- Slides: 80
FORENSIC ANTHROPOLOGY FORENSIC ENTOMOLOGY
Forensic Entomology �The study of insects and their relationship to time of death. � commonly called upon to determine the postmortem interval or "time since death" in homicide investigations.
Entomology � based on the age of the insect present • "Time Since Colonization" � number of different techniques • • species succession larval weight larval length accumulated degree hour technique
Life Cycle Stages of a Blow Fly �Stages • 1. Egg • 2 – 4. Larva • 5. Pupa • 6. Adult
Life Cycle of the Blow Fly �Blow Flies are most commonly the first insects to infest a dead body. �Lay eggs around natural body orifices • Nose • Eyes • Ears • Anus • Penis • Vagina • Open Wounds (Gun shot, Stab, Puncture wounds)
Life Cycle � 1 St Stage Eggs � 2 Nd Stage First Stage Larva hatch from eggs • Maggots feed on dead tissue. � 3 rd Stage Second Stage Larva Molts from first stage larva � 4 th Stage Third Stage Larva Molts from second stage larva Masses of third stage maggots produce enough thermal energy to increase ambient temperature up to 10 deg C
Life Cycle � 5 th Stage Third stage Larva molts into Pupa � 6 th Stage Pupa develops into adult fly � Approximately 2 weeks from egg to adult � Depends on species and environmental conditions Temperature/Exposure/Humidity
Forensic Entomology – NAT GEO �https: //www. youtube. com/watch? v=vwj- fvo. LJ 3 M
CONCEPT CHECK Mar 2 �You will need a half sheet of paper. �Give the other half to your neighbor. �Be kind to the trees. JOIN THE PTHS ENVIRONMENTAL CLUB!
CONCEPT CHECK Mar 2 � 1. Which stage of the blow fly’s life cycle is capable of raising the surrounding air temperature by up to 50 degrees F? � 2. What are three factors that will affect the time it takes an insect to complete its life cycle? � 3. Which two factors are used to identify the different larval stages of a blow fly? � 4. How many stages are present in the life cycle of the blow fly?
AGENDA Mar 2 �Objective: Describe the role of a forensic entomologist. � 1. ADH and Eclosion Time � 2. Effects of Environmental Temperature � 3. MP 1 Project Teams � 4. Homework and Review • Complete the ADH Worksheet • QUIZ This Week – DATE TBA
Accumulated Degree Hours � Technique used to determine Eclosion • period of time it takes an insect to hatch from an egg. � Eclosion times have been tabulated to complete this development in various insect species. � In a blow fly, this time has been determined to be 21. 2 hours � ADH = Temperature in C x Eclosion of species
Accumulated Degree Hours � Thermal energy required to complete a life cycle stage. � Based on a mean temperature of 20 degrees C � For a blow fly • ADH = 20 deg C x 21. 2 hours • Average ADH = 424 degree hours for a blow fly to emerge from its egg • For a specific environmental temperature ADH is divided by the temperature
Calculating Eclosion using ADH � For a specific environmental temperature � Average ADH is divided by the temperature � At 25 degrees C 424 hours / 25 = 17 hours �Eclosion of a blow fly at 25 C = 17 hours
ADH Review Mar 3 �Eclosion for a black blow fly has been determined to be 23 hours. An average ADH for this insect is 424 degree – hours. �What was the environmental temperature of the crime scene where these insects were collected?
ADH Review Mar 3 424 deg – hours _______ = Eclosion time Enviro Temp �Solve for Enviro Temp. 424 deg-hours Enviro Temp = ______ = 18. 4 deg C 23 hours
AGENDA Mar 3 �Learning Objective: Identify the procedures used to collect and preserve insects from a body. � 1. ADH Extension – Value to Law Enforcement � 2. Stages of Decomposition � 3. ID “The Missing Children” � 4. Homework and Review
ADH Extension: How it is used in a criminal investigation. �Example 1 �A type of insect has a threshold temperature of 58 degrees F �On a day with a high temperature of 68 F and a low of 54 F, calculate the ADH available to its eggs received on the first day.
