AD unit 4 Flashcards
synapomorphies of Echinodermata
Pentaradial symmetry, Larvae bilaterally symmetrical; Calcium carbonate endoskeleton; WVS
Common deuterostome characteristics?
blastopore doesn’t become mouth, enterocoelous development, radial indeterminate cleavage
Echinodermata characteristics
Marine; benthic predators, detritivores, herbivores or suspension feeders
what are Asteroidea?
sea stars
Major Echinoderm Subgroups
Asteroidea, Ophiuroidea, Echinoidea, Holothuroidea, Crinoidea
what are Ophiuroidea?
brittle and serpent stars
what are Holothuroidea?
sea cucumbers
what are Echinoidea?
urchins, sand dollars
what is the skeleton of articulated plates made of in Asteroids?
calcium carbonate
what are Crinoidea?
sea lillies
what are the key features of the external anatomy of an Asteroid?
interambulacral + ambulacral regions; pper surface w pedicellariae (pincers on stalks); Mouth faces down, anus on top (aboral surface)
what is the internal anatomy of an Asteroid?
body filled w perivisceral coelom (PVC)
how does the WVS work?
Ends are tube feet; Radial canals run down arms in ambulacral grooves, Along radial canals are ampullae, 1 above each tube foot, Contract, tube feet expand/attach; relax and muscles contract, it moves; Ring canal (RC) encircles mouth; Stone canal connects RC to madreporite (sieve plate) on aboral surface
what is the Water Vascular System?
coelomic tube system filled w seawater
what are tube feet?
tentacles used for locomotion/prey capture
what do asteroids eat?
How do asteroids eat?
evert stomach thru mouth, no/small anus
nervous system characteristics of Asteroids
nerve net w ring nerve under RC; radial nerve extends into each arm
gas/waste characteristics of Asteroids?
occurs across tube feet; papullae aid respiration; PVC transports O2
what is the hemal system in Asteroids?
Ophiuroidea (brittle/serpent stars) general anatomy
5 slender arms w round central disk; Mouth w 5 jaws, madreporite on oral surface; no anus; Radial nerves covered by plates (closed ambulacral groove)
what are Holothuroidea’s?
elongated, soft echinoids
Echinoidea (urchins and sand dollars) general anatomy
Round/flattened _____ w spines, pedicellariae (small wrench/claw-shaped appendage w movable jaws (valves); Gonopores, madreporite, terminal tube feet open thru 5 apical plates; closed ambulacral groove
what are Cuvierian tubules?
modified parts of respiratory trees; stick threadsd
What other animals have tripartite coeloms?
lophophorates, echinoderms
general anatomy of Holothuroidea’s?
stone canal leads to internal madreporic bodies; respiratory trees for gas exchange
how are Cuvierian tubules used and what for?
what is Evisceration?
when harassed/stressed sea stars dump their guts
what are the 3 body regions of Hemichordata?
proboscis, collar, trunk - each w coelom
what are Pterobranchia?
marine colonial tube dwellers; deep sea
what are Enteropneusta?
marine benthic worms; solitary, acorn worms
how do Enteropneusta eat?
eat particles that stick to proboscis; water flows into mouth, out thru pharyngeal slits
where does gas exchange occur in Enteropneusta?
pharyngeal slits
Major synapomorphies of Chordata include:
notochord, postanal tail, endostyle, DHNC, pharyngeal slits/pouches
what is a notochord?
flexible dorsal skeletal rod, replaced by vertebrae in most verts
what are the major subgroups of Chordata?
Cephalochordata, Urochordata, vertebrata
what is a postanal tail?
vestigial, lost in few verts
where in the endostyle in humans?
thyroid gland
what are lancelets?
suspension feeders in shallow, warm marine habitats
what is Cephalochordata?
lancelets
what diagnostic chordate features are found in Cephalochordate adults?
V-shaped myomeres
how do Ascidiacea reproduce?
cloning - form colonies; sexual - Hermaphroditic, occasional self fertilization; Tadpole larva w dorsal hollow nerve cord, tail, notochord
what are myomeres?
segmented trunk muscles
what are Ascidiacea’s?
Tunicates
what are 3 subgroups of Urochordata?
