Images Dated 8th January 2003

Blowfly pupa hatching, SEM

Blowfly pupa hatching. Coloured scanning electron micrograph (SEM) of a Calliphora vicina blowfly adult emerging from its pupa. A blowfly lays its eggs on dead bodies and this behaviour is studied by forensic entomologists. Eggs generally hatch within 24 hours. A Calliphora larva (maggot) feeds on the decaying flesh for 2-3 weeks, and then lies dormant in its pupa, slowly developing into the adult winged form. The head with its compound eyes (blue) is emerging from this pupa. The adult form generally lives for a few weeks. After mating, the females lay eggs and continue the cycle. Hatching (by incubation) of pupae found by a dead body can pinpoint the time of death. Magnification unknown

© VOLKER STEGER/SCIENCE PHOTO LIBRARY

Blowfly laying eggs, SEM

Blowfly laying eggs. Coloured scanning electron micrograph (SEM) of a female Lucilia sp. blowfly laying her eggs (lower left). A blowfly lays its eggs on dead bodies. This behaviour is studied by forensic entomologists. A blowfly detects a dead body by the odour of decomposition, and can arrive at a corpse minutes after death and lay up to 300 eggs. The decaying flesh is food for the maggots (fly larvae) that hatch from the eggs within 24 hours. These two-millimetre-long eggs are laid in patches around moist orifices such as the nose, ears and eyes, as well as open wounds. Fresh and unhatched blowfly eggs will indicate a very recent time of death. Magnification unknown

© VOLKER STEGER/SCIENCE PHOTO LIBRARY