Animal Diversity

1
Animal Diversity
2
What is an Animal?

• Multicellular, heterotrophic, eukaryote that
  obtains nutrients by ingestion
• Lacks a cell wall
• Muscle cells and nerve cells
• Reproduce sexually by egg and sperm (haploid
  cells)

3
Nine Phyla of the Animal Kingdom

• MEN wear CAPs
• Mollusca, Echinodermata, Nematoda
• Cnidarians, Chordata, Arthropoda, Annelida,
  Platyhelminthes, and Porifera

4
Invertebrates
5
Body Plans

• Radial Symmetry parts arranged around a central
  axis
• Bilaterally symmetry mirror-image
• Anterior
• Posterior
• Dorsal
• lateral

Dorsal
Posterior
Anterior
Ventral
6
Body Plans

• Sponges, cnidarians, and flatworms lack a body
  cavity

Tissue-filled region(from mesoderm)
Body covering(from ectoderm)
Digestive tract(from endoderm)
7
Body covering(from ectoderm)
Muscle layer(from mesoderm)
Pseudocoelom
Digestive tract(from endoderm)
Body covering(from ectoderm)
Coelom
Tissue layerlining coelomand suspendinginternal
organs(from mesoderm)
Digestive tract(from endoderm)
Figure 18.7B, C
8
Porifera

• Stationary animals, radial symmetry, water enters
  through pores
• Example Scypha
• Choanocytes inner layer of flagellated cells
  that sweep water through the sponges body

9
Choanocytes Filters Food in Sponges
Choanocyte incontact withan amoebocyte
Pores
WATERFLOW
Skeletalfiber
Centralcavity
Choanocyte
Flagella
Amoebocyte
10
Porifera

• Amoebocytes produce skeletal fibers
• Suspension Feeders catch bacteria in mucous on
  choanocytes
• Sponges resemble choanoflagellates (colonial
  protist). Molecular studies suggest animals
  arose from choanoflagellates.

11
Cnidarians

• Radial Symmetry
• Simplest animals with symmetry
• Examples Hydra, Jellyfish, Sea Anemones and
  Corals
• Digestion System is incomplete (gastrovascular
  cavity) no anus
• Water enters and leaves through mouth
• Cnidocytes are specialized stinger cells to
  immobilize prey

12
Cnidarians

• Exist in two forms
• Medusa umbrella-like, movable, tentacles, mouth
  on underside tentacles push food into mouth into
  gastrovascular cavity

13
Cnidarians

• Polyp stationary, cylindrical body with
  tentacles mouth on top at the hub of the
  tentacles

14
Platyhelminthes

• Flatworm thriving in freshwater, ribbon-like
• Free-living and parasitic
• Incomplete digestive systems (gastrovascular
  cavity)
• Bilaterally symmetrical
• Three Groups Planarian, Flukes, Tapeworms

15
Planarian

• Eyespots, nervous tissue with simple brain,
  gastrovascular cavity
• Mouth on ventral surface
• cilia moves food into mouth

Digestive tract(gastrovascularcavity)
Nerve cords
Mouth
Eyespots
Nervoustissue clusters
16
Tapeworm

• Parasitic adults live in digestive tracks of
  animals long ribbon-like body no digestive
  tract absorption of nutrients
• Ripe eggs may break off of posterior end of
  ribbon and leave host via feces.

Units withreproductivestructures
Head
Hooks
Sucker
Figure 18.6C
17
Flukes

• Parasitic
• Infects humans in Africa, Southeast Asia, and
  South America
• Schistosoma may cause severe abdominal pain,
  anemia and dysentery

18
Nematoda

• Roundworms (pseudocoelom)
• Covered by tough, non-living
• exoskeleton called cuticle
• Free-living and parasitic
• Example 1) hookworms attach to intestinal wall
  and suck blood 2) heartworms deadly to dogs
  spread by mosquitoes 3) roundworms Trichinella
  spiralis, undercooked pork

19
Mollusks

• Soft Body protected by a hard shell
• Example snails, slugs, oysters, clams, octopus,
  and squids
• Complete digestive system (mouth and anus)
• Three main parts 1) foot, 2) visceral mass, and
  3) mantle

20
Mollusks

• The mantle can form the mantle cavity for the
  anus and gills
• Unique structure called radula scrapes up food
• True coelom, circulatory system

21
VISCERAL MASS
Coelom
Reproductiveorgans
Kidney
Heart
Digestivetract
MANTLE
Shell
Mantlecavity
Radula
RADULA
Anus
Gill
Mouth
Nervecords
FOOT
Mouth
Figure 18.9A
22
Gastropods

• Gastropods live on land and water, largest group
  of mollusks distinct eyes on tip of tentacles
• Examples snails and slugs

23
Bivalves

• Bivalves clams oysters, mussels and scallops
• Shelves divided into two halves
• Somewhat sedentary
• Numerous eyes in fringed edges

24
Cephalopods

• Cephalopods built for speed and agility
• Large complex eyes
• Mouth located at the base of the foot
• no outer harden shell

25
Annelida

• Segmentation is the subdivision of some or most
  of the body into a series of repeated parts, or
  segments
• Thrives in freshwater and damp soil
• Three large Groups
• Earthworms
• Polychaetes
• Leeches

26
Earthworm

• The segmented bodies of annelids give them added
  mobility for swimming and burrowing

