Kingdom Animalia
(non-chordates)
• What is a non-chordate?
• Lacks a notochord
• In LARGE part this is synonymous with
invertebrate
• ALL non-chordates are invertebrates
• BUT not all invertebrates are nonchordates
Phylum Placozoa
• Trichoplax adhaerens looks a bit like a
flattened blastula
• Now generally considered in the Eumetazoa
• 3 layers (?)
– Dorsal epithelioid layer
– Syncytial layer (loose, much fluid)
– Ventral epithelioid layer
• Originally thought to be a larval stage of an
animal
Trichoplax adhaerens
Phylum Porifera (?)
• Two Phyla of sponges (?)
(Calcarea & Silicea)
• Suspension (filter) feeders (porocytes)
• Very loose organization of cells
• Choanocytes and Amoebocytes
• Spicules
• Sexual and asexual reproduction
• Hermaphroditic (= monoecious = bisexual)
A “Typical” Sponge
Fig. 33-4
Choanocyte
Osculum
Flagellum
Collar
Food particles
in mucus
Choanocyte
Azure vase sponge (Callyspongia
plicifera)
Spongocoel
Phagocytosis of
food particles
Pore
Epidermis
Spicules
Water
flow
Amoebocytes
Mesohyl
Amoebocyte
Phylum Cnidaria
Table 33-1
Phylum Cnidaria
•
•
•
•
•
Tissues
Muscles in their simplest form
Simple nerve net
Cnidocytes
Two body plans
– Polyp
– Medusa
• Dioecious (= unisexual)
• Gastrovascular Cavity (only one opening)
Phylum Cnidaria (Body Plans)
Fig. 33-5
Mouth/anus
Polyp
Tentacle
Medusa
Gastrovascular
cavity
Gastrodermis
Body
stalk
Mesoglea
Epidermis
Tentacle
Mouth/anus
Hydra sp.
Phylum Cnidaria
Fig. 33-6
Tentacle
Cuticle
of prey
Thread
Nematocyst
“Trigger”
Thread
discharges
Cnidocyte
Thread
(coiled)
Phylum Ctenophora
•
•
•
•
The Comb Jellies
Somewhat medusa-like
Monoecious
One species has cnidocytes
Phylum Platyhelminthes
•
•
•
•
Bilateria
Triploblastic
Acoelomate
Protostomes
Phylum Platyhelminthes
Table 33-2
Class Turbellaria
•
•
•
•
•
•
•
•
Flatworms
Free living
Carnivores
How do they move? Feed?
Rudimentary brain
Two ventrolateral nerve cords
Hermaphroditic (but cross fertilizing)
Can reproduce asexually
Class Turbellaria
Planaria sp.
Fig. 33-10
Pharynx
Gastrovascular
cavity
Mouth
Eyespots
Ganglia
Ventral nerve cords
Class Trematoda
•
•
•
•
Flukes
Dioecious
Parasitic
Life cycles often complex
– May alternate between asexual & sexual cycles
– Alternate between two or more hosts
Class Trematoda
Blood Fluke
(Schistosoma mansoni)
Fig. 33.11
Male
Female
Human host
1 mm
Motile larva
Ciliated larva
Snail host
Class Cestoidea
•
•
•
•
Tapeworms
Parasites
No digestive tract
Monoecious but usually cross fertilize
Class Cestoidea
Fig. 33-12
200 µm
Proglottids with
reproductive structures
Hooks
Sucker
Scolex
Taenia solium Life Cycle
Phylum Nemertea
• Ribbon or proboscis worms
• Simple circulatory system with RBCs
• Complete digestive system
(2 openings)
• Protostomes
• Acoelomate ?
