Monday, September 7, 2015


You have probably heard of search-and-rescue (SAR) dogs, and of cadaver dogs.  And maybe you have even heard of Human Remains Detection (HRD) dogs, which are sort of like cadaver dogs, but not exactly, because HRD dogs help with crime scenes, old cases, and stuff like that.  Cadaver dogs are more dogs who find people who got killed in natural disasters or because they drowned in the lake or got lost in the woods.

But now there is a new kind of job that dogs do, and it is called Historical Human Remains Detection (HHRD).  This job is so new and so specialized that only about 18 dogs in the whole world have been certified so far to do it.  The difference between an HRD dog and an HHRD dog is that the first kind of dog is looking for residual scent, small scent sources, and old cases where maybe a body has been buried or hidden for a few months or years.  The HRD dogs learn to ignore any kind of fresh human scent or any animal scent.

The historical human remains detection dog, however, is trying to find where human bodies decomposed a really long time ago, like 100 years or even more.  Another name for these dogs is historical grave detection dogs.  Sometimes the grave is so old that there are only tiny fragments of the body, but what the dog is detecting is the odor of decomposition that was left in the soil when a body used to be there.

I would just like to mention, at this point, that the human nose has about 5 million olfactory cells, and the canine nose has about 220 million.  Also, almost one-eighth of the brain of a dog is devoted to processing olfactory input.  Everyone, dog and human, should remember this very important information because it explains why dogs are able to do some of the spectacular things they do, such as finding 100-year old grave sites.

Dogs can be trained to do different types of scent work, but they work in different ways according to the job they are doing.  A dog who is sniffing the air for the scent of a live human will hold his head up.  But a dog who is looking for old graves, old bone, and teeth will work slowly, with its nose close to the ground because these types of scents tend to be found only on the surface of ground and not in the air.

The best conditions for working a detection dog are temperatures between 40ºF and 75ºF, with moist ground, high humidity, and a light breeze.  Dogs can work in more extreme conditions such as high heat or snow, but the working time will be decreased.  Prehistoric graves are the most fragile and difficult scents for dogs to find, so the dogs need frequent rest and water breaks.

Legend, a Belgian Malinois trained as an HHRD dog.

It can take as long as two or three years to train dogs for this type of work.  Many of them start training as puppies, imprinting on the scent of human bones at a very young age.  The best dogs for the job seem to be those with longer noses, because that means they have lots of smell receptors.  Also, they have to have a strong work ethic and a huge desire to please.  The Institute for Canine Forensics, in Woodside, California, trains many dogs for HHRD work.

Detection dogs are trained by rewarding them for finding the right types of remains.  They learn to "alert" by sitting or lying down when they find the scent.  They are taught to ignore anything else, such as animal remains.  As training goes on, the job of finding the human remains is made more difficult until the dog alerts even on very small amounts or fragments, such as a tooth or bit of bone.  The HHRD dogs, just like HRD dogs, are taught never to pick up or dig up the remains.  Everything has to be preserved just the way it was found.

HHRD dogs learn to work an area with a handler, in a methodic grid pattern.  Humans sometimes think that remains and artifacts must be in a certain location, but dogs don't know that, so they are free to figure out where these items really are, just by using their sense of smell.
The findings made by this type of search dog can be extremely useful to archeologists.  Examples of searches done by HHRD dogs include finding the boundaries of poorly marked cemeteries, locating lost graves or cemeteries, and finding scattered bones or artifacts related to burial.  Groups that have requested dogs to do searches include archeologists, American Indian tribes, cultural resource management firms, construction companies, cemetery preservation foundations, and families wanting to find lost family cemeteries.

So once again, dogs have proven themselves to be extremely clever and useful to people.  Probably, we will see more and more HHRD dogs in use in the future.  However, we will probably not see chihuahuas doing this job because (1) a lot of chihuahuas have short noses, and (2) not many chis are so eager to please that they will go out in all kinds of weather to sniff around all over the ground for people who have been dead for centuries already!

1 comment:


    Those who claim they were saved by "faith alone" like to quote Hebrews 11:7 to prove they were by "faith only," just like Noah.

    Hebrews 11:7 By faith Noah, being divinely warned of things not seen, moved with godly fear, prepared an ark for saving of his household, by which he condemned the world and became heir of righteousness which is according to faith.(NKJV)

    Hebrews 11:7By faith Noah, being warned by God about things not yet seen, in reverence prepared an ark for the salvation of his household, by which he condemned the world, and became an heir of the righteousness which is according to faith.(NASB)

    Noah was not saved the minute he had faith, he was saved and became an heir of righteousness after faith plus preparing the ark.

    Noah was saved by faith plus obedience, not by faith alone.
    He was obedient by preparing the ark for saving his household. If Noah had tried being saved by "faith alone" he would have drown just like the rest of the world.

    1 Peter 3:20.....God waited in the days of Noah, while the ark was being prepared in which a few, that is, eight souls, were saved through water.(NKJV)

    Noah was not saved on dry land by "faith alone." He was saved by faith plus obedience.

    Without faith Noah and his household would not have been saved.

    Without Noah building the ark, Noah and his household would not have been saved.

    Faith plus obedience saved Noah and his household.

    Faith only advocates claim they are saved by "faith only." They reject being immersed in water in order to be saved.

    Jesus said faith plus obedience saves. Mark 16:16 "He who believes and is baptized will be saved....(NKJV)

    Noah was not saved until he built the ark and men today are not saved until they are immersed in water.

    Noah would have drown without the ark

    Men today will drown in their sins without being baptized into Christ for the forgiveness of their sins. Mark 16:16, Acts 2:38. Acts 22:16, 1 Peter 3:21, John 3:5, Romans 6:3-7, Ephesians 5:25-27, Colossians 2:12-13 and Galatians 3:27.