580 likes | 878 Views
“ The insects will tell you everything, people lie, but insects don't lie.” Murray Marks ---forensic anthropologist, University of Tennessee. Blowfly Life Cycle. The Role of Arthropods (Phylum Arthropoda) in Animal Decomposition.
E N D
“ The insects will tell you everything, people lie, but insects don't lie.” Murray Marks ---forensic anthropologist, University of Tennessee
The Role of Arthropods (Phylum Arthropoda) in Animal Decomposition
The Role of Arthropods (Phylum Arthropoda) in Animal Decomposition Key Points:
The Role of Arthropods (Phylum Arthropoda) in Animal Decomposition • Key Points: • Following death, blow flies (Calliphoridae) and flesh flies (Sarchophagidae) are the first animals to locate and colonize the carcass – arriving within ten minutes of death.
Green Bottle Fly Phaenicia sericata, and Phaenicia cuprina (Order: DIPTERA, Family: CALLIPHORIDAE)
Hairy Maggot Blow Fly (Chrysomya rufifacies) (Order: DIPTERA, Family: CALLIPHORIDAE)
Oriental Latrine Fly Chrysomya megacephala (Order: DIPTERA, Family: CALLIPHORIDAE)
Blue Bottle Fly (Calliphora vomitoria) (Order: DIPTERA, Family: CALLIPHORIDAE)
Black Blow Fly Phormia regina (Order: DIPTERA, Family: CALLIPHORIDAE)
Flesh Flies Sarcophaga spp. (Order: Diptera, Family: Sarcophagidae)
House fly (Musca domestica) (Order: Diptera, Family: Muscidae)
Secondary Screwworm Fly (Cochliomyia macellaria) (Order: Diptera: Family: Calliphoridae)
The Role of Arthropods (Phylum Arthropoda) in Animal Decomposition Key Points:
The Role of Arthropods (Phylum Arthropoda) in Animal Decomposition • Key Points: • Following death, blow flies (Calliphoridae) and flesh flies (Sarchophagidae) are the first animals to locate and colonize the carcass – arriving within ten minutes of death. • The decay process is highly predictable with respect to: 1) the associated external insect fauna and 2) the internal bacterial fauna – passing through various stages of ecological succession from the “fresh” stage to the “skeletal” phase.
The Role of Arthropods (Phylum Arthropoda) in Animal Decomposition • Key Points: • Following death, blow flies (Calliphoridae) and flesh flies (Sarchophagidae) are the first animals to locate and colonize the carcass – arriving within ten minutes of death. • The decay process is highly predictable with respect to: 1) the associated external insect fauna and 2) the internal bacterial fauna – passing through various stages of ecological succession from the “fresh” stage to the “skeletal” phase. • see http://www.deathonline.net/decomposition/index.htm
The Role of Arthropods (Phylum Arthropoda) in Animal Decomposition • Key Points: • Following death, blow flies (Calliphoridae) and flesh flies (Sarchophagidae) are the first animals to locate and colonize the carcass – arriving within ten minutes of death. • The decay process is highly predictable with respect to: 1) the associated external insect fauna and 2) the internal bacterial fauna – passing through various stages of ecological succession from the “fresh” stage to the “skeletal” phase. • By studying these stages of decay and the abiotic conditions at the site (temperature, habitat conditions, etc…), forensic scientists can accurately predict the time of death or post-mortem interval (PMI).
The Role of Dipterans (true flies) in Determining Time of Death • Flies are ectotherms, thus growth rates for a particular species are primarily a function of time and temperature.
The Role of Dipterans (true flies) in Determining Time of Death • Flies are ectotherms, thus growth rates for a particular species are primarily a function of time and temperature. • If you know the temperature and the size of the larvae (maggot), you can determine the time of initial colonization.