if not all at the same time.
What are the two closest relative phylums to chordates?
-Echinoderms
-Hemichordates
Two defining characteristics of echinoderms?
(Closely Related Phylum to Chordata.)
-5 sided radial symmetry
-Water vascular system.
(Use seawater instead of blood in a hydraulics fashion.)
EX: Sea stars and sea urchins.
4 characteristics of Hemichordata:
Part of Animalia Kingdom.
-Stomochord (like a rudimentary notochord.)
-“worm-like” body
-Dorsal nerve cord (sometimes hollow)
-Epidermal nervous system
EX: Acorn worms.
What are the 3 subphyla of chordata?
- Urochordata.
- Cephalochordata/ Craniata.
- Vertebrata.
Marine invertebrate chordates that do not retain all chordate traits at once and generally only keep the pharyngeal slits and endostyle?
Urochordata
EX: Tunicates or sea squirts.
Marine invertebrate chordates that have all 5 chordate traits throughout their life and are commonly used in diagrams because of this?
Cephalochordata
EX: Lancelets/ Amphioxus.
What is the notochord?
The 1st skeletal structure to appear in the embryo.
A rod like structure made of a “cartilage-like” substance “rudimentary backbone”.
What is the endostyle?
Ciliated Organ in invertebrate chordates that assists in filter feeding by secreting mucoid proteins.
This corresponds to the thyroid in most vertebrates.
Function of pharyngeal slits?
Respiration, & filter feeding- mostly in tunicates.
What is the first skeletal structure to develop within chordate embryo?
What is it’s placement?
Notochord: Dorsal to digestive tube and ventral to nerve cord. This will induce how the nerve cord forms.
What two classes of animals in chordata completely lose the notochord into adulthood?
Reptiles and birds.
What happens to the notochord in development of mammals?
It regress almost completely and expands as part of the center of intervertebral discs; The nucleus pulposus.
Sclerotome cells differentiated from somites lead to this regression and form the centrum of vertebrae.
What is the nucleus pulposus?
Gelatin middle layer of vertebral discs and what remains of the notochord.
What is the Annulis fibrosis?
The outer layer of vertebral discs made of fibrocartilage.
Strong, tough, and inflexible cartilage made of thick collagen fibers.
Fibrocartilage.
Are chordates the only phylum to possess a nerve chord?
No, however only chordata has a dorsal hollow nerve chord, while other nerve chords are likely to be ventral, such as arthropods and annelids.
The disc between the amniotic and yolk sac that will become the fetus within the amniotic sac.
What are it’s layers?
The Trilaminar disc. It’s layers are the ectoderm, mesoderm & endoderm. These three layers define a triploblastic organism.
What is the process of neurulation?
This is one of the earliest steps in nervous system development where the cells in the dorsal neuroectoderm above the notochord go through rapid mitosis and form a concave neural groove that sinks & eventually closes up into the Neural Tube. (Dorsal & Hollow.)
Name this Process
Shown in Transverse plane!
Neurulation W/ Neural groove.
What is something the occurs at the same time as neurulation which leads to the ball of cells looking like a fetus within the amniotic sac?
Embryonic folding
Saggital Vs. Transverse planes.
What is the Pre-structure before the neural tube?
Neural groove.
Which organisms neurulate differently and what is different?
Agnathans & Neopterygians.
They will form a neural keel instead that will then form the Neurocoel and detach from the dorsal ectoderm creating the hollow dorsal nerve.
Agnatha is broad “Class”. Neopterygii is a large “Order”.
What is the neural keel?
The wedge shaped structure made from ectodermal cells that will differentiate into the hollow nerve cord. A different neurulation process used by Agnathans & Neopterygians.
What is this process?
Neurulation W/ Keel.
What is unique to vertebrata?
They will always have a distinguishable head, trunk, and Tail.
What are Vertebrate Tetrapods?
What is something they possess?
An organism with four feet/ limbs.
They will a possess a neck.
Developmental processes resulting in formation of the head?
Cranialization or Cephalization.
What are jawed vertebrates called?
Gnathostomata.
What will the head contain in vertebrates (4)?
The brain, specialized organs, +/- jaws (Gnathostomata.), +/- gills.
What are agnathans and why are they in vertebrata?
Jawless fish. They still have a well defined head have sort of rudimentary vertebrae made of cartilige, or could be able to form vertebrae.
They are known to be the earliest vertebrates.
What is the central region of the body called?
