Chordata Flashcards
what are four traits that ALL chordates share
- dorsal hollow nerve cord
- pharyngeal gill slits
- notochord
- post anal tail
outgroup of Chordata
Echinodermata and hemichordate
Chordata includes (10)
- cephalochordates
- urochordates
- agnatha
- chondrichthyan
- Actinopterygii
- sarcopterygii
- amphibia
- reptilia
- aves
- Mammalia
Vertebrata includes
- agnatha
- chondrichthyan
- Actinopterygii
- sarcopterygii
- amphibia
- reptilia
- aves
- Mammalia
tetrapods includes
- amphibia
- reptilia
- aves
- Mammalia
Amniota includes
- reptilia
- aves
- Mammalia
what are the invertebrate chordates
- cephalochordates
- urochordates
least to most inclusive
chordate: Deuterostomia: Bilateria: Eumetazoa: Metazoa
how many animals gave rise to the vertebrates
one
when did the chordates begin to diversify the earth
Cambrian period
symmetry of chordates
bilateral
development of chordates
deuterostome
three clades of chordates
- Cephalochordata
- Urochordata
- Vertebrata
do all chordates show the FOUR derived characters at the same point in their lives
NO - some have them in the larval phase and others the adult phase
notochord
a longitudinal, flexible rod between digestive tube and nerve cord
what kinds of support is given by the notochord
skeletal and muscular support
where do we see the notochord in vertebrates
remnants remain at adulthood
how does the dorsal, hollow nerve cord develop
from a plate of ectoderm
what does the dorsal hollow nerve cord develop into
CNS (brain and spinal cord)
pharyngeal clefts
develop into the slits that open outside of the body
function of pharyngeal slits in invertebrate chordates
suspension-feeding structures
function of pharyngeal slits in vertebrates (EXCEPT those with limbs= tetrapods)
gas exchange
pharyngeal slits in tetrapods develop into
parts of the ear, head and neck
describe the post-anal tail in many species
highly reduced during embryonic development
what does the post-anal tail contain
skeletal elements and muscles
what does the post-anal tail provide for aquatic species
propelling force
Cephalochordata are
lancelets
least to most inclusive
Lancelets: Cephalochordata: Chordata: Deuterstomia: Bilateria: Eumetazoa: Metazoa
Cephalochordata are named for their
blade-like shape
habitat of Cephalochordata
marine
where do Cephalochordata retain the characteristics of the chordate body
adults
Urochordata are
tunicates aka sea squirts
Urochordata are most closely related to _____ than _____
other chordates then lancelets
least to most inclusive
Tunicates: Urochordata: Chordata: Deuterostomia: Bilateria: Eumetazoa: Metazoa
describe different kinds of Urochordata and their lifestyles
- most are sessile
- some are planktonic
- some are solitary
- some are colonial
reproduction in Urochordata
hermaphroditic with broadcast spawning
when does the Urochordata show the chordate body characters
in the larval stage
what makes Urochordata highly diverged
they have fewer hox genes
their chordate body characters are in the larva stage
explain how chordates could resemble lancelets
the Hox genes in the vertebrate brain are expressed in the lancelets simple never cord
what do Hox genes control
- cephalization (anterior vs posterior)
- control the development of paired appendages
vertebrates are more closely related to _______ (Cephalocordata or Urochordata)
Urochordata
what are three things that the sequencing of the tunicate gnome suggests
- genes associated with the heart and thyroid are common to ALL chordates
- genes associated with the transmission of nerve impulses UNIQUE to vertebrates
- neural crest
what is more accurate:
vertebrates are chordates that have a backbone
OR
vertebrates are chordates that have a vertebrae
vertebrates are chordates that have a verterbrae
what has allowed vertebrates to become more efficient at
1. capturing food
2. evading predators
- skeletal system
- complex nervous system
describe the Hox genes in the verberates
two sets of Hox genes (4 sets of Hox genes)
Hox genes of lancelets and tunicates VS the other vertebrates
have only ONE cluster of Hox genes
what are the derived characteristics of vertebrates
- vertebrae enclosing a spinal cord
- an elaborate skull
- fin rays (aquatic forms)
where do neural crest cells appear
along the edges of the closing neural tube of an embryo
what do neural crest cells give rise to
- teeth
- some bones
3.cartilage of the skull - several types of neurons and sensory capsules
how did animals of vertebrates get their name
from vertebrae (series of bones that make up the backbone)
what are the closest living relatives to cetaceans (whales and dolphins)
vertebrates that MOVED to the water after being on land
four innovations of early vertebrates
- cranium
- vertebrae
- bone
- neural crest cells
order these traits from OLDEST to NEWEST in the evolution history
1. limbs capable of moving on land
2. amniotic eggs
3. bony exoskeleton
5. bony endoskeleton
6. jaws
- bony exoskeleton
- jaws
- bony endoskeleton
- limbs capable of moving on land
- amniotic eggs
Haikouella place in the evolution of vertebrates
a fossil that LACKED a cranium
myllokunmingia’s place in the evolution of vertebrates
