Phylum

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Phylum

• ARTHROPODA

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Phylum Arthropoda(The Arthropods)

• Most successful animal group EVER to live!!!
• Consists of over 1 million named species, 2 of
  every 3 animals are arthropods. 1018
  individuals.
• Inhabit all ecosystems
• General characteristics
• Hard exoskeleton
• Bilateral Symmetry
• Composed of chitin - allows for great variation
  in function - biological "swiss army knives"
• Must molt as they grow
• Segmented body
• Jointed legs / Pairs of limbs
• True eyes and antennae

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SUBPHYLA (Major Groups)

• 1) Chelicerates SPIDERS, TICKS, SCORPIONS
• 2) Crustaceans  LOBSTERS, CRABS, SHRIMP,
  CRAYFISH
• 3) Myriapods MILLIPEDES, CENTIPEDES
• 4) Hexapods INSECTS

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SUBPHYLUM Chelicerates

• SPIDERS, TICKS, SCORPIONS, HORSESHOE CRABS,
  TICKS, MITES
• 2 body segments 
• 8 legs
• No antenna

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SUBPHYLUM Crustacea

• CRABS, LOBSTERS, CRAYFISH, SHRIMP, KRILL
  BARNACLES
• Over 40,000 species
• Appendages- highly specialized (biological Swiss
  army knife)
• Gas exchange thru gills

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SUBPHYLA Myriapods

• CENTIPEDES, MILLIPEDES
• Terrestrial
• Centipedes carnivores, poisonous, 1 pair of legs
  /segment
• Millipedes herbivores, 2 pairs of legs /segment

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SUBPHYLA Hexapods

• Insects 800,000 species, majority of all
  arthropods
• 3 pairs of legs
• 3 body segments
• Antennae
• WINGS (not all)
• Metamorphosis

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What happening to the BEES?

• Colony collapse disorder (CCD) is a
  phenomenon in which worker bees from a beehive
  abruptly disappear. While such disappearances
  have occurred throughout the history of
  apiculture, the term colony collapse disorder was
  first applied to a drastic rise in the number of
  disappearances of Western honey bee colonies in
  North America in late 2006. Colony collapse is
  significant economically because many
  agricultural crops worldwide are pollinated by
  bees and ecologically, because of the major role
  that bees play in the reproduction of plant
  communities in the wild.
• Problem
• Zombies?

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All About WORMS!
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Phylum Platyhelminthes FLATWORMS

• TAPEWORMS, FLATWORM
• Unsegmented worms
• No digestive cavity
• Eyespot
• Free-living
• Parasitic ? cause disease

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Phylum Nematoda ROUNDWORMS

• C. ELEGANS
• Unsegmented worms
• Digestive system (2 openings)
• Body cavity contains organs
• Free-living
• Parasitic ? cause disease
• Ex. Trichinosis (trichinella worm) - consume
  worm (uncooked meat) - worm grows in intestine-
  forms cysts in the muscles of the new host -
  symptom terrible pain in muscles

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Phylum Annelida ANNELIDS

• EARTHWORMS, MARINE WORMS, LEECHES
• Segmented worms
• Developed nervous system (brain)
• Earthworm castings ? enrich soil (worm poop)
• Leeches ? external parasites (suckers on each
  end)