Ascidiacea, Thaliacea, Appendicularia (Larvacea)
Ascidiacea anatomy
covered by tough tunic; 2 siphons; water pumped into pharynx by oral siphon cilia; endostyle secretes mucus - water passes thru mucus, trapping food; Dorsally, mucus rope moved to esophagus; gas exchange in pharynx
what are the 2 siphons in Ascidiacea?
oral/incurrent, atrial/excurrent
what are the holes in tunicates?
stigmata
Vertebrate synapomorphies:
Distinct head w tripartite brain (fore/mid/hindbrain), cranium (skull); Neural crest; Neurogenic ectodermal placodes;
W-shaped myomeres
what are Thaliacea?
salps, pelagic urochordates that form large colonies
3 major extant subgroups of vertebrates?
lampreys, hagfish, gnathostomes
what are Appendicularia/Larvacea?
larvaceans; Pelagic, retain tadpole-like form as adults; Secrete large mucus “house” for filtering device, protection
what is a Neural crest?
mass of cells lying along neural tube
what are Neurogenic ectodermal placodes?
series of “plates” (thickenings) along neural tube
who were the earliest verts?
Haikouichthys, Myllokunmingia
when did Haikouichthys, Myllokunmingia live?
~530 myo
Haikouichthys, Myllokunmingia characteristics
cranium, heart, W-shaped myomeres, but no bone
what are Cyclostomata?
Agnatha
what groups are in Osteichthyes?
Actinopterygii; Actinistia, Dipnoi; Tetrapoda
What animals are in Cyclostomata?
hagfish, lampreys
what does Gnathostomata mean?
“jaw mouths”
what groups are in Gnathostomata?
Placodermi, Chondrichthyes, Osteichthyes
what are Placodermi?
extinct, heavily armored jawed fish
what are Chondrichthyes?
sharks, skates, rays
what are Actinopterygii?
ray-finned fish
what are Osteichthyes?
Euteleostomi; bony fish, tetrapods
what are Actinistia, Dipnoid?
coelacanths, lungfish
what do Hox genes do?
control segment identity along body (critical in placement and number of limbs, vertebrae)
how many Hox clusters do Cephalochordates have?
1
how many Hox clusters do Hagfish and Lampreys have?
2
how many Hox clusters do Gnathostomes have?
4
what are the neural crest and placodes and what do they do?
Form peripheral nervous system, cranium, adrenal glands, sense organs (nose, eyes, inner ear)
what are Ostracoderms?
paraphyletic group of jawless fish - covered w body carapace or plates, many lack paired fins
what are Conodonts known from?
small, hard comblike “elements”
what are the early Gnathostomes?
Placoderms, Acanthodians
what are placoderms?
armored, large (10 m)
what are acanthodians?
most closely related to Chondrichthyes
what are the living fish?
Cyclostomata, Gnathostomata
What are ”fish”? How would you define them?
aquatic vertebrates w gills, fins, dermal scales; w/o legs
what are Myxini?
hagfish “slime eels”
how many species are there of Myxini?
~70
Myxini characteristics
marine scavenger/predators; Rasp off bits of food w tooth-covered tongue; no scale/vertebrae; fished to make eel skin leather
what are Petromyzontoidea?
lampreys
Petromyzontoidea characteristics
~40, half are blood parasites of fish; No scales, have small cartilaginous vertebral structures; Many spawn in FW – have filter-feeding ammocoete larvae
What is cartilage?
connective tissue made of collagen, elastin
what are the 2 groups of Chondrichthyes?
Holocephali, Elasmobranchii
what are Holocephali?
chimaeras, ratfish; 1 gill opening on head
Elasmobranchii characteristics
multiple gill openings on head; 5-7 gill slit pairs, no swim bladder
what are Elasmobranchii?
sharks, rays
shark characteristics
several groups, predators; placoid scales; include largest “fish”
what are placoid scales?
cellular pulp covered by dentin, enamel
Characteristics of bony fishes include:
Endochondral bone, swim bladder/lungs, most have gills covered w operculum
Rays, skates characteristics
Dorsoventrally flattened, w large pectoral fins; Some w venomous tail barbs
what is an Endochondral bone?
bone that replaces cartilage
what are Osteichthyes?
Clade comprising bony fish and tetrapods; Includes Actinopterygii, Sarcopterygii
what is bone made of?
calcium hydroxylapatite, Ca10(PO4)6(OH)2
Actinopterygii Diversity
Cladistia, Chondrostie, Neopterygii
what are lepidotrichia?
fin rays; Bony, horny spines that support fins
What are Chondrostei?
sturgeons, paddlefish; some bone, mostly cartilage
what are Neopterygii?
all other ray-finned fish
what are Cladistia?
bichirs, reedfish
what groups are in Neopterygii?