ADH Extension �What is known from the problem? �High Temp = 68 F Low Temp = 54 F �Threshold Temp = 58 F • What is the significance of this temp?
Solving the problem to find ADH � 1. Find the average daily temperature • Avg Temp = (68+54 F) / 2 = 61 F 2. Subtract the Threshold Temp from the Avg Temp 61 F – 58 F = 3 F This means that an average of 3 degrees of heat was available to the insect eggs. 3. Find the ADH = Temperature x Time 3 F x 24 hours ADH = 72 degree hours on the first day
Calculate the total Accumulated Degree Hours for the first two days �DAY 2 �High Temp = 76 F �Follow the steps! Low Temp = 52 F
Solution: Total ADH for 2 days �ADH for day 1 = 72 degree hours �ADH for day 2 = 144 degree hours • Avg Temp 64 F – Threshold of 58 F = 6 F • ADH day 2 = 6 F x 24 hours = 144 degree hours Total ADH = 72 deghours + 144 deghours = 216 degree hours What is the value of this data? What does it tell you?
ADH Sample Problem 2 �A body linked to a missing persons case has been discovered. Police are now investigating two possible suspects for murder. �You have been called in as the Forensic Entomologist to examine the body and assist the medical examiner.
�The body was found fully clothed on the first floor of a single family home. �You find maggots in the second instar stage on the body. �The temperature within the home was a constant 72 degrees F.
�The insect’s threshold temperature is 64 degrees F �Data you have on this species of fly is as follows • Minimum of 320 ADH to reach the second instar • Minimum of 480 ADH to reach the third instar How long has the body been in the home?
Solution �ADH = Temp x Time �Solve for Time = ADH / Temp � 72 F – 64 F = 8 F �Time = 320 deg-hours / 8 F = 40 hours �Time = 480 deg-hours / 8 F = 60 hours �Body has been in home 40 to 60 hours �How is this information used?
AGENDA Mar 4 �Learning Objective: Identify the procedures used to collect and preserve insects from a body. � 1. ADH Problem Solving � 2. Stages of Decomposition � 3. THE BODY FARM � 4. Homework and Review
THE BODY FARM �http: //www. youtube. com/watch? v=GCyicz Ac. RBY
AGENDA Mar 7 �Learning Objective: Identify the procedures used to collect and preserve insects from a body. � 1. The BODY FARM � 2. Stages of Decomposition � 3. Homework and Review • BODY FARM QUESTIONS
THE BODY FARM �http: //www. youtube. com/watch? v=GCyicz Ac. RBY
Question of the Day March 8 � Which of the following best describes the presence of blow flies on a dead body? � A. The victim has been dead for at least 2 weeks � B. The blow flies have been on the body for less than 1 hour � C. Time of death can be estimated between 1 day and 14 days � D. Time of death can be estimated between 1 week and 2 weeks
AGENDA Mar 8 �Learning Objective: Identify the procedures used to collect and preserve insects from a body. � 1. The BODY FARM QUESTIONS DUE � 2. Stages of Decomposition � 3. Homework and Review • QUIZ – Thursday • The Missing Children Questions and Summary �DUE THURSDAY
Decomposition of a Body � Insects will immediately colonize a body. • Bacteria, Fungi, and Animals • Environmental conditions • Some insects thrive in the sun vs. shady conditions � Also dependent upon stage of decomposition • Beetles will consume bone and cartilage � Stage of decomposition will affect species of insects present.
Stages of Decomposition � 1. Fresh Stage – Body and tissues fully intact • Blow flies, Ants � 2. Bloated Stage – putrefaction begins • Rove beetles and Carrion beetles � 3. Active Decay Stage • Maggots feed around natural orifices of body � 4. Advanced Decay Stage • Beetles � 5. Dry Stage • Centipedes, millipedes, cockroaches
Stages of Decomposition � 1. 4. � 2. 5. � 3.
