Stories tagged forensic entomology

Did you ever wonder what those pesky moths ate before they ate your clothes in your closet? Clothes moths were known previously to feed on dead animals. Recently, scientists also discovered that the casemaking clothes moth, one of the two most common closet menaces, can be helpful in forensic work as well!

The casemaking clothes moth, so named because it makes a fuzzy case-like home for itself as a young caterpillar, will eat human hair and can even feed on corpses. The caterpillars can eat enough hair to identify a body with DNA.

These moths can be particularly helpful if a body is moved to a new location. The caterpillar will move to a nearby spot, away from the body, to make its cocoon. Then, if the body is moved, DNA evidence from the caterpillar in the cocoon can tie the victim to the original location.

More information on this can be found at Science News.

Tags : insects, csi, Moths, wool, forensics, entomology, forensic entomology

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Almost 50 years ago in Canada, a 14-year old boy was sentenced to death for the alleged murder of a 12-year old classmate. The 12-year old was found murdered two days after she was last seen with the 14-year old. Public opinion resulted in the boy being sentenced to life, due to what many thought was an improperly carried out investigation. Some of the evidence from this investigation included photographing and collecting some maggots from the body of the 12-year old. In 2000, the case was reopened.

Part of the research of the defense centers on the maggot evidence collected in 1959. In 2006, the corpses of three pigs were placed at the crime scene to collect additional maggot specimens. For those not in the know with regard to fly lifecycles, the development of a fly from egg to larva (maggot) to pupa to adult is tied to local environmental conditions, such as the temperature. Richard Merritt, a fly specialist from Michigan State University reviewed the specimens and environmental data. After examining the small size of the 1959 maggots, larval growth rates and the temperature, Merritt determined that there was no way that the boy could have committed the murder the day the girl disappeared (the boy had an alibi for the following day).

To check out some maggots in action on a pig corpse, check out Liza's pig cam log on Science Buzz pig!

http://www.smm.org/buzz/topics/forensic-entomology/lizas-pig-cam-log

Tags : entomology, forensic entomology, bugs, insects, Canada, maggots, death, time of death

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CSI: The Experience will open here at SMM on October 15.

One aspect of crime scene investigation is forensic entomology: the use of insects found on or near a body to help determine the time, manner, and location of death.

And we're fortunate that Valerie Cervenka, the first female board certified forensic entomologist, lives here in St. Paul. She's our Scientist on the Spot right now, so you can read about her work and get her answers to your questions.

And, Buzzketeers, do we have something "special" for you... Lots of forensic entomology studies are done using pigs, because (according to Jessica Snyder Sach's Corpse:

"The soft, near-hairless skin of a domestic pig closely duplicates that of a human, and that the torso of a luau-size porker parallels that of a 160-pound man."

Pig, @2pm, 9-18-08: Our pig, fresh from the freezer.
Courtesy Liza Pryor

That is, the skin, muscle/fat ratio, and other characteristics of pigs are reasonably good approximations of humans'. In death, what happens to a pig, and when, is pretty similar to what happens to human corpses. (If you think that's unpalatable, consider that the other way we can calibrate insect evidence is to do controlled studies at places like Tennessee's "Body Farm," where researchers observe what happens to people instead of pigs. You can search Buzz for the term "body farm" if you're interested in that: we've done a few stories.)

So we've obtained a young pig. (Don't worry: the pig died of natural causes.) And we've put it in a cage, with a webcam, and we're letting it decompose. The camera records a still image every 15 seconds, and we'll eventually turn all those photos into a time lapse, which Val Cervenka will help us interpret. Pretty cool. Pretty gross. And all in the interest of science.

Why didn't we wait for the exhibit? Well, insect activity slows dramatically or even drops off to nothing once the outside temperature gets to about 50 degrees. To follow the pig through most of its stages of decomposition, we had to get it going now.

Want to see what's going on with the decomposing pig right now? Click here. But don't say we didn't warn you. It's graphic.

Tags : stink, rot, pig cam, pig, maggots, forensics, forensic entomology, decomposition, decay, death

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