And has not such a Story from of Old
Down Man's successive generations roll'd
Of such a clod of saturated Earth
Cast by the Maker into Human mold?
--Omar Khayyam, Rubaiyat, FitzGerald, Fifth Edition

Campbell and Reece Chaps 32, 33 & 34 (a good bit of the semester)

here is a comprehensive site on animal diversity

Animals: Protozoans vs Metazoans.
naive: vertebrates and invertebrates

Major developments with multicellularity:
vascular and gut (then one way gut)
primitive: sponges - Parazoa vs. eumetazoa
two way: cniderans, flat worms
one way: (two openings) roundworms & up
symmetry: none, "radial" (even star fish is bilateral), bilateral - Radiata vs. bilateria
cephalization (not shown in figure, but there is a tendency for nervous system to concentrate in head)
body cavity (coelom with peritoneum) acoelomates vs pseudocoelomates
TRANSPARENCY Fig. 32.6 body cavity seen above roundworms
TRANSPARENCY Fig. 32.1 Embryology
Zygote, Cleavage, Ball, Infold,- gastrulation
TRANSPARENCY Fig. 32.7 (additional coelom mechanisms)
protostome: molluscs, annelids, arthropods
blastopore becomes mouth
spiral cleavage
deuterostome: echinoderms, chordates
blastopore becomes anus
radial cleavage
(even though arthropods and molluscs can be high, comparative embryology tells us that echinoderms are closer)
body support
because of organs, organ systems, need
nervous system (integration, also hormones)
symmetry (none, radial vs bilateral)
none - porifera
radial - cniderans and echinoderms
bilateral - others

I will not emphasize all phyla

CHAPTER 33 Invertebrates

Porifera - sponges - TRANSPARENCY Fig. 33.3
have some specialized cells:
choanocytes with flagella which beat
amoeboid cells digest and distribute
spicules of calcium carbonate (chalk)
or silica (glass)
no nerves

Cnideria (Coelenterates) - TRANSPARENCY Fig. 33.4
several layers, nervous system (net), radial symmetry, mouth only
medusa or polyp - tentacles, attached sea anemones, corals
TRANSPARENCY Fig. 33.7 - life cycle of hydrozoan
alternation of generations (medusa or polyp) in some cases
TRANSPARENCY Fig. 41.11 Cnidera look ahead to digestion chapter
One opening, food and waste must use that one opening

Platyhelminthes - flatworms - bilateral
Class - free living flatworms TRANSPARENCY Fig. 33.10 Class Turbellaria
- flukes (parasites) Shistosoma TRANSPARENCY Fig. 33.11 Trematoda
Snails water Africa
- tapeworms TRANSPARENCY (Fig. 33.12) class Cestoda

Phylum Nematoda
why is there so little coverage? (considering how important C. elegans is for genetics and development?)
2 ended gut, pseudocoelom, simple 300 nerves
free living (soil) Caenorhabditis elegans genetics
Trichinella (pork) US, not as bad as before (4 infested meals/yr) not in Europe (they have raw pork dishes, but they have mad cow disease). Pick trichinosis up from eating meat (muscle) with cysts.
hookworms, pinworms, dog heart worms

Mollusca 100,000 species, second largest phylum
Class Gastropod (stomach - foot) snails Escargo
Pelecypoda (clams and bivalves) New England & Manhattan clam chowder
Cephalopoda squid octopus nautilus - largest Calamari
Good digestion. very good nervous system
squids can be biggest invertebrates

Annelids TRANSPARENCY Fig. 33.23 segmentation like arthropods
digestion with crop, gizzard, 5 paired hearts, coelom
earthworms - class Oligochaeta (oligo - a few)
"medicinal" leeches - class Hirudinea (Bogart Hepburn movie African Queen)
Polychaeta - marine worms