Investigation and Collection of Insects from a Body � 1. Look at fauna and test soil to see if body has been moved. � 2. Collect specimens from different areas of the body, clothing, surrounding environment (indoor/outdoor) � 3. Collect 100 maggots � 4. Collect pupae from body, clothing, hair, soil � 5. Collect empty pupal cases from body, clothing, and surroundings
Investigation and Collection of Insects from a Body � 6. Collect adult flies � 7. Collect beetles � 8. Collect any other insects at scene � 9. Collect leaf litter near remains of body if outdoors (enough to fill a coffee can). � 10. Place all insects in vials with food
Labeling and Exclusions �Keep insects collected from different parts of the body separate from one another. �Insects would not be present if the body is wrapped in plastic, buried deep underground, and frozen or freezing temperature/conditions
AGENDA Mar 9 �Learning Objective: Apply forensic entomology to the solving of crimes. � 1. General Applications � 2. Homework and Review • ENTOMOLOGY QUIZ Thursday Mar 10 • Missing Children Worksheets DUE
General Applications �Detection of abuse in children �Neglect in the elderly �Automobile/Aircraft accident studies �Interpretation of blood spatterns �Determination of time of death �Recovery of human blood from digestive tract �Toxicological analysis
Accident and Criminal Investigations �Insects theorized to be within the top 20 causes of automobile accidents • What evidence would support this statement?
Accident and Criminal Investigations � Examination of remains of insects impacted and lodged onto front fascia, windshield, and radiator of automobiles. � � Yields evidence to the probable path of an automobile through particular areas • Pinpointing the location and areas of travel are of unique importance in some investigations
CONCEPT CHECK An elderly woman has been found dead in her second floor bedroom. Police suspect foul play. Victim discovered on Wednesday at 5 PM. Size and weight indicate larva have just entered third stage. House is temp controlled = average 20 deg C. Threshold Temp of blowflies is 12 degrees C. Minimum ADH to reach third larval stage = 780 degree – hours. Determine the approximate day and time of her death.
SOLUTION 20 points �Available energy 20 -12 deg C = 8 deg C �Solve for Time 780 deg-Hours / 8 deg C = 97. 5 hrs �Estimate TOD 97. 5 hrs = 4 days Victim died on Saturday at 5 PM
The MISSING CHILDREN � Forensic � Part 1 Entomology at Work � http: //www. youtube. com/watch? v=Tq. Kq 6 n. YK 9 m. A � Part 2 � https: //www. youtube. com/watch? v=0 S 9 oks 0 -rq. U � After watching part 2 of “The Missing Children”, write a brief summary to describe how Entomology was used to assist in solving this case. � Include specific details from the case and make connections with events presented in the video clips. WHAT WHEN WHERE HOW WHY
Slender Man Stabbings �http: //www. cnn. com/2014/06/04/justice/wis consin-stabbing/
Slender Man Stabbings �https: //www. youtube. com/watch? v=XQZz. J p. RWFCY
AGENDA Mar 10 �Learning Objective: Apply forensic entomology to determine time of death and criminal investigation. � 1. ENTOMOLOGY QUIZ � 2. Hand in Missing Children Homework � 3. Current Events � 4. Forensic Anthropology � 5. Homework and Review
The Body Farm - Decomposition �http: //www. youtube. com/watch? v=V_Siq. N D 9 b. NA �Decomposition of a Pig �http: //www. youtube. com/watch? v=R 1 CD 6 g Nmhr 0
AGENDA OCT 15 �Learning Objective: Examine the study of entomology and other forensic fields as they relate to the collection and analysis of evidence � 1. Homework and QUIZ Results � 2. The Body Farm • Complete Video Question Set � 3. Forensic Anthropology � 4. Homework and Review • STUDY YOUR NOTES
AGENDA OCT 16 �Learning Objective: Examine the study of anthropology and other forensic fields as they relate to the collection and analysis of evidence. � 1. Finish watching The Body Farm • Complete Video Question Set � 2. Introduction to Forensic Anthropology � 3. Homework and Review • STUDY YOUR NOTES
Forensic Anthropology � A forensic anthropologist can assist in the identification of deceased individuals whose remains are decomposed, burned, mutilated, or otherwise unrecognizable.