First vertebrate WITH a cranium
importance of Conodonts
they were the fossilized vertebrate that LACKED a jaw but HAD mineralized skeletal elements in their mouth and pharynx
did the earliest vertebrates lack or have jaws
lacked jaws
two lineages of jawless vertebrates
- hagfishes
- lampreys
clade of jawless vertebrates are the
cyclostomes
vertebrates with jaws make up the clade
gnathostomes
Myixni are the
hagfishes
least to most inclusive
Hagfish: Myxini: Cyclostomes: Vertebrata: Chordata: Deuterostomata: Bilateria: Eumetazoa: Metazoa
least to most inclusive
lampreys: Petromyzontida: Cyclostomes: Vertebrata: Chordata: Deuterostomata: Bilateria: Eumetazoa: Metazoa
least to most inclusive
Chondrichthyes: Gnathostomes: Vertebrata: Chordata: Deuterostomata: Bilateria: Eumetazoa: Metazoa
where do Myxini live
marine
Petromyzontida are _______ (way of feeding_
parasites
habitat of Petromyzontida
marine and freshwater
Gnathostomes include
- sharks
- ray-finned fishes
- lobe-finned fishes
- amphibians
- reptiles
- birds
- mammals
what are Gnathostome jaws hypothesized to evolve from
skeletal supports of the pharyngeal (gill) slits
describe the evolution of the function of the Gnathostome jaw
it went from feeding to respiration
what are traits that Gnathsotomes have that Cyclostoms LACK
- another gene duplication
- enlarged forebrain for enhanced smell and vision
- lateral line system (aquatic species)
why are cyclostomes NOT predators
because the development of predators require ANOTHER gene duplication
basal lineage of Gnathostomes
Chondrichthyes
lateral line system
a sensory system found in fishes and aquatic amphibians
what are unique to Chondrichthyes
chondrocytes (cells that make cartilage)
are the presence of chondrocytes in Chondrichthyes a plesiomorphic or apomorphic condition
apomorphic (derived)
three types of birthing “methods” found in Chondrichthyes
- oviparous
- ovoviviparous
- viviparous
what type of Chondrichthyes birth is this
lays eggs
oviparous
what type of Chondrichthyes birth is this
the eggs hatch internally
ovoviviparous
what type of Chondrichthyes birth is this
lay live young
viviparous
a vast number of vertebrates belong to what SPECIFIC clade in Gnathsotomes
Osteichthyes
what are the Bony Fishes
- Actinopterygii
- Actinistia
- Dipnoi
out of the bony fish, which is/are the Ray-Finned fish
Actinopterygii
out of the bony fish, which are/is the lobe-finned fish
- Actinisitia
- Dipnoi
what are the lobe-finned fish called
Sacroptyergii
Historic Osteichthyes are also known as
the bony fish (all three lineages of the bony fish)
what lineages are considered to be under the Ostiechithyes
- bony fish (Actinosptyerygii, Actinistia, Dipnoi)
- Tetrapods (Amphibia, Reptilia, Mammalia)
what lineage of bony fish is SISTER to us (humans/mammals)
Sacropterygii
what do all living Osteichthyans share
a bony endoskeleton
what sets tetrapods apart from other gnathostomes
they have limbs WITH digits
what are some adaptions seen in tetrapods
- four limbs with digits
- neck that separates movement of the head
- fusion of pelvic girdle to backbone
- absence of gills (besides some aquatic species)
- ears for detecting sounds
what was a transitional species of BOTH the fishes and tetrapods
tiktaalik
tiktaalik
least to most inclusive
ray-finned fish: Actinopterygii: Osteichthyes: Vertebrata: Chordata: Deuterstomia: Bilateria: Eumetazoa: Metazoa
least to most inclusive
Actinistia: Sarcopterygii: Osteichthyes Vertebrata: Chordata: Deuterstomia: Bilateria: Eumetazoa: Metazoa
least to most inclusive
Dipnoi: Sarcopterygii: Osteichthyes: Vertebrata: Chordata: Deuterostomia: Bilateria: Eumetazoa: Metazoa
what traits of FISH did Tiktaalik show
- scales
- fins
- gills and lungs
what traits of TETRAPODS did Tiktaalik show
- neck
- ribs
- fin skeleton
- flat skull
- eyes on top of the skull
three clades of Amphibians
- frogs
- salamanders (Urodela)
- Caecilians
least to most inclusive
salamander: order Urodela: Amphibians: vertebrata: Chordata: Deuterostomia: Bilateria: Eumetazoa: Metazoa
what does it means when salamanders show paedomorphosis
their ability to retain juvenile features in sexually mature organisms
are Amphibians tied to water
YES
least to most inclusive
frogs: Order Anura: Amphibians: Vertebrata: Chordata: Deuterstomia: Bilateria: Eumetazoa: Metazoa
how to tell a frog from a toad
toads have more leathery skin
least to most inclusive
Caecilians: Apoda: Amphibians: Vertebrata: Chordata: Deuterostomia: Bilateria: Eumetazoa: Metazoa
what kind of adaption is the absence of legs in Caecilians
secondary adaption
fertilization of amphibians is
external
Amniotes are a group of _______ whose members have a ______
tetrapods AND have extra membranes around their developing embryo
2 lineages of Amniotes
- Diapsids
- Synapsids
what lineage of Amniotes gave rise to the birds AND dinosaurs
- Diapsids
what lineage of Amniotes gave rise to the mammals
Synapsids
what are the FOUR extra layers that make up the amniotic egg
- allantois
- chorion
- amnion
- yolk sac
what kind of membranes are the amniotic eggs
EXTRAembryonic
least to most inclusive
amniotes: Vertebrata: Chordata: Deuterostomia: Bilateria: Eumetazoa: Metazoa