TOPIC 7
ANIMAL DIVERSITY
I. CHARACTERISTICS OF KINGDOM ANIMALIA
II. OVERVIEW OF ORIGINS & DIVERSITY
III. BODY PLANS & RELATIONSHIPS
A. PRESENCE OF TISSUES
B. BODY SYMMETRY
C. DEVELOPMENTAL PATTERNS &GERM LAYERS
D. PRESENCE & NATURE OF COELOM (BODY CAVITY)
IV. CHORDATE EVOLUTION
A. INVERTEBRATE CHORDATES
B. VERTEBRATES: ORIGINS OF MAJOR FEATURES
I. CHARACTERISTICS OF KINGDOM
A. MULTICELLULAR, DIPLOID ORGANISMS
B. HETEROTROPHS THAT FEED VIA INGESTION
C. NO CELL WALLS
D. STORE ENERGY AS GLYCOGEN
E. COLLAGEN
F. DISTINCTIVE INTERCELLULAR CONNECTIONS
G. EXCITABLE TISSUES
9 MAJOR ANIMAL PHYLA
PORIFERA: SPONGES
9,000 species
CNIDARIA: JELLYFISH, CORAL, ANEMONES
10,000 species
PLATYHELMINTHES: FLATWORMS, FLUKES, TAPEWORMS
20,000 species
NEMATODA: ROUNDWORMS
100,000 species
MOLLUSCA: SNAILS, CLAMS, SQUIDS
50,000 species
ANNELIDA: SEMENTED WORMS
15,000 species
ARTHROPODA: INSECTS, ARACHNIDS, CRUSTACEANS
1,000,000 species
ECHINODERMATA: SEA STARS, URCHINS, CUCUMBERS
7,000 species
CHORDATA: TUNICATES, LANCLETS, VERTEBRATES
40,000 species
(PLUS 25 TO 28 MINOR PHYLA)
III. BODY PLANS
A. PRESENCE OF TISSUES
1. TRUE TISSUE PRESENT:
EUMETAZOA
2. TRUE TISSUE ABSENT:
PARAZOA
= CELLULAR GRADE OF ORGANIZATION
PHYLUM PORIFERA
CHOANOCYTE CELLS
POROCYTE CELLS
AMOEBOCYTE CELLS
FILTER FEEDERS
INTERNAL "SKELETON" OFSPICULES OR FIBERS
(Si, Ca, or Proteins)
III. BODY PLANS
B. BODY SYMMETRY
1. RADIAL SYMMETRY: RADIATA
ORAL & ABORAL SURFACE
( = TOP & BOTTOM)
WHEEL - LIKE
USUALLY PLANKTONIC OR SESSILE
PHYLUM CNIDARIA
2. BILATERAL SYMMERTY: BILATERIA
DORSAL & VENTRAL SURFACE
( = TOP & BOTTOM)
LEFT & RIGHT
ANTERIOR & POSTERIOR END
CEPHALIZATION
USUALLY ACTIVE
REMAINING EUMETAZOA
III. BODY PLANS
C. DEVELOPMENT & GERM LAYERS
1. EMBRYO DEVELOPMENT
a. BLASTULA
HOLLOW BALL OF CELLS
b. GASTRULA
TWO-LAYERED, CUP-SHAPED EMBRYO
FORMED VIA GASTRULATION
INWARD MIGRATION OF CELLS
RESULTS IN 2 GERM LAYERS
c. ECTODERM
OUTER GERM LAYER
GENERALLY GIVES RISE TO "SKIN"
CAN GIVE RISE TO NERVOUS SYSTEM
d. ENDODERM
INNER GERM LAYER
LINES ARCHENTERON
= EMBRYONIC GUT
GIVES RISE TO DIGESTIVE TRACT
GIVES RISE TO ASSOCIATED ORGANS
LUNGS