Anus
Brain
Mainheart
Coelom
Digestivetract
Segmentwalls
Mouth
Accessoryheart
Nerve cord
Excretory organ
Blood vessels
27
Polychaetes

• Eats its way through the soil
• Valued to farmers to till the soil with waste
• Polychaetes
• Sandworm and
• Christmas Tree
• worm
• lives on sea floor
• largest group

28
Leeches

• Blood Sucking
• Produces beneficial saliva that keeps blood from
  clotting
• prevents clots from lodging into the heart
• Used to remove blood from bruised tissue or
  recently attached fingers or toes

29
Arthropoda

• Most numerous phylum
• Jointed appendages
• Exoskeleton made of chitin (polysacharride)
• Molting shedding of exoskeleton
• Five major groups

30
Cephalothorax
Abdomen
Thorax
Head
Antennae(sensoryreception)
Swimmingappendages
Walking legs
Mouthparts (feeding)
Pincer (defense)
Figure 18.12A
31
Five Major Group of Arthropoda

• Horseshoe Crab has remained the same over
  several million years
• Arachnids scorpions, spiders, ticks, and mites

32

• Crustaceans water dwelling lobsters, crayfish,
  shrimps and crabs
• Millipede/Centipede 2 pairs of legs per
  segement/1 pair of legs per segment

33
Insects

• Insects largest group of Arthropoda
• Each insect has three main parts
• Head, thorax, and abdomen
• 1 or 2 pairs of wings
• 7 major orders
• Orthoptera - grasshopper
• Odonata damselfly dragonflies

34
Head
Thorax
Abdomen
Antenna
Forewing
Eye
Hindwing
Mouthparts
Figure 18.13A
35

• Hemiptera water strider, stink bug, bedbugs
• Coleoptera beetle largest group
• Lepidoptera moth and butterflies
• Diptera mosquito, houseflies, gnats,
  fruitflies
• Hymenoptera wasp, bees, ants

36
Echinodermata

• All marine (sea urchins, starfish)
• No anus
• Lack body segments
• Bilateral symmetry
• Endoskeleton coelom
• Moves by tube feet
• Tube feet function in gas exchange and feeding

37

• The water vascular system has suction-cup-like
  tube feet used for respiration and locomotion

Anus
Spines
Stomach
TUBE FEET
CANALS
Figure 18.14A
38
Chordata

• In order to be in the phylum Chordata, the
  organism must have
• Dorsal, hollow nerve cord
• Notochord
• Pharyngeal slits
• Post-anal tail

39
Chordata

• Chordata is divided into to groups, Invertebrate
  and Vertebrate.
• Invertebrates include Tunicates and Lancelets
• Vertebrates include 1) Chondrithchtyhes, 2)
  Osteichthyes, 3) Amphibians, 4) Repitles, 5)
  Avians, and 6) Mammals.

40
Invertebrate Chordates

• Tunicates Larva has all 4 characteristics
• Tunicate Adult only has pharyngeal slits left
• Lives as a suspension feeder, stationary

POST-ANAL TAIL
DORSAL, HOLLOWNERVE CORD
PHARYNGEALSLITS
Musclesegments
Mouth
NOTOCHORD
LARVA
41
Invertebrate Chordates

• Lancelets has all 4 characteristics
• Resembles tunicates at larval stage

42
Vertebrates
43
Vertebrates

• Lamprey belong to a primitive group called
  Agnathans which are fish-like with no hinged jaw
  mud-suckers or suspension feeders believed that
  fish have evolved from lampreys

44
Vertebrates

• Chondrichthyes (cartilaginous fish) sharks,
  rays, skates
• Keen vision, electrosensors
• Lateral line system row of sensory organs used
  to detect water pressure

45
Vertebrates

• Osteichthyes (bony fish)
• Largest group of vertebrates
• Lateral line system
• Swim bladder
• Operculum
• 3 Classes 1) ray-finned, 2) lobe-finned, and 3)
  lungfish

46
Boney Fish
BONY SKELETON
OPERCULUM
Gills
SWIM BLADDER
47
Vertabrates

• Amphibia (double-life)
• Aquatic and terrestrial
• Frogs, toads, and salamanders
• Lays eggs in water
• First terrestrial vertebrate
• As a tadpole, uses lateral line system, gills,
  and finned tail
• As a frog, develop legs, lungs, eardrums, insect
  eating.

48
Vertebrates

• Reptiles
• Snakes, lizards dinosaurs, turtles, crocodiles
  and alligators
• Has tough protein keratin which keeps the body
  from drying out
• Amniotic egg (fluid-filled sac)
• Complete life cycle on land
• Ectothermic (absorbs
• external heat from sun)

49
Vertebrates

• Aves
• Birds probably evolved from small dinosaur
• Body has been modified for speed no teeth,
  feathers have hollow shaft, shape of
  wing/feathers, high rate of metabolism, keen
  senses and powerful muscles.

50
Vertebrates

• Mammalia
• Believed to have evolved from reptiles
• Endothermic
• Hallmark traits hair and mammary glands
• Three major groups of Mammals
• Monotremes egg laying mammals that supplies
  milk (platypus)/ no placenta

51
Vertebrates

• Marsupials give birth to young and they live in
  pouch (kangaroo)/ placenta
• Eutherians (placentals) placenta/give birth