Immersing Corpses in Water

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Immersing Corpses in Water

• 4/10/08

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Overall Effects on Corpse

• Decomposition generally retarded
• Decomp begins in head region
• Skin of hands and feet
• Livor mortis may not appear
• Bloating

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Overall Effects on Corpse

• Finger and toenails easily detachable
• Skeletonization

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Faunal Associates

• Ectoparasites
• Fleas
• Body lice

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Carrion Community Associates

• Pig carcass study by Payne
• Stage one submerged fresh
• Bloat
• Aquatic Insects

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Hydrophilid Beetles

• Coleoptera Hydrophilidae
• Water scavenger beetles
• 284 species in North America
• 1-40 mm
• Long palpi
• Larvae predatory, adults scavengers

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Hydropsychid Caddisflies

• Trycoptera Hydropsychidae
• Water nymph
• 146 species in North America
• Adults 6-19 mm
• Larvae streams and rivers
• Feed on algae, diatoms, crustaceans, insects

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Chironomid Midges

• Diptera Chironomidae
• Non-biting midtes
• 700 species
• 1-10 mm
• Resemble mosquitos
• Larvae aquatic

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Simulidae Larvae

• Diptera Simulidae
• Black flies
• Blood feeders
• Small, black/grey
• Larvae aquatic

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Heptageniid Mayflies

• Ephemeroptera Heptageniidae
• Mayflies
• 500 species
• Clear wings, prominent venation
• Nymps aquatic, flattened, streamlined

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Carrion Community Associates

• Stage two submerged fresh
• Early Floating
• Exposed abdomen eggs
• Submerged portions still inhabited by organisms
  in stage one

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Carrion Community Associates

• Stage three Floating Decay
• Blowfly eggs hatch
• Oviposition ceased by Day 3
• Coleoptera
• Silphids, Staphylinids, Histerids

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Carrion Community Associates

• Stage four Bloated Deterioration
• Many maggots, beetles
• Most tissues gone

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Carrion Community Associates

• Stage five Floating Remains
• Few maggots
• Histerid beetles
• Small flies Sphaerocerids, Phorids,
  Drosophilids, Psychodids
• Stage ends when remains sink

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Carrion Community Associates

• Stage six Sunken Remains
• Decomp completed by bacteria and fungi

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Postmortem Submersion Interval

• Make use of organisms which attach themselves to
  substrate
• Understand differences between moving and still
  water organisms
• no purely sarophagous aquatic insects

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Ecological Function

• Food for invertebrates and fish
• Shelter
• Attract secondary scavengers
• Substrate for producers
• Substrate for grazers

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Saltwater Submersion

• Fauna almost completely different from fresh
  water
• little studied
• Barnacles
• Shrimp, prawns, crabs

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Any Questions?