LIVER & PANCREAS
III. BODY PLANS
C. DEVELOPMENT & GERM LAYERS
2. DIPLOBLASTIC ORGANISMS
2 BODY LAYERS
OUTER = EPIDERMIS
INNER = GASTRODERMIS
GUT = BLIND SAC
= GASTROVASCULAR CAVITY
RADIATA
3. TRIPLOBALSTIC ORGANISMS
3 GERM LAYERS
MESODERM = MIDDLE LAYER
GIVES RISE TO MUSCLE
ENDOSKELETON
CIRCULATORY SYSTEM
EXCRETORY ORGANS
BILATERIA
RADIATA
PHYLUM CNIDARIA
PHYLUM CTENOPHORA (COMB JELLIES)
FEATURES OF CNIDARIANS:
SINGLE GUT OPENING ENCIRCLED BY TENTACLES
MIDDLE ACELLULAR LAYER OF MESOGLEA
UNIQUE CELLS FOR FEEDING & DEFENSE
= CNIDOCYTES
MOVE USING CONTRACTILE FILAMENTS & A HYDROSTATIC SKELETON
POLYP (HYDROID) & MEDUSA (JELLYFISH) FORMS
3 CLASSES
HYDROZOA (ALTERNATE FORMS)
SCYPHOZOA (MAINLY MEDUSA)
ANTHOZOA (POLYP ONLY)
SOLITARY OR COLONIAL
MARINE OR FRESHWATER
III. BODY PLANS
D. PRESENCE & NATURE OF COELOM
1. COELOM
ENCLOSED BODY CAVITY
FLUID FILLED
BETWEEN GUT & BODY WALL
2. ACOELOMATES
MESODERM PRESENT
BODY CAVITY ABSENT
3. PSEUDOCOELOMATES
MESODERM PRESENT
BODY CAVITY PRESENT
BODY CAVITY NOT COMPLETELY LINED WITH MESODERM
4. [EU]COELOMATES
MESODERM PRESENT
BODY CAVITY PRESENT
BODY CAVITY LINED INSIDE & OUT WITH MESODERM
ACOELOMATES
PHYLUM PLATYHELMINTHES
BLIND GASTROVASCULAR CAVITY
DIVERSE MESODERMAL STRUCTURES
EXTENSIVE MUSCLE SYSTEM
SOLID BODY ACTS AS HYDROSTATIC SKELETON
PRIMITIVE EXCRETORY SYSTEM
LACK RESPIRATORY STRUCTURES
HERMAPHRODITES
4 CLASSES INCLUDE
TURBELLARIA
: FREE-LIVINGEXAMPLE = PLANARIANS
TREMATODA:
PARASITIC FLUKESCESTODA:
PARASITIC TAPEWORMS
PSEUDOCOELOMATES
PHYLUM NEMOTODA
PHYLUM ROTIFERA
3+ OTHER PHYLA
FEATURES OF NEMATODES
PSEUDOCOELOM USED AS HYDROSTATIC SKELETON
RIGID EXTERNAL CUTICLE
LONGITUDINAL MUSCLES ONLY
PSEUDOCOELOM USED FOR CIRCULATION
COMPLETE GUT
(MOUTH & ANUS)
SEPARATE SEXES
FREE-LIVING IN SOIL & SEDIMENTS
PARASITES OF PLANTS & ANIMALS
III. BODY PLANS
D. PRESENCE & NATURE OF COELOM
2 KINDS OF TRUE COELOMS
1. SCHIZOCOELOM
FORMS IN THE EMBRYO VIA SPLITTING OF A SOLID MASS OF MESODERM
FOUND IN PROTOSTOMES
2. ENTEROCOELOM
FORMS IN THE EMBRYO VIA OUTPOUCHING OF THE GUT
FOUND IN DEUTEROSTOMES
PROTOSTOMES
1. SPIRAL & DETERMINATE CLEAVAGE IN EMBRYO
