Kingdom AnimaliaDeuterostome

Animals

Remember the 4 deteurostome development characteristics

2 worm-like groups near the base of this part of the tree (2/11):

Acoelamorphs Xenoturbellids

P: Echinodermata = “spiny-skinned”

Echinoderm anatomy

Water vascular system

Another C: “sea daisies”

P: Hemichordata = acorn worms & pterobranchs

somites

Important chordate characteristics

SP: Urochordata = tunicates

sea squirts (ascidians), salps, appendicularians

adult

larva

SP: Cephalochordata = lancelets

tentaclesPikaia(Wikipedia)

Hox gene clusters

Fig 17-13

Craniates

distinctive head (skull, brain, sense organs)

active predators

duplicated Hox genes

Craniate features (cont.)

new neural crest tissue

more complex organs

Haikouella (fossil; Wikipedia)

Fig 51-11

SP:

Early vertebrates

agnathans

Haikouichthyes (Wikipedia)

conodonts

ostracoderms (Wikipedia)

C: Myxini = hagfishes

C: Petromyzontidae (Cephalaspidomorpha) = lampreys

Gnathostomes = jawed mouths

Jaw evolution

Gnathostomes

more gene duplication

forebrain larger

lateral line

mineralization

C: Chondrichthyes = cartilaginous fish

Clade Osteichthyes

C: Actinopterygii = ray-fin fishes

Garibaldi (CA marine fish)

C: Actinistia = coelocanth

C: Dipnoi = lungfish

Clade Sarcopterygii

Early Tetrapods

(many of these added in the last 20 years)

(Wikipedia)

Tetrapods

C: AmphibiaO: Anura = frogs & toads

O: Apoda = caecilians

O: Urodela = newts & salamanders

Ichthyostega

Clade Amniotes

Amniotic egg

C: Reptilia

C: Reptilia

Birds

Adaptations for flight

C: Mammals

Protherians = Monotremes = egg-layers

spiny echidna

C: Mammals

Metatherians = Marsupials = pouched mammals

C: Mammals

Eutherians = placental mammals

Convergent evolution