Thursday, February 27, 2014

Dogs in Medieval Coats of Arms

Now that I've posted dogs in medieval manuscripts and tapestries, I'm finishing  up with dogs in coats of arms.  Greyhounds are the most common breed featured in family crests, especially in England and France.

This family crest appears on the back of a diptych of a portrait of Phillipe de Croy, about 1460.
Koninklijk Museum

The animals on either side of the shield hold and guard it.
The Tudor Family coats of arms - protected by a Greyhound and dragon.
About 1428

A dog represents the loyalty of the master, so I'm not sure what's going on here.

For historians, a family crest can indicate what extinct breeds looked like. 
Below is a short-legged Talbot Hound.

Carter of Castle Martin Crest

The short-legged Talbot may be the ancestor of
the Basset Hound.

It's possible that the word Talbot was a sort of generic term for
any white scent hound.The  dogs in the crest below are also
called Talbot Hounds, but they have long legs.

The St. Hubert's Hound, also extinct, may have been a type of Talbot. Historians claim that the St. Hubert is the direct ancestor of Bloodhounds and other scenting types. The breed disappeared at the end of the 18th century.

The breed has symbolic meaning, as does the collar.  
Collars shaped like crowns indicate a family's nobility.

Collar that is not crown-shaped.

This looks like a collar shaped like a crown.
(Arms of Henry VII)

Monday, February 17, 2014

Are Pedigreed Dogs Unhealthy?

The answer is some are. And this is one reason:

I came up with this analogy to explain how the canine genome has been compromised as a result of modern breeding practices. I think about this stuff a lot because I write about canine genetics and I'm always looking for ways to simplify complex topics.
The fragile purebred canine genome

Like pulled-thread needlework, where the pattern is created by removing threads from the warp and weft of a piece of even weave fabric, traits that define purebred dogs are created by removing genetic variations that breeders find undesirable.
Think of this as the generic dog genome
 All traits are here, some hiding and some expressed.
Traits removed by breeders might be anything from kill-instinct to black spots on a white coat. Some genes are completely wiped away and cannot be reclaimed within the breed.

Rigorous selection is the pulled thread that defines purebred