• Usually dioecious
Phylum Nemertea
Phylum Rotifera
•
•
•
•
•
•
Rotifers (sometimes called “wheel” animals)
Protostomes
Dioecious
Often PARTHENOGENETIC
Sometimes have “degenerate” males
NO regeneration capabilities (fixed number
of cells; fate maps)
Phylum Rotifera
Phylum Mollusca
Table 33-3
Phylum Mollusca
•
•
•
•
•
•
•
Eucolomate
Protostomes
Most dioecious & most reproduce sexually
Open circulatory system except cephalopods
Body: foot, visceral mass, mantle
Cephalization variable
Varied feeding modes
Circulatory Systems
Molluscan Evolution
Class Polyplacophora
• 8 covering plates
• Radula
Fig. 33-16
Class Gastropoda (Snails & Slugs)
•
•
•
•
•
Most have a radula
One-piece shell or shell absent
Cephalization variable
Muscular foot for locomotion
Torsion
Typical Snail
Fig. 33-18
Mantle
cavity
Anus
Mouth
Stomach
Intestine
Class Bivalvia (= Pelycopoda)
•
•
•
•
All the two-shelled forms
Shells (valves) are RIGHT & LEFT
Economically important group
Filter feeders
Clam
Fig. 33-20
Mantle
Hinge area
Coelom
Gut
Heart Adductor
muscle
Digestive
gland
Anus
Mouth
Excurrent
siphon
Shell
Palp
Foot
Mantle
cavity
Gonad
Gill
Water
flow
Incurrent
siphon
Class Cephalopoda
• Ammonite – one extant species (chambered
nautilus) --- shell present
• Squid --- shell greatly reduced and internal
• Octopus --- shell absent
• Closed circulatory system
• Well developed brain and sense organs
• Agile carnivores
Class Cephalopoda
Fig. 33-21
Octopus
Squid
Chambered
nautilus
Phylum Annelida
Table 33-4
Phylum Annelida
•
•
•
•
•
•
•
•
Eucoelomates
Protostomes
Closed Circulatory system
Segmented body
Coelom partitioned by septa (sing. septum)
Monoecious but cross fertilizing
Rudimentary brain; fused ventral nerve cords
Hydrostatic skeleton (read about movement)
Class Oligochaeta
Fig. 33-22
Epidermis
Cuticle
Coelom
Circular
muscle
Septum
(partition
between
segments)
Metanephridium
Longitudinal
muscle
Anus
Dorsal vessel
Chaetae
Intestine
Fused
nerve
cords
Ventral
vessel
Nephrostome
Metanephridium
Clitellum
Esophagus
Crop
Pharynx
Giant Australian earthworm
Intestine
Gizzard
Cerebral ganglia
Mouth
Subpharyngeal
ganglion
Blood
vessels
Ventral nerve cord with
segmental ganglia
Class Polychaeta
Class Hirudinea
Fig. 33-24
Phylum Nematoda
•
•
•
•
•
•
Roundworms
Pseudocoelomates
Protostomes
Only longitudinal muscles
Dioecious
Like rotifers they have a fixed number of
cells
Phylum Nematoda
• Some are important plant or animal
parasites or experimental organisms
• Chaenorabditis elegans
• Trichinella spiralis (poorly cooked pork)
• Important decomposers and nutrient
recyclers
Phylum Nematoda
Phylum Arthropoda
Table 33-5
CHARACTERISTICS
•
•
•
•
•
•
•
Jointed appendages
Exoskeleton of chitin
Molting
Extensive cephalization
Open circulatory system
Diverse respiratory structures
Diverse feeding methods
WHY SO SUCCESSFUL ?
•
•
•
•
Have an important PREADAPTATION
Segmented body and jointed appendages
Generally have smaller size
Generally have a shorter life cycle
WHY SO IMPORTANT ?
•
•
•
•
•
•
•
Foods
Disease spread
Pollination
Poisonous and/or irritating
Crop and building destruction
Scary ???
Other ???
Phylum Arthropoda
Subphylum Cheliceriformes
• Possess chelicerae
• No antennae
• Body usually of two parts
– Cephalothorax
– Abdomen
• Spiders have 8 legs
Subphylum Myriapoda
• Many segmented bodies
• Have antennae
• Class Chilopoda
– Centipedes – carnivores (venomous)
• Class Diplopoda
– Millipedes – usually debris feeders (2 pairs of
legs per apparent body segment)
Subphylum Crustacea
•
•
•
•
Body of two or three parts
Two pair of antennae
Mostly marine
Important foods
Subphylum Hexapoda
• Formerly Class Insecta
• 3 body areas
– Head
– Thorax --- with 3 pairs of legs and often with
two pairs of wings
– Abdomen
• One pair of antennae
• Compound eyes usually present
• Importance of Insects
Grasshopper –Typical Insect
Insect Evolution
Insect Metamorphosis
PHYLUM ECHINODERMATA
Echinoderm Traits
•
•
•
•
•
•
•
Radially symmetrical as adults
These are in the bilateria. WHY???
BILATERALLY symmetrical as larvae
Most closely related phylum to the Chordata
Some have regeneration ability
Exoskeleton Or Endoskeleton ???
Water vascular system (complete or
incomplete)
• Importance
Water Vascular System
Echinoderms