Download presentation
Presentation is loading. Please wait.
Published byOswald Cox Modified over 6 years ago
1
Forensic Entomology – Using insects to assist in time-of-death analysis
2
Egg to Adult… about 2 weeks depending on Temperature and Humidity…
3
2 – Eggs hatch into larva (maggots) in 12-24 hours
1 – Adults lay eggs on carcass at wound areas and/or body openings (nose, eyes, ears, anus, etc.) 2 – Eggs hatch into larva (maggots) in hours 3 – Larvae continue to grow and molt (shed exoskeletons) through the various stages. 1st Instar - 5 mm long after 1.8 days nd Instar - 10 mm long after 2.5 days 3rd Instar – mm long after 4-5 days 4 – The larvae develop into pupa after burrowing in surrounding soil, after 4-5 days. 5 – Adult flies emerge from pupa cases after 6-8 days.
4
Decomposition of a baby pig https://www. youtube. com/watch
Professor from University of Michigan
5
STARTS after 1-2 hrs “FULL” after 8-12 hrs ENDS: after 24-48 hrs
Rigor Mortis STARTS after 1-2 hrs “FULL” after 8-12 hrs ENDS: after hrs
6
Rigor Mortis: “Stiffness of Death”
PATHWAY eyelids jaw face torso limbs Relaxes in the same order
8
Algor Mortis: ‘Coolness of Death’
Beginning at 37⁰ C, body temperature drops steadily Systems which maintain HOMEOSTASIS not working Taking temp of corpse…rectal (best) or armpit. Mouth muscles relaxed (or Rigored) …tongue won’t stay on top of thermometer. Thinner people cool faster than fat.
9
Livor Mortis: “Color of Death”
Heart stops = blood stops cycling RBCs and plasma gravitate to lowest point
10
STARTS: after 1-2 hrs “FIXED”: after 6-8 hrs
-- body position may not agree with lines
12
Vitreous Humor Not much? Cloudy? Broken blood vessels?
= Dead longer… Cloudy? Broken blood vessels? = likely strangulation
13
When Did She Die ? Anatomy & Physiology
Homeostasis = “steady state” hypothalamus pituitary cells making ATP ATP allows muscle cells to contract and relax. Your cells can store some, but not much… The last little bit is probably used up in Rigor Mortis – the final contraction
14
When Did She Die ? Anatomy & Physiology
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.