Holostei, Telostei
What taxa are in Holostei?
bowfins, gars
What are Actinistia?
2 coelacanth species
what are Apoda?
Gymnophiona, caecilians
what are Teleostei?
possess flexible cycloid or ctenoid scales; have homocercal tail - vertebral column doesn’t extent into tail; bladder buoyancy control w swim bladder (gas-filled esophageal pouch)
what are Dipnoi?
6 lungfish species
what are tetrapods?
animals w 4 feet, legs or leglike appendages; legless groups (snakes) derived from “legged” ancestors
Synapomorphies of Tetrapoda:
Limbs w carpals, tarsals, digits (fingers/toes); Well-developed pectoral, pelvic skeletons; Loss of connection between skull, pectoral girdle (clavicles/scapulae in humans)
what groups are in Lissamphibia?
Caudata, Anura, Apoda
what are the major tetrapod groups?
Lissamphibia, Amniota
Characteristics of sarcopterygian fish
Have central appendage in fins that contains bones, muscles; flexible fins to support body; diphycercal tail
Where do coelacanths and lungfish live?
what are Anura?
frogs, toads
what are Caudata?
Urodela, newts, salamanders
What groups are in Amniota?
Synapsida, Diapsida
what are Synapsida?
mammals, “mammal-like reptiles”
what are Diapsida?
lizards, snakes, dinosaurs, crocodiles, birds, turtles
when did tetrapods arise?
Devonian Period, 380 mya
what is the pulmonary circuit?
deoxygenated blood to lungs and back
what were the environmental conditions during the Devonian Period?
unstable FW habitats, prone to drying out; lungs allowed O2 to be acquired; double circulation in tetrapods arose; pulmonary and systemic circuits
what are some tetrapod relatives (fossils)?
Eusthenopteron, Tiktaalik
Eusthenopteron characteristics
~385 mya; Pectoral girdle attached to skull; Lobe-finned fish w humerus, radius, ulna in anterior fins
Tiktaalik characteristics
~375 mya, sister group to Tetrapoda; Anterior fins w functional wrists, but w fin rays; Flat head that could move independently of shoulders; had neck
what are some tetrapod fossils?
Acanthostega, Ichthyostega
Acanthostega characteristics
~365 mya; no fin rays, 8 digits in forelimb
Ichthyostega characteristics
~365 mya; 7 digits in hindlimb; More robust limbs than Acanthostega (partly terrestrial?)
when were early tetrapods diversified?
Carboniferous period ~354 - 290 mya
what 2 lineages did Tetrapoda give rise to?
Amniota, Temnospondyli
what are Lissamphibia?
Tetrapods w moist, scaleless skin
Lissamphibia characteristics
mucus glands in skin to keep it moist; gas exchange occurs in skin, some have poison glands; 4 limbs, forelimbs w 4 digits; All carnivorous as adults; ear modifications to detect airborne
what amphibians lack digits as adults?
some salamanders, all caecilians
what does Anura mean?
no tail
Apoda characteristics
Gymnophiona; ~180; limbless burrowers in tropics, many blind as adults; have pair of tentacles on head
Anura characteristics
~5000; lack tails as adults; adults specialized for jumping (large hind limbs)
Caudata
~500; Have tails, limbs generally of equal size
what does Gymnophiona mean?
naked snake
Amphibian respiration
aquatic stages have external gills; terrestrial stages have lungs
what is pedomorphosis?
retention of juvenile traits into adulthood; some salamanders become sexually active while retaining gills, aquatic lifestyle
life cycle of amphibians characteristics
metamorphic; aquatic larvae → terrestrial adult; pedomorphosis is common
what is Amniota?
clade that includes “reptiles”, birds, mammals
Mating/fertilization of frogs
males vocalize to attract females; ( aka amplexus), fertilize eggs externally; some brood offspring in male’s vocal pouch or in several small pouches/1 big pouch on females back
what is amplexus?
males clasp females
Synapomorphies of Amniota:
Extraembryonic membranes (chorion, allantois); Amnion, shell support embryo, limit water loss - shell is leathery, calcified; Thick, keratinized skin (limits water loss) – costal (rib) ventilation of lungs
what do extraembryonic membranes in Amniotes do?
allow gas exchange w external environment, waste storage
what is Synapsida (clade)?
mammals, “mammal-like reptiles”
what are the only living temnospondyls?
amphibians
what are Testudines?