Forensic Anthropology �Forensic anthropology is the application of anthropology and human osteology in a legal setting, most often in criminal cases where the victim's remains are in the advanced stages of decomposition.
Applications � The analysis of skeletal, badly decomposed, or otherwise unidentified human remains is important in both legal and humanitarian contexts. � In addition to assisting in locating and recovering human skeletal remains, forensic anthropologists work to assess the following features from a skeleton. • the age, sex, ancestry, stature, and other unique characteristics.
The Bones Know � Bones offer amazing clues to the trained eye. � A trained forensic anthropologist can identify • disease or illness • pregnancy • possible career or profession of the deceased � Uses techniques preferred by archaeologists � It is also possible to determine other activities the deceased individual was involved with in life.
AGENDA OCT 19 �Learning Objective: Examine the study of anthropology and other forensic fields as they relate to the collection and analysis of evidence. � 1. Finish watching The Body Farm • Complete Video Question Set � 2. Introduction to Forensic Anthropology � 3. Homework and Review • STUDY YOUR NOTES
The Bones Know �Craniosacral measurements (skull measurements) have been established for all ages and race groups. �The skull features unique racial identifiers such as the length of jaw and the distance between eye sockets.
The Bones Know �The bones also hold clues to what work the person did. �Bony ridges form where the muscles attach and have pulled over the years. �What might a bony ridge on the wrist indicate about an individual?
DO NOW �Who is Baby Hope? �http: //video. foxnews. com/v/274164072500 1/baby-hope-detective-getsclosure/#sp=showclips&v=2741640725001
Question of the Day Oct 27 �A common racial identifier anthropologists can use to identify a victim is �A. the diameter of the eye sockets �B. the length of the jaw �C. the circumference of the skull �D. height of the cheekbones
DO NOW Forensics at Work �Part 1 �http: //www. youtube. com/watch? v=Wqkq. O Ejd 130 �Complete the question set.
FORENSICS at Wo. RK �Part 2 �http: //www. youtube. com/watch? v=OQj. Wc MF 5 Kx. Y
Question of the Day �A Forensic Odontologist can discover which of the following piece/s of information about a victim… �A. Time of death �B. Type of murder weapon used in a crime �C. Identification of a dead body �D. Identification of a suspect
OCT 15 DO NOW �Watch the following video clips. �http: //www. youtube. com/watch? v=RH 49 L 0 -YQj 0 �http: //edition. cnn. com/video/#/video/crime/ 2013/10/12/nr-lemon-conley-baby-hopedetails. cnn
DO NOW �http: //www. youtube. com/watch? v=i 9 Brtq 4 n LOM �Identity Solved? �http: //www. youtube. com/watch? v=WOx 7 sf p. ZGf. Q �Discovery �http: //www. youtube. com/watch? v=f. SWRm Om. Tsu. E
QUESTION of the Day �The acetabulum (notch where femurs sockets into hip) is �A. the same size in males and females �B. larger in females �C. larger in males �D. smaller in males
QUESTION of the DAY Oct 24 �A common sign of repeated abuse on skeletal remains is �A. bruising of tissue �B. fracture points on the bones of the extremities �C. Calcification of bones �D. Smooth areas around the joints and sockets.
The First Serial Killer �http: //www. youtube. com/watch? v=3 a. T 2 - n. WL 7 -0 �A&E Documentary �http: //www. youtube. com/watch? v=k. Bdq. MN ag. Ih. Q
The Bone Detective �Dr. Diane France, Forensic Anthropologist �http: //www. youtube. com/watch? v=Kcn. Gyb z. Fhj. M