Deuterostomes I: Starfish to Lungfish

Question 1

The synapomorphy of deuterostomes is

Answer 1

deuterstome development

Question 2

2 phyla of deuterstome development

Answer 2

echinodermata and chordata

Question 3

Echinoderms include

Answer 3

starfish and relative (*urchins, sea cucumbers, brittle stars)

Question 4

The synapomorphies of echinoderms are:

Answer 4

1. radial symmetry in adults
2. *water vascular system
3. *endoskeleton made of calcium

Question 5

The 4 chordate synapormorphies are:

Answer 5

1. Notochord
2. Hollow dorsal nerve cord
3. Pharyngeal arches/slits
4. Postanal tail

Question 6

Notochord

Answer 6

• Flexible, cartilaginous rod
• Provides support for basal chordates
• Turns into/gives rise vertebrae during
  development of most vertebrates

Question 7

Hollow dorsal nerve cord:

Answer 7

Develops into brain and spinal cord in
later-diverging chordates

Question 8

Pharyngeal arches/slits

Answer 8

which become
* A filter feeding apparatus in basal
chordates (lancelets and tunicates)
* Gills in aquatic vertebrates
* Cranial/throat features in terrestrial
vertebrates

Question 9

Postanal tail:

Answer 9

• Anus is no longer at the end of the body

Question 10

Chordates appear during

Answer 10

the Cambrian explosion

Question 11

Lancelets (Cephalochordata) are

Answer 11

are the basal/earliest diverging lineage

Question 12

Sister clades of lancelets are

Answer 12

1. Tunicates (Urochordata)
2. Vertebrates (Vertebrata)

Question 13

Lancelets are small, sessile chordates that use _______ for filter feeding on plankton

Answer 13

pharyngeal slits

Question 14

Lancelets are NOT _____ or _____. The have _______ (2) but do NOT have a vertebrate.

Answer 14

fish
vertebrates
notochord and dorsal nerve cord

Question 15

Adult tunicates posses ______ for filter feeding bit NO notochord/nerve cord/post anal tail.

Answer 15

pharyngeal slits

Question 16

Larval tunicates are free-living filter feeders that possess _____

Answer 16

all 4 chordates synapomorphies

Question 17

Molecular phylogenetic show that tunicates are _______

Answer 17

the closest living relatives of vertebrates

Question 18

Vertebrate phylogeny is an ____

Answer 18

evolutionary story

Question 19

What is the evolutionary story?

Answer 19

1. From cartilage to bone
2. from water to land
3. from scales to feathers and to hair
4. from eggs to placenta

Question 20

Synapormophies of vertebrate phylogeny:

Answer 20

Endoskeleton w/ interlocking
cartilaginous vertebrae, Cartilaginous cranium

Question 21

What is an endoskeleton?

Answer 21

internal skeleton for support and
protection

Question 22

Interlocking cartilaginous vertebrae

Answer 22

that replace the notochord

Question 23

Cartilaginous cranium

Answer 23

houses the brain

Question 24

Each of these synapomorphies of vertebrate phylogeny defines

Answer 24

a clade/monophyletic taxon

Question 25

Each MRCA gives those to

Answer 25

two lineages as evolution occurs be speciation

Question 26

Each MRCA gives rise to

Answer 26

a basal lineage and its sister clade

Question 27

Most basal vertebrate lineage

Answer 27

Cyclostomata ("circle mouth")

Question 28

Two sub-clades of cyclostomes/jawless fishes

Answer 28

hagfishes and lampreys

Question 29

Hagfishes are deep sea scavenging fish that are ____. They have _____ but NO ____

Answer 29

super primitive cartilage skull NO vertebrate

Question 30

Loss of vertebrates in cyclostomata is an ____

Answer 30

evolutionary reversal

Question 31

macroevolution doesn’t always give rise

Answer 31

to new features

Question 32

_____ are class of parasitic fish found in fresh and saltwater (sub clade of cyclostomes)

Answer 32

Lampreys

Question 33

Lampreys have NO _____ but they have _____

Answer 33

jaws cartilaginous vertebrae

Question 34

Gnathostomes are

Answer 34

jawed vertebrates

Question 35

The evolution of haws in gnathostomes: Jaws evolved from

Answer 35

gill arches that support gills of fish

Question 36

Chondrichthytes are ____. Examples include:

Answer 36

cartilaginous fishes (ex: sharks, rays)

Question 37

Chondrichthyes posses a

Answer 37

cartilage skeleton (no bone)

Question 38

Shark ancestors had skeletons made of

Answer 38

bones

Question 39

Modern sharks posses but do not express the

Answer 39

genes required to transition cartilage to bone during development

Question 40

Sharks having genes for bones but only having cartilage is an example of

Answer 40

evolutionary reversal because of a mutation that affects spatiotemporal expression (Evo-Devo!)

Question 41

Osteichthyes

Answer 41

"bony fish" - most fish you know + tetrapod descendants

Question 42

The synapomorphy of osteichthyes

Answer 42

Lungs

Question 43

Bones are NOT a synapomorphy of

Answer 43

osteichthyans

Question 44

In Osteichthyes, lungs evolve into _____ in the MRCA of ______.

Answer 44

swim bladders in the MRCA of ray- finned fish

Question 45

What are 2 sub clades of osteichthyes?

Answer 45

1. Ray-finned fishes (Actinopterygii) 2. Lobe-finned fishes and tetrapods (Sarcopterygii)

Question 46

Molecular and morphological phylogenetics suggests _____ evolved first and then evolved into _________

Answer 46

lungs evolved first and then evolved into swim bladders in ray-finned fish

Question 47

zebrafish = danio rerio

Answer 47

simple vertebrate model system used to study development of vertebrates and human diseases

Question 48

Sarcopterygii (3) include:

Answer 48

1. coelacanths 2. lungfishes 3. tetrapods

Question 49

Tetrapods evolved from ____ and redefined to include ______.

Answer 49

ancient lobe-finned fishes tetrapods

Question 50

Lobe finned fishes is a

Answer 50

a paraphyletic taxon that is used when referring to coelacanths and lung fishes

Question 51

2 sister subclasses of Sarcopterygii

Answer 51

* Coelacanths (Actinistia) * Rhipidistia (lungfishes and tetrapods)

Question 52

Coelacanths are considered

Answer 52

living fossils” but the fossil is actually that of its ancestor - it’s just that this lineage has changed little throughout evolutionary history

Question 53

Lungfishes are the only ________ that evolved in the osteicthyan MRCA

Answer 53

only extant fishes that retained the lungs

Question 54

African lungfish bury themselves in mud and

Answer 54

survive for months on dry land until the next rainy season!

Question 55

What are the closest living relatives to tetrapods?

Answer 55

lungfishes are the closest living relatives of tetrapods

Question 56

How lungfishes are the closest living relatives of tetrapods supported by morphological analysis?

Answer 56

1. Lungfish possess four lobed fins that almost look like limbs 2. Lungfish larvae have external gills like the larvae of many amphibians (basal tetrapods)