The trunk.
What is the coelom?
What is made from?
What surrounds the coelom?
A structure (usually embryonic) that is a fluid filled cavity that will go on to house visceral organs.
The coelom is formed by the mesoderm and surrounded by the body wall (vertebra, ribs, and somatic muscles.)
What is something terrestrial vertebrates started to possess in early evolution?
Neck.
What are the two groups of symmetry in animals, which is specific to vertebrates?
Radial and bilateral.
Bilateral in vertebrates.
Which Body Plane?
Transverse
Separates Cranial and Caudal parts.
Which Body Plane?
Dorsal plane
or, Frontal Plane
& Coronal plane in humans.
Separates ventral and dorsal regions, posterior and anterior in humans.
Which Body Plane?
Mid Saggital.
Which Body Plane?
Para Sagittal.
What vertbrate feature is caudal to the trunk?
The post anal tail.
The tail is posterior to the anus.
What is metamerism? Name an example:
A serial repetition of structures along the long axis of the body, more prevalent during development. EX: Ribs.
Neopterygians?
Part of Actinoperygii (Ray Finned Fish).
Divided into Teleostei & Holostei.
What are the two divisions within Agnatha?
- Myxini (Hagfish.)
- Cephalospidiformes (Lampreys.)
What are the 6 divisions of Gnathostomata?
“Jawed Vertebrates”
1. Chondrichthyes.
2. Osteichthyes.
3. Amphiba.
4. Reptilla.
5. Aves.
6. Mammals (Most Modern.)
What are Chondrichthyes?
Cartilaginous Fish.
* Mostly Hyaline, Jaws mineralizaed.
* Placoid Scales.
* Ectothermic.
Divided into Elasmobranchii & Holocephali.
What are Elasmobranchii?
Sharks, Rays & Skates.
* 5-7 Visible Gill Slits/ No operculum.
* Upper Jaw not fused to cranium.
Part of Chondrichthyes.
Divided into Selachimorpha & Batoidea.
Elasmobranch= “Naked Gill”
What are Selachimorpha?
“True Sharks”
* Fusiform Body.
* Heterocercal Tail- upper lobe is larger.
* Fins are triangular or sickle sharped.
Part of Elasmobranchii.
Divided into Carcharhiniformes, Lamniformes, Heterodontiformes, Orectolobiformes, Pristiophoriformes, Squaliformes, & Hexanchiformes.
Fusiform: Tapered at both ends “Torpedo”
Herocercal: Assymetrical
Lamniphormes?
Part of Selachimorpha.
Mackerel Sharks: Fast Swimming Powerful Sharks.
* Conical Snout.
* Streamlined slender body.
* Pelagic Feeding behavior.
* Large & Sharp Serrated Teeth.
* Long Gill Slits.
EX: Great White, Mako, Thresher & Basking sharks (Only Filter Feeder).
Carcharhiniformes?
Part of Selachimorpha.
Ground Sharks.
* Broader head than other sharks.
* Broader body.
* Usually 2 evident dorsal fins.
* Caudal Pelvic Fins.
* Benthic Feeding behaviors.
EX: Bull, Blacktip, Sandbar, Hammerheads, & Catsharks.
Heterodontiformes?
Part of Selachimorpha.
Bullhead sharks.
* Wide flat head.
* Short blunt snout.
* Short Stocky Bodies.
* Two Spiny Dorsal Fins.
* Benthic Feeders & Bottom Behavior.
* Mostly Oviparous.
EX: Horn and banded bullhead Sharks.
Orectolobiformes?
Part of Selachimorpha.
Carpet Sharks.
* Elongated Flattened Bodies.
* Slow moving Bottom Dweller/ Ambush Predator.
* Ventral Mouth & grasping teeth, not cutting.
* Barbels.
* Mostly Viviparous.
EX: Wobblegong & Nurse Sharks.
Pristiophoriformes?
Part of Selachimorpha.
Saw Sharks.
* “Saw-like” Snout.
* Long slender bodies, long tail.
* Many have barbels.
* Oviviparous.
EX: Saw Sharks.
Squaliformes.
Part of Selachimorpha.
Dog Fish Sharks.
* Deep Water Adapted.
* Small-Medium slender body.
* Spiny Dorsal Fins.
* Lack Anal Fin.
* Mostly Oviviparous.
EX: Dog Fish Gulper, Greenland, & Sleeper Sharks.
Hexanchiformes?
