Unit 5: The Evolutionary History of Diversity
Extras
Study Guide
Chapter 34
Vertebrates
Review
Notes
Point
Vertebrates possess
vertebrae
, and are a
sub-phylum
of
phylum
Chordata
.
Craniates
are chordates that have a
head
and includes
hagfish
.
Vertebrates
are craniates that have a
backbone
, made of
vertebrae
.
Gnathostomes
are vertebrates that have
jaws
that evolved from skeletal supports of the
pharyngeal
slits.
Chondrichthyes
include sharks and rays with a
skeleton
made of
cartilage
.
Osteichthyes
are fish with a
bony
endoskeleton
.
Actinopterygii
are
ray-finned
fishes.
Sarcopterygii
are lobe-finned fishes with more muscular pelvic and pectoral fins and include
coelacanths
and
lungfishes
.
Tetrapods are Gnathostomes that have
four
limbs, and evolved from
lobe-finned
fish whose fins developed into
limbs
adapted for terrestrial life.
Amphibia
undergo
metamorphosis
from aquatic larva into a terrestrial
adult
.
There are
three
orders
:
Urodela
are salamanders,
Anura
are frogs and toads, and
Apoda
are caecilians.
Amniotes
are
tetrapods
that have an
amniotic
egg adapted for terrestrial
life
.
Living
reptiles
include
lizards
,
snakes
,
turtles
,
crocodilians
, and
birds
.
Mammalia
are the only surviving clade of
synapsids
among the amniotes.
Monotremes
are the only mammals that lay
eggs
.
Marsupials
complete embryonic development within a maternal
pouch
called
marsupium
.
Eutherians are
placental
mammals that complete their embryonic development within a
uterus
, joined to the mother by the
placenta.
Anthropoids
are a branch of
primates
and include
monkeys
and
hominoids
called
apes
.
Hominin
are more closely related to humans than to chimpanzees and originated in
Africa
about 6-7 million years ago.
The
Homo
genus
slowly became more fully
bipedal
and evolved a large
brain
.
Summary: Characteristics of chordates