(Anapsida) turtles, tortoises
what happens in frog metamorphosis?
aquatic tadpoles grow limbs, absorb tail, develop lungs, absorb gills
what type of development to terrestrial species have?
direct (no larvae)
Mating/fertilization of salamanders
male deposits spermatophore, female picks it up - internal fertilization
Characteristics of Non-Avian Reptiles:
tough, scaly skin + strong jaws; internal fertilization + amniotic egg formation; water conservation (excretion) - secrete uric acid instead of urea/ammonia and salts via salt glands
What do Synapsida, Diapsida and Anapsida refer to?
amount of holes (temporal fenestrae) they have in their skull
how many holes do anapsids have in their skulls?
0
how many holes do Synapsids have in their skulls?
1 pair
how many holes do Diapsids have in their skulls?
2 pairs
what are the scales of non-avian reptiles made of?
hydrophobic lipids, beta keratin
what does oviparous mean?
egg-laying
What do all characteristics of Non-avian reptiles have in common?
beneficial for live in terrestrial (some arid) environments
what extinct groups are in Diapsida (Lepidosauria)?
Ichthyosaurs, Plesiosaurs
what are Lepidosauria?
snakes, lizards
what groups are in Diapsida?
Testudines, Lepidosauria, Archosauria
characteristics of Testudines
body enclosed in dorsal carapace + ventral plastron - vertebral column + ribs fused w carapace; oviparous; after mating, females bury eggs, nest temp determines offspring
what groups are under Lepidosauria?
Sphenodontia, Squamata
what are Sphenodontia?
tuatara are only living members; 1 living species of lizard like animals in New Zealand; parietal eye w lens + retina on head
what are Archosauria?
crocs, dinos, birds
Crocodilia characteristics
23 species; crocs, gaters, caimans, gharials; 4 chambered heart w palatal valve (secondary plate)
what does the palatal valve do in Crocodilia?
keeps water out of throat during diving
what are Squamata?
lizards, snakes, “worm lizards”
what is a kinetic skull?
joints in skull allow snout to be tilted up
Squamata characteristics
kinetic skull
what are the 3 squamate groups?
Amphisbaenia (worm lizards), Sauria (lizards), Serpentes (snakes)
lizard characteristics
~5000; broadly distributed, ecologically diverse; small insectivores to large herbs/carnivores
snake characteristics
~3000; lack pectoral, pelvic girdles, moveable eyelids and external ears; 20% venomous - have pit organs on head to find warm blooded prey
what groups are in Archosauria?
Crocodilia, Dinosauria
Dinosauria major groups
Ornithischia, Saurischia
Synapomorphies of Aves:
Asymmetric wing, tail feathers; forelimbs modified as wings
what animals are in Ornithischia?
Stegosaurus, Triceratops
Similarities of birds and theropod dinosaurs include:
mobile, S-shaped neck; foot w 3 forward toes, 1 backward toe; hollow bones
what animals are in Saurischia?
Sauropods, Tyrannosaurs
What do we call group that includes Paleognathae except tinamous?
ratites
what is an extinct group in Aves?
Archaeopteryx
what are living birds called?
Neornithes
what animals are in Paleognathae?
ostriches, rheas, emus, cassowaries, kiwis, tinamous
feathers are modified scales used for what?
flight, insulation, displays, camo, waterproof
what do feathers consist of?
quill, shaft, barbs, barbules
feathers are usually made of what protein and are in what other things?
beta keratin , found in reptile scales, turtle shells, porcupine quills
what are down feathers for?
insulation
what are contour feathers?
main body feathers, includes remiges and rectrices (wing, tail flight feathers)
characteristics of skeleton and muscles of birds
flight is metabolically demanding - skeleton, muscles, respiration are highly modified
what does pneumatized mean?
filled w air spaces, light but strong
Other skeletal and muscular modifications of birds
no teeth (keratinous beak); most vertebrae, pelvis, pectoral girdle, sternum are fused, large keel on sternum; forelimb bones highly modified
avian respiration characteristcs
tube-like parabronchi in lungs, 9 air sacs
what do parabronchi do?