2. MOUTH DEVELOPS FROM BLASTOPORE OF GASTRULA
3. SCHIZOCOELOUS BODY CAVITY
4. VENTRAL NERVE CORD
PHYLUM MOLLUSCA
PHYLUM ANNELIDA
PHYLUM ARTHROPODA
5+ MINOR PHYLA
DEUTEROSTOMES
1. RADIAL & INDETERMINATE CLEAVAGE IN EMBRYO
2. ANUS DEVELOPS FROM BLASTOPORE OF GASTRULA
3. ENTEROCOELOUS BODY CAVITY
4. DORSAL NERVE CORD
PHYLUM ECHINODERMATA
PHYLUM CHORDATA
2 MINOR PHYLA
PROTOSTOMES
PHYLUM MOLLUSCA
CHARACTERISTICSBODY UNSEGEMENTED
3 MAJOR BODY REGIONS
1. FOOT = LOCOMOTION
2. VISCERAL MASS = ORGANS
3. MANTLE = DORSAL TISSUE
SECRETES SHELL
ORIGINATED AS CREEPING, SCRAPING HERBIVORE WITH A RADULA
4 MAJOR CLASSES
POLYPLACOPHORA = CHITONS
GASTROPODA = SNAILS & SLUGS
BIVALVIA = CLAMS, OYSTERS, MUSSELS, SCALLOPS
CEPHALOPODA = SQUIDS, OCTOPUSES, NAUTILUS
PROTOSTOMES
PHYLUM ANNELIDA
CHARACTERISTICSBODY SEGEMENTED
REPEATED UNITS = METAMERES
USED AS HYDROSTATIC SKELETON FOR PERISTALTIC MOVEMENT
3 CLASSES
OLIGOCHAETA
= "FEW SETAE"TERRESTRIAL & FRESHWATER
POLYCHAETA
= "MANY SETAE"MARINE, BEAR PARAPODIA
HIRUDINEA
= LEECHESLACK SETAE, FRESHWATER
PROTOSTOMES
PHYLUM ARTHROPODA
CHARACTERISTICSBODY SEGEMENTED
SEGMENTS FORM FUNCTIONAL UNITS = TAGMATA
JOINTED APPENDAGES
SPECIALIZED IN FORM & FUNCTION
EXOSKELETON OF CHITIN
STRONG
FLEXIBLE
WATERPROOF
5 MAJOR CLASSES
ARACHNIDA = SPIDERS, SCORPIONS, MITES, TICKS
BODY UNITS = 1 OR 2 TAGMATA
MOUTH PARTS = CHELICERAE
4 PAIRS WALKING LEGS
LACK ANTENNAE
MAINLY TERRESTRIAL
DIPLOPODA = MILLIPEDES
HEAD PLUS MANY UNSPECIALIZED BODY UNITS
MOUTH PARTS = MANDIBLES
MANY WALKING LEGS (2 / SEGMENT)
1 PAIR ANTENNAE
TERRESTRIAL
CHILOPODA = CENTIPEDES
HEAD PLUS MANY UNSPECIALIZED BODY UNITS
MOUTH PARTS = MANDIBLES
MANY WALKING LEGS (1 / SEGMENT)
1 PAIR ANTENNAE
TERRESTRIAL
INSECTA = INSECTS
BODY UNITS = 3 TAGMATA
MOUTH PARTS = BASIC MANDIBLES OR MODIFIED FOR SUCKING, ETC.
3 PAIRS WALKING LEGS
1 PAIR ANTENNAE
WINGS ARE WIDESPREAD
TERRESTRIAL & FRESHWATER
CRUSTACEA = DECAPODS, COPEPODS, ISOPODS, AMPHIPODS, OSTRACODS, BARNACLES, CLADOCERANS
BODY UNITS = 2- 3 TAGMATA
MOUTH PARTS = MANDIBLES
3 OR MORE PAIRS OF LEGS
2 PAIRS OF ANTENNAE
MAINLY MARINE & FRESHWATER
PROTOSTOMES OR DEUTEROSTOMES?