Arthropods- jointed legs largest phylum
Exoskeleton, chitin (fungus) molt soft shelled crabs
Chilopoda - centipedes
Diplopoda - millipedes
Crustacea - crabs, etc. TRANSPARENCY Fig. 33.26
Study of insects is entomology, Dr. Camilo represents that field
Insects -TRANSPARENCY Fig. 33.33
complex, metamorphosis - stages in fly life (egg, embryo, 3 larval instars, pupa, adult (imago)
2/3 species Entomology - TRANSPARENCY Table 33.6 lists orders
Brain hormone to prothoracic gland (molting hormone)
corpora allata (JH)
eclosion hormone
Fruitfly Drosophila is very useful in genetics, and Drs. Coulter and Tsubota do Drosophila genetics in their labs.

medussa - jellyfish SLIDE
Portuguese man of war SLIDE
free living flatworms SLIDE
tapeworms SLIDE
SLIDE: dog heart worms from mosquito, poison
Insects - complex, metamorphosis 4 SLIDES
insects that have complete metamorphosis are called "holometabolous"
SLIDE Limestone wall in "white campus" at Mizzou


Echinoderms - spiny skinned sea stars, sea urchins, sea cucumbers - starfish eat bivalves

Chordates - notochord (becomes support usually), dorsal nerve, pharyngeal gill slits, tail
"Ontogeny recapitulates phylogeny" gills, tail, etc
subphylum cephalochordata Lancets TRANSPARENCY 34.4A
subphyla:Tunicates - Urochordata TRANSPARENCY Fig. 34.3


vertebrate diversification over geological time
TRANSPARENCY from another book emphasizes success, extinction

classes: Agnatha-jawless fish - lampreys
Placoderms - first jaw fish, extinct
Chrondrichthys - cartilagenous
Ostreichthys - bony fish. SLU's Biology Department has several people who are interested in fish, including Dr. Nordell, Dr. Mayden and Dr. Wood. Dr. Aspinwall teaches a course, BL A-428 Biology of fish.
Amphibia metamorphosis interest in development
Reptiles internal fertilization. Here is a nice site about reptiles. Dr. Aldridge is SLU Biology's herpetologist, and he teaches BL-A426 Herpetology. He is also the person to contact to find out about Tri-Beta, the biology "club."
Birds -separate evolution from reptiles. Dr. Valone teaches a course in Ornithology
Mammals (named after mammary glands) adaptive radiation from reptiles
Monotremes (egg, platypus)
Marsupials (pouch) (opposums, kangaroo)
Orders TRANSPARENCY Table 34.1
Insectivores moles, shrews
Carnivora - cats, dogs etc
Artiodactyla - pigs, sheep, cattle, deer, giraffes
Perissodactya - horse, zebra, rhinoceroses
Sirenians - sea cows
Edenta - sloth, anteaters, armadillos
Chiroptera - bat
Langomorpha - rabbit
Proboscidea - elephant
Cetacea - whales

Primates TRANSPARENCY Fig. 34.35
Primitive primates (prosimians)lemurs, tree shrews
New world monkeys spider monkeys, prehensile tail
Old world monkeys baboons, macaques (rhesus) color vision
(rhesus used in research - centers)
(baboons - film of social life)
Great apes - Chimpanzee present controversy used in AIDS research
Gorilla - very different in zoos, Orangutan, Gibbon

Man TRANSPARENCY Fig. 34.38 fossils not in good places
scavange, animals, native groups want buried
Australopithecus afarensis Lucy 2.8 - 3.6 MYA
walked upright before brain grew
Australopithecus africanus (tool use) East Africa

chimps Jane Goodall, Darwin's finch - tool
4 million yrs ago
Homo habilis (crude chipped stones) (stone age)
2 million yrs ago
Homo erectus (Java, Peking)
1.5 million yrs ago
Homo sapiens Neanderthal
200,000 yrs ago
Cro-Magnon paint in caves
30,000 yrs ago
Homo sapiens
brain change .05 cc/generation
future change may be influenced by social acceptance

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