allow 1 way air flow thru lungs (countercurrent exchange; efficient way to extract oxygen)
circulation characteristics of birds
4-chambered heart
excretion characteristics in birds
excrete nitrogenous wastes as uric acid, better at water conservation than mammals; marine birds secrete salt via salt glands in their head
what is flight good for?
escape from predators, access to food, fast travel; wings provide lift, minimize drage
what do birds use wing slots for?
avoid stalls
what are the types of wings?
elliptical, high-speed, dynamic (active) soaring and high-lift (passive soaring)
what are the 2 forms of slotting?
spaces between primary (wing-tip) feathers; anula (feathers on thumbs)
why do most birds fly south in fall and north in spring?
hard winter conditions, raise young in protective area, reduce comp, lower nest predation
mating characteristics of birds
most monogamous (cheating is common); some polygynous; parental care shared by both parents
what does polygynous mean?
males mate w many females; compete for mates w displys/dances
what is Mammalia the only surviving group of?
Synapsida
what does Mammalia include?
Monotremata, Theria
when did mammals diverge?
~310 mya
What is Monotremata?
egg laying mammals
what groups are in Theria?
Metatheria, Eutheria
what are in Metatheria?
(Marsupialia), marsupials
what are in Eutheria?
(Placentalia), all other mammals (placental)
when were Synapsids dominant on land?
Permian Period, ~290 - 248 mya
what are homodont teeth?
have same shape
what were early synapsids called?
Pelycosaurs (Dimetrodon), had homodont teeth and low metabolic rate
what do the evolution of therapsids/cynodonts show?
erect gait (limbs under body); increased heterodonty; appearance of turbinate bones in nasal cavity; secondary palate
what therapsid group survived Permian-Triassic extinction?
Cynodonta
what does the secondary palate do?
separates nasal passages from mouth
what are hair and fur made of?
alpha keratin
what are synapomorphies of mammals?
hair/fur, diphyodont teeth, sweat (mammary) glands, dentary-squamosal jaw articulation
what are diphyodont teeth?
2 sets of teeth (deciduous and permanent)
what is Dentary-squamosal jaw articulation?
Jaw joint consists of lower jaw bone - dentiary, small bone-squamosal; 2 other jawbones became inner ear bones in mammals
what are the inner ear bones in heterodonts?
incus, quadrate malleus, articular
Characteristics of monotremes
Lay eggs, 1 opening (cloaca) for excretion/reproduction; leathery bill/beak w electrosensory receptors
What structures do male platypuses have on hindlegs?
venomous spurs
Theria characteristics
~300, pouches; short gestation in womb - young climb to pouch to continue growth; largely isolated in Australia 35-50 mya
what are the major groups of marsupials?
Diprotodontia, Dasyuromorphia, Didelphimorphia
what animals are in Diprotodontia?
kangaroos, koalas, wombats
what animals are in Dasyuromorphia?
Tasmanian devil, thylacine
what animals are in Didelphimorphia?
opossums
why are there similar body forms in marsupials and eutherians
convergent evolution
Theria (Eutheria/Placentalia) characteristics
most diverse mammal clade (~4000) - primates, rodents, whales, carnivores; placental mammals - gestation in uterus, nutrients supplied by placenta, young developed at birth
what is hair produced by?
hair follicles
hair characteristics
used for insulation, camo/displays, waterproofing; usually molted 2x year
what are some hair modifications?
vibrissae (whiskers) and porcupine spines
what does the eccrine gland do?
Watery secretion (hairless areas); evaporative cooling
what are the 2 types of sweat glands?
eccrine and apocrine
what does the apocrine gland do?
smelly secretions (armpit/pubic regions); chemical communication
what are the 4 main types of mammal teeth?
…
what do sebaceous glands do?
produce oily sebum; lubricates/waterproofs hair and skin; can produce scents
how did mammal digestive system evolve w diet?
cellulose is hard to digest, micros produce cellulases; some herbivores engage in coprophagy, others are ruminants w 4-chambered heart
what are claws, nails and hooves?
accumulations of keratin on tips of digits
how are horns and antlers used?
male competition and social displays
what are true horns?
keratinized epidermis over bone core
true horns characteristics
only in Bovidae (sheep, antelopes, goats, cattle), not shed after breeding season
