Chapter 17: The Evolution of Animals  1 Lecture, & labs for three weeks

Summary: Animals experienced many great leaps forward:
A) Origins, larvae & embryos
B) In invertebrates: fig 6, Lab Ex week 5
C) In vertebrates & early primates: fig 32 & 41, Lab Ex week 6
D) In human evolution: fig 43, Lab Ex week 7

Biol & Soc: FDA: blowfly maggots to clean wounds, & medicinal leech as clot buster & after microsurgery
Limulus, blood is used to detect a toxin
A. Origins of Animal Diversity: eukaryotic, multicellular, heterotroph, ingestion etc, embryo

1) Animals evolved from unicellular protists, protozoa, probably flagellate(s)
    Fig 4 possible steps: individual > colony > hollow sphere > germ cells & body cells > internal cavity > sponge?
    If true, each stage must have fitness, possibly still be around (protozoa are) &/or be in fossil record

2) This evolution sequence is similar to generic animal embryo development sequence, fig 3:
     fertilization > zygote > morula > blastula > gastrula > embryo > (larva/metamorphosis) > adult
    starfish: all stages & source, & world's largest cell.
3) Gastrulation begins at the anus in most phyla, but not all:
    protostome (mouth first) or deuterostome (anus first)  and many excellent illustrations
    Gastrulation produces 3 stem/germ cell layers: fig 8: ectoderm/blue, mesoderm/red, & endoderm/yellow

4)  In their embryo development animals recapitulate their evolution was first proposed for vertebrates
     Haeckel suggested in 1892 that embryo development may recapitulate evolution,

5) Cambrian explosion: picture, fig 5, movies: significance: all major body plans appeared, animations, evidence
    Explanation: 1) extends diversification already begun, 2) competition, 3) new homeotic genes for development
    Homeotic genes determine what develops at each segment, from head to tail: mutations
B) LAB: WEEK 5, 2/14, Ex 11.4: A Survey of the Kingdom Animalia: FOR KIDS
Animals, like plants, experienced a series of great leaps forward, which produced new types, or phyla
NOTE: Use your textbook to guide drawing & describing the specimens
Dichotomous Key < does not use the great leaps forward in order, but gets to the same result

DO 11.4 A & B: Using specimens, identify, draw & describe one animal from
each major animal phylum in textbook = 9, Wiki has 10, adds Rotifera, 
Include a description of the great leap(s) forward that produced each new type:
Porifera, Cnidaria, Platyhelminthes, Nematoda, Mollusca, Annelida, Arthropoda, Echinodermata &
& among Chordata do one of the invertebrates = tunicates & lancelets

B. Nine Major Animal Phyla (9 + Rotifers): fig 6, lab Ex 11.4, & really 30+ phyla
.ppt: covers entire chapter, to use it or not to use it? no because it uses textbook
Explain how each group feeds: ingestion, digestion, absorption & elimination

1) multicellular & body cavity open to environment, but no true tissues: sponges/Porifera,
fig 9 & 10 < body wall, sponges, all stages & sort of gastrula, use, choanocyte/larva.

2) radial symmetry: cnidarians, fig 7, hydra: two cell layers, life cycle, in pictures

3) bilateral symmetry, no body cavity: flatworms/Platyhelminthes, wiki
structure: three layers: ectoderm, mesoderm & endoderm,
which lines G.I. tract, which has only one opening: fig 14 & 15,

4) fig 8, body cavities, evolution pseudocoelom: roundworms/Nematoda, fig 16a,b,
Two traits not in previous phyla: have complete digestive tract (two ends), &
pseudocoelom - false body cavity: is not fully lined with cells

5) true coelom from cell masses: mollusks, three parts, fig 17,
1) foot, 2) mantle, 3) visceral mass (& usually protective shell)
Distinguish among (fig 18)
gastropods = stomach + foot:
bivalves = shell has two sides, like zebra mussel or Shell oil sign
cephalopods = headfoot, octopi are brainy.

6) annelids, fig 19, segmented, coelom, nervous system: brain,
nerve cord & ganglia, closed blood circulation, segmental excretory organs, digestive tract, repoductive organs
Distinguish among earthworms, body plan, polychaetes (many bristled) & leeches (carnivorous), fig 20

7) arthropods: have an exoskeleton: very protective, is shed for growth (moulting), limits sensory input, limits size?.
Know: arachnids,  crustaceans,  millipedes,  centipedes, & insects, with examples: fig 21-26.

8) True coelom from digestive tube: Echinoderms: spiny skin, larva has bilateral symmetry = link to chordates
Echinoderms have water vascular system: scroll: hydrostatic skeleton for movement

9) Chordates: special feature is notochord.  All vertebrates are chordates, but
fig 30, chordates includes two invertebrate groups lancelets, in lab amphioxus, & tunicates (in lab) fig 29.
Chordates' four characteristics: notochord, dorsal hollow nerve cord, pharyngeal slits & post-anal tail,
tunicates have all four when larvae

Summary: nine/ten major animal phyla, differences determined by:
true tissues?, type of symmetry?, type of digestive organ?, type of body cavity(ies)?,