LOPHORATE ANIMALS
3 PHYLA
5500 species
COLONIAL BRYOZOANS
PHORONID WORMS
BIVALVE-LIKE BRACHIOPODS
UNITED BY PRESENCE OF LOPHOPHORE ORGAN
= FEEDING STRUCTURE BEARING CILIATED TENTACLES
DEUTEROSTOMES
PHYLUM ECHINODERMATA
UNSEGMENTED
ANCESTORAL BILATERAL SYMMETRY REFLECTED IN LARVAE
SECONDARY RADIAL SYMMETRY IN ADULTS => FILTER FEEDERS
IN SOME BURROWING FORMS, ADULTS RETURNED TO BILATERAL SYMMETRY
UNIQUE WATER VASCULAR SYSTEM
= FLUID FILLED CANALS ENDING IN MUSCULAR TUBE FEET
USED IN FEEDING, GAS EXCHANGE & LOCOMOTION
ENDOSKELETON = PLATES OF CALCIUM CARBONATE
5 CLASSES (ALL MARINE)
CRINOIDEA = SEA LILIES
ASTEROIDEA = SEA STARS
OPHIUROIDEA = BRITTLE STARS
ECHINOIDEA = SEA URCHINS
HOLOTHUROIDEA = SEA CUCUMBERS
DEUTEROSTOMES
PHYLUM CHORDATA
4 MAJOR FEATURES OCCUR IN ALL CHORDATES AT SOME PHASE OF THE LIFE CYCLE
1. NOTOCHORD
1ST AXIAL ENDOSKELETON
DORSAL FLEXIBLE ROD
LOCOMOTION
2. DORSAL HOLLOW NERVE CORD
INFOLDING OF ECTODERM
PRECURSOR OF BRAIN & SPINAL CORD
COORDINATION
3. PHARYNGEAL SLITS
LATERAL OPENINGS IN THE FOREGUT
SUPPORTED BY CONNECTIVE TISSUE (ARCHES)
1ST FOR FILTER FEEDING, LATER FOR RESPIRATION
4. MUSCULAR POSTANAL TAIL
POSTERIOR EXTENSION OF NOTOCHORD & MUSCLE SEGMENTS
LOCOMOTION
DEUTEROSTOMES
PHYLUM CHORDATA
SUBPHYLUM UROCHORDATA
TUNICATES, SALPS, SEA SQUIRTS
MARINE
ADULTS SESSILE OR PLANKTONIC
FILTER FEEDERS WITH PHARYNGEAL BASKET
ACTIVE "TADPOLE" LARVAE DISPLAY CLASSIC CHORDATE FEATURES
LARVAE MAY HAVE GIVEN RISE TO OTHER CHORDATES THRU PAEDOGENESIS
DEUTEROSTOMES
PHYLUM CHORDATA
SUBPHYLUM CEPHALOCHORDATA
LANCELETS
MARINE
FILTER FEEDERS
BURROW IN SUBSTRATE
DISPLAY CLASSIC CHORDATE FEATURES IN ADULTS
NOTOCHORD EXTENDS INTO HEAD
DEUTEROSTOMES
PHYLUM CHORDATA
SUBPHYLUM VERTEBRATA
VERTEBRATES
APPEAR 520 mybp = MARINE
CLASSIC CHORDATE FEATURES SEEN ONLY IN EMBRYOS OF MANY SPECIES
CHARACTERIZED BY:
3-PART BRAIN
NEURAL CREST CELLS
CRANIUM (BRAIN CASE)
ENDOSKELETON OF BONE
VERTEBRAE (REPLACE NOTOCHORD)
MAJOR EVENTS IN VERTEBRATE EVOLUTION
520 mybp
1st KNOWN VERTEBRATES
= AGNATHA
460 mybp
EVOLUTION OF JAWS FROM ANTERIOR PHARYNGEAL ARCH = GNATHOSTOMATA
EVOLUTION OF PAIRED FINS
CHONDRICHTHYES
OSTEICHTHYES
RAY-FINNED FISHES
FLESHY-FINNED FISHES
MAJOR EVENTS IN VERTEBRATE EVOLUTION
360 mybp
INVASION OF LAND
EVOLUTION OF TERRESTRIAL LIMBS
LOSS OF GILLS & REFINEMENT OF LUNGS
= TETRAPODS (vs. PISCES)
AMPHIBIA
310 mybp
EVOLUTION OF TERRESTRIAL EGG WITH EXTRA-EMBRYONIC MEMBRANES
= AMNIOTES
SAUROPSIDS
ANAPSIDS
DIAPSIDS
SYNAPSIDS
GROUPS BASED ON SKULL FEATURES
TOPIC 7 - ANIMAL DIVERSITY
READINGS
INTRODUCTION TO CONCEPTS: PAGES 589 – 596
7 INVERTEBRATE PHYLA: PAGES 599 – 627
CHORDATES: PAGES 630 – 656
FIGURES:
32.1; 32.2; 32.3; 32.4; 32.5; 32.6; 32.7; 33.2; 33.3; 33.4; 33.5; 33.6; 33.7; 33.9;
33.10; 33.11; 33.12; 33.13; 33.15; 3.16; 33.17; 33.18; 33.21; 33.22; 33.23; 3.24;
33.25; 33.29; 33.30; 33.31; 33.23; 33.34; 33.35; 33.36; 33.37; 34.1; 34.2; 34.3;
34.5; 34.6; 34.8; 34.11; 34.13; 34.14; 34,17; 34.19; 41.9; 41.10; 42.2;
42.18; 42.21; 49.5, 49.23, 49.25
TABLES: 32.1; 33.1; 33.2; 33.3; 33.4; 33.5; 33.7; 34.1
GLOSSARY - TOPIC 7 - ANIMAL DIVERSITY, FORM & FUNCTION
Structure & Function:
Aboral, absorption, amniote, anterior, antennae, archenteron, bilateral symmetry, blastocoel, blastopore, blastula, cephalization, chelicerae, choanocyte, clevage, cnidocyte, coelom, complete gut, cranium, determinate clevage, diploblastic, dorsal, ectoderm, exoskeleton, endoderm, endoskeleton, enterocoelous, extracellular digestion, extra-embryonic membranea, filter feeder, foot, gastrovascular cavity, chitin, gas bladder, gastrula, gastrulation, germ layer, glycogen, hermaphrodite, hydrostatic skeleton, indeterminate clevage, ingestion, lophophore, mandibles, mantle, medusa, mesentery, mesoderm, nerve cord, neural crest cells, notochord, oral, paedogenesis, paired fins, peritoneum, pharyngeal slits, polyp, posterior, pseudocoelom, radial clevage, radial symmetry, radula, schizocoelous, segmentation, sessile, spicule, spiral clevage, tagmata, temporal fenestra, triploblastic, tube feet, ventral, vertebrae, visceral mass, water vascular system.
Taxonomic Terms:
Acoelomate, Agnatha, Amniote, Amphibia, Anapsid, Annelida, Anthozoa, Arachnida, Arthropoda, Asteroidea, Bilateria, Bivalvia, Cephalochordata, Cephalopoda, Cestoda, Chelicerata, Chilopoda, Chondrichthyes, Chordata, Cnidaria, Crustacea, Ctenophora, Coelomate, Deuterostome, Diapsid, Diplopoda, Echinodermata, Eumetazoa, Fleshy-finned Fish, Gastropoda, Gnathstomata, Hirudinea, Hydrozoa, Insecta, Mollusca, Nematoda, Oligochaeta, Osteichthyes, Parazoa, Pisces, Platyhelminthes, Polychaeta, Polyplacophora, Porifera, Protostome, Pseudocoelomate, Radiata, Ray-finned Fish, Rotifera, Sauropsids, Scyphozoa, Syanaspid, Trematoda, Trilobita, Turbellaria, Uniramia, Urochordata, Vertebrata.