Part of Selachimorpha.
Cow Sharks.
* 6-7 Gill slits, Basal Feature, (Sharks Usually have 5)
* Robust cylindrical body.
* Long upper tail lobe (Heterocercal).
* Ventral Mouth.
* Oviviparous.
EX: Bluntnose 6 Gill & Sharpnose 7 Gill Sharks.
Batoidea?
Part of Elasmobranchii.
Cartilagenous Fish (Rays & Skates).
* Flatted “disc-like” bodies.
* Benthic feeders.
* Flattened “plate-like” teeth and ventral mouths.
* Usually Viviparous.
* Spiracles behind eyes.
Divided into: Rajiformes, Pristiformes, Myliobatiformes, & Rhinobatiformes.
Spiracles: Small opening/ pore which draws water into the gill chambers.
Rajiformes?
Part of Batoidea.
Rays & Skates.
* Flattened Disc shape body.
* Wing-like pectoral fins.
* Benthic Dwellers.
* Digging behavior.
* Mostly Oviparous.
* Shortish whip like tail.
EX: Skates, stingrays, & electric rays.
Pristiformes?
Part of Batoidea.
Saw Fishes.
* Elongated snout with teeth along the edges.
* Streamlined elongated body.
* Long muscular tail which is heterocercal, larger upper lobe.
* Has both flat teeth for crushing and sharp teeth.
* Viviparous.
* Ventral Gills- Like a Ray/ Not Shark.
* No Barbels.
EX: Small tooth, Large tooth, & Green Sawfish.
Myliobatiformes?
Part of Batoidea.
Eagle & Manta rays.
* Flattened diamond shaped bodies.
* Viviparous.
* long “whip-like” tail.
* Pelagic.
EX: Manta, Eagle, and Devil Rays.
Holocephali?
Part of Chondrichthyes.
Chimeras/ Rat fish/ Ghost sharks.
* Placoid scales.
* Cartilagenous Skeleton.
* Singular gill slit on each side of head.
* Flat Grinding Teeth.
* Elongated bodies & long tails.
* Wing-like pectoral fins.
* Large Eyes suited for dim deep benthic.
EX: Chimeras/ Rat fish/ Ghost sharks.
divides further, only extant order is chimaeriformes.
Osteichthyes?
Part of Gnathostomata.
Bony Fish.
* Skeleton of 2(Ca3PO4)
* Ectothermic.
* Swim Bladder.
* Scales: Leptoid & Ganoid.
* Bony Operculum.
Divided into Actinopterygii & Sarcopterygii.
Calcium Phosphate.
Actinopterygii?
Part of Osteichthyes.
Ray Finned Fish.
* Fins Supported by thin segmenting rays.
* Fins are thin and flexible.
* More ossified than Sarcopterygii.
Further divided into Chondrostei & Neopterygii.
Sarcopterygii?
Part of Osteichthyes.
Lobe Finned Fish.
* Fins are fleshy and muscular. Central Bony core similar to tetrapods.
* More cartilage in bones than acintopterygii.
Further divided into Dipnoi & Actinista.
Chondrostei?
Part of Actinopterygii.
Cartilagenous-like Fish.
* Skeletons are partially cartilage.
* Ganoid Scales.
* Heterocercal tail, longer upper lobe.
Only extant group is Acipenseriformes:
EX: Sturgeons, Paddlefish, Bichirs.
Neopterygii?
Part of Actinopterygii.
more Modern Ray Finned Fish.
* Homocercal Tail.
* Larger Ossified vertebrae.
* Fewer and lighter bony skull elements.
* More efficient and functional Swim Bladder.
Divided into Holostei and Teleostei.
Homocercal= Equal size lobed tail.
Holostei?
Part of Neopterygii.
More primitive then neopterygii.
* Ganoid scales.
* Somewhat heterocercal tail, upper a bit larger.
EX: Bowfin, and Gars.
Teleostei?
Part of Neopterygii.
* Light & Flexible Ossified skeletons.
* Premaxilla can move independently.
* Developed & Efficient swim bladder.
* Flexible, Ossified vertebral column.
* Modified Gill arches.
* Homocercal Tail.
* Leptoid Scales.
Further divdes into Many diverse orders, the most diverse and advanced group of fish.
Dipnoi?
Partof Sarcopterygii.
Lungfish.
* Obligate air breathers- Depend on lungs over thier gills.
* Lung/ Modified Swim Bladder.
* Adapted for Estivation.
* Elongated cylindrical body.
* “limb-like” fins.
* Retained primitive olfactory bulb.
* Ganoid Scales.
Actinista?
Part of Sarcopterygii.
Ceolacanths.
* Fleshy/ lobed “limb-like” fins.
* Heterocercal tail, larger upper.
* Relatively large brain.
* Retained olfactory bulb.
* Oil filled swim bladder.
* Conical Teeth used for a suction feeding mechanism.
* Cosmoid Scales.
Amphiba?
Part of Gnathostomata.
Amphibians.
* Biphasic Life: start with gills/ aquatic and move to terrain/ lungs.
* Mucus Type epidermis with respiratory function.
* Ectotherms.
* External Fertilization.
* Mostly oviparous.
* 3 chambered heart.
only extent division is Lissamphiba.
Lissamphiba divides into Anura, Caudata, & Gymnophonia.
Anura?
Part of Amphiba.
Frogs & Toads.
* No adult tail.
* Limbs adapted to jumping.
* Oviparous- only known Viviparous is the west african nimba toad.
* Primarily External Fertilization.
Urodela/Caudata?
Part of Amphiba.
Salamanders & Newts.
* Tailed Adults.
* Elongated Bodies
* Limbs at 90º to the body.
* Primarily rely on cutaneous respiration.
* Primarily internal fertilization.
* Mostly Oviparous.
Apoda/ Gymnophonia?
Part of Amphiba.
Caecilians.
* Limbless worm-like body.
* Pair of sensory organs on head known as tentacles.
* Poor eyesight.
* Rely on Cutaneous respiration.
* Rudimentary lungs.
* Mostly internal fertilization.
* Mostly oviparous.
Reptilla?
Part of Gnathostomata.
Reptiles.
* Ectothermic
* Scaled keratinized epithelium.
* Amniotic Eggs.
* Internal Fertilization.
* Lungs for respiration.
* Mostly Oviparous.
* 3 chambered heart with partial separtion of ventricle.
Divided into Anapsida & Diapsida.
Reptile Scales Vs. Fish?
Fish scales are derived from the dermis (Mesoderm).
Reptile scales derive from the epithelium (Ectoderm for the skin specifically.) so they are also known as epithelial scales.
Reptile skin is keratinized while fish skin is mucus type.
Epithelium can be derived from all three germ layers.
Types of Amphibian Eggs?
Anamniotic: Lacking amniotic sack.
Isolecithal: Small Central yolk.
Mesolecithal: Intermediate yolk.
What classes are amniotes?
Reptilla, Aves, & Mammalia.
What is an amniote?
Tetrapod adapted to lay a terrestrial egg &
Embryo develops in an amnion: A thin membrane forming a closed sac around the embryo/ fetus.
Diapsida?
Extant group of Retilla.
* Mosly have Temporal Fenestra
Further divided into Testudines, Crocodylia, Sphenodontia, Squamata.
Temporal Fenestra: Skull openings behind the eyes.
What is a mudpuppy?
Salamander.
Necturus.
Live around ~11 yrs, ~30 in captivity.
Neotenic- Permanent Larval State.
Testudines?
Part of Reptilla.
Turtles, Tortoises, & Terrapins.
* 2-part Bony Shell. (Carapace-upper, Plastron-lower).
* Keratinized Beaks- No teeth.
Crocodylia?
Part of Reptilla.
Crocodiles, Alligators, Caimans, & Gharials.
* 4 chambered heart.
* Long Muscular Bodies.
* Short Legs, & Webbed feet.
* Osteoderms
* Internal Nostrils. Can close nostrils and throat.
Sphenodontia?
Part of reptilla.
Only extant division is Tuataras.
* Endemic to New Zealand.
* Parietal “3rd eye” & photosensitive- poss. involved W/ Circadian & Hormones.
* Two rows of upper teeth, one row of bottom teeth.
Squamata?
Part of Reptilla.
Lizards, Snakes, & Amphisbaenians.
* Kinetic Skull
* Sharp backward curved teeth.
* Some have limb reduction such as snakes.
* Forked Tongue.
* Vomeronasal organ.
* Further divides into: Lacertillia, Serpentes, & Amphisbaenians.
Animals With kinetic Skulls have a further ability to move their jaws to allow larger prey to fit.
Lacertilla?
Part of Squamata.
Lizards.
* 4 Well Developed Limbs
* Mostly Diurnal.
* Many Posses Autonomy.
EX: Geckos, Skinks, Chameleons.
Autonomy abiliy to lose thier tail as a defense mechanism.
Serpentes?
Part of Squamata.
Snakes.
* Limbless.
* No eyelids- they have a transparent scale which also sheds.
* Differing movement types: Lateral Undulation, Sidewinding, & Rectilinear.
EX: Pythons, Boas, Cobras, Vipers, & Sea snakes.
Lateral Undulation: Wave-like Pattern.
Sidewinding: Used in sand mostly- snake moves sideways useing wavelike pattern to push itself- fast.
Rectilinear: Linear movement- like an earth worm.
Aves?
Part of Gnathostomata.
Birds.
* Feathers.
* Beak/ Bill.
* Lightweight hollow skeleton.
* Endothermic.
* Oviparous Amniote eggs.
* Air Sac System.
Further divided into Paleognathae & Neognathae.
Paleognathae?
Part of Aves.
Ratites and Relatives.
* Mostly Flightless.
* Large Body Size.
* Retain Pneumatic Bones.
* Simplified Palate.
* Strong Legs.
* Large Amniotic Eggs.
Further divided into many orders.
EX: Ostriches, Rheas, Cassowaries, Emus, Kiwis.
Not Penguins!
Pneumatic Bones: Hollow Bones Filled with Air & Connected to Repiratory System.
Neognathae?
Part of Aves.
Modern Birds.
* Flight and Flightless birds.
* More complex Palate and Pneumatic bones.
Further divides into Many orders.
EX: Penguins, Ducks, Birds of Prey, Pelicans, Chickens, Turkeys, Parrots, Sparrows, doves, Cranes, Kingfishers and many more.
Mammalia?
Part of Gnathostomata.
Mammals.
* Mammary Glands.
* Hair/ Fur.
* Endothermic.
* Viviparous- Monotremes exception (Oviparous).
* Amniotic.
* 3 Middle ear bones.
Further divides into Prototheria, Metatheria & Eutheria.
Protheria.
Only extant order: Monotremes.
Part of Mammalia.
Monotremes.
* Oviparous, leathery eggs, but still have an amnion.
* Mammary Glands.
* Cloaca.
* lower metabolism than other mammals.
* Many have Electroreception
Only Extant Order is Monotremes.
EX: Platypus, & 4 various Echidnas are the only extant species.
Group of mammalia most closely related to reptilla.
Are Mammals closer to Aves or Reptilla?
Reptilla.
Both mammals and aves arose from reptilla at different times, reptilla diverged from an amniote ancestorn into diapsida and synapsida ~350 m.y.a. Mammals arose/ diverged from synapsida first, ~150 m.y.a. Aves arose/ diverged from Diapsida ~150 m.y.a. Diapside also led to most modern reptiles today.
Time periods; Just Observe.
Metatheria?
Part of Mammalia.
Marsupials.
* Viviparous Extremely Altrical Young, many finish development in an external pouch.
* Female: 2 Uteri & Vaginas, Male: Corresponding Hemipene/ Bifurcated Penis.
Diverge into Ameridelphia & Australdelphia- Based on where the species developed/ Evolved.
Americas: Opossums & Monitodel monte.
Australia & New guinea: Kangaroos, Koalas, Wombats, Tasmanian Devil, Bandicoots, etc.
Altrical
Eutheria?
Part of Mammalia.
Placental Mammals.
* Viviparous young which develop in a placenta within uterus.
* Mostly Altrical, but also Precocial.
* Larger Brain to body size Ratio.
* Typically Single uteri.
What region of the Body houses the Ceolom?
Trunk
What the Ceolom House?
Visceral Organs.
The Ceolom in the Trunk houses the visceral organs and is surrounded by the body wall. What are the Body Wall’s Components?
- Muscle.
- Vertebra.
- Ribs.
Gnathostomata, the Jawed Vertebrates will also typically have what type of structures?
Paired Pelvic and Pectoral appendages (Wings, Fins, Legs etc.)
What two Classes of Vertebrata Retain the Notochord?
Fish (Osteichthyes & Chondrichthyes.)
&
Amphibians.
Process of forming the neurochord?
Neurulation.
What is this Process?
Neurulation W/ Neural Keel.
How is the brain formed?
The Nerve Cord will expand Anteriorly and form the Brain.
Squalus?
Genus of Spiny Dog Fish.
Live to about 35/45 even up to 70!