CHECKPOINTS p 348 & 358
 Porifera, Cnidaria, Platyhelminthes, Nematoda, Mollusca, Annelida, Arthropoda, Echinodermata &
& among Chordata do one of the invertebrates = tunicates & lancelets
1. Chordates are most like which other animal phylum? ans
2. How is animal nutrition different from fungi?
3. Why is the Cambrian "explosion" so named?
4. Pizza symmetry is ? , a fork's symmetry is ?
5. A fully lined body cavity between skin and guts is a true ?
    Roundworms have a partially lined body cavity called a ?
1. How does the digestive tract of a jelly differ from a roundworm?
2. How are sponges fundamentally different from all other animals?
3. Sea anemone phylum? ans  blood fluke phylum? ans
4. Which arthropod group is mainly aquatic
5. Which mollusc group: snail ?, clam ?, squid ? ans
6. Compare echinoderm & arthropod skeletons

SKIP More Review  four current issues
Segmentation? annelids, arthropods & chordates have it, but echinoderms?
Are arthropods or chordates the most complex animals?
Vertebrates' (next) advantage over arthropods is size, or is size a disadvantage?

C. LAB EX WEEK 6, 2/21: Vertebrate Genealogy & Adaptation.  More Lab Ex.,  FOR KIDS
Kimball clear, Farabee's good pictures, compares groups but too much     K-12: Vertebrates
Use textbook's groups: & use either textbook, specimens or www
1) Lampreys, 2) Cartilaginous fishes, 3) Bony fishes, 4) Amphibians, 5) Reptiles, 6) Birds
    Mammals: 7a) monotremes, 7b) marsupials & 7c) eutherian
    Primates: 8a) Lemurs etc, 8b) Tarsiers, 8c) Monkeys

LAB EX: Choose one from each group (12) above, name it, & convince yourself & write down
the adaptations that it has in the folowing list, & include skeletal adaptations described below. 
8) Primates: include 8a) Lemurs etc, 8b) Tarsiers, 8c) Monkeys, 8d) Hominoids (below)
Primate adaptations for living in trees: shoulder joints, dextrous, nails replace claws, sensitive fingers
Early Evolution, Prosimians: fig 40, arboreal, good smell, some claws, partial binocular vision
Biological topics, Mural, Resource.

A way to study the adaptive radiation among the vertebrates is to study their skeletons. 
E.g. Limbs in land vertebrates & cetaceans evolved from primitive tetrapod (4 limbs).
In primitives each limb is supported by a girdle (pelvic in the hip region, pectoral in the shoulder). 
The pelvic girdle is attached to the vertebral column; while the pectoral girdle is unattached. 
The limbs consist of a single bone in the upper limb (the humerus or femur respectively),
& two parallel bones in the lower region (radius & ulna in forelimb, tibia & fibula in hind limb). 
A set of small bones are carpals in wrist, & tarsals in ankle. 
Five longer bones, the metacarpals or metatarsals comprise the hand or foot, together with
the fingers & toes (or digits): each composed of several smaller bones, the phalanges.
Skeletology: vertebrate skeletons, some images, use google images for specific type
Determine How Skeletal Structure Varies with Mass, Gait, Stance & Dietary Habits
Throughout the evolution of the vertebrates this basic form has been much modified. 
Such modification has resulted in (includes O'Keeffe paintings):
a) changes in the position of limbs in relation to the long axis of the body.
b) reduction in the kinds and number of bones in the lower limb regions.
c) elaboration of some structures, and total elimination of others.
WEEK 6 LAB EX ENDS

8d) Hominoids, includes apes & humans
HUMAN EVOLUTION: summary in one drawing,  back to the future?
Unlike chimps & gorillas, the orang does not knuckle walk but walks upright - a pre-adaptation to bi-pedal locomotion.
Textbook Topics:
1) Some Common Missconceptions:
     modern apes are not our ancestors but distant cousins,  AE Lab Ex: use DNA to make cladogram,
     the tree of human evolution has many branches,  homo only,
     True: human characteristics evolved at different times & rates, bipedalism came first
2) Australopithecus: the Antiquity of Bipedalism: Orrorin, wiki, 6 mya. Lucy, wiki, (4 mya), fig 43, buy her!
3) Homo habilis: the Evolution of Inventive Minds, 3 mya: Homo habilis,
4) Homo erectus: the Global Dispersal of Humanity, 2 mya: Homo erectus,  Neanderthals,
5) The Origin & Dispersal of Homo sapiens, last 200,000 years, Ethiopia
    mitochondrial Eve: 140,000 years ago, east Africa
    Y chromosomal Adam: 60-100,000 years ago, Africa 
6) Cultural Evolution: began ~2 mya, made tools, organized labor, lived in communities

More Resources
Human Ancestry < videos with commentary & fossil record.
Anthropology tutorials, Kimball, everything, DNA & mtDNA, Each stage & figures, all groups:
Human evolution: multiregional (one dispersion) or monogenesis, two?,  fig 44.
.multiregional and monogenesis models of human evolution (scroll half-way). 
Summary, several human evolution pages, More Links.Genetic code. & .clock. & .example

Evolution Connection: Earth's New Crisis: current mass extinction, but all life are our cousins

Earthworm dissection..2..section..2..virtual dissec.,
Kimball,  Farabee,  slide show,  source,  K-12,  dead & alive,  one more,  Wiki,  fig 6: phyla & links,  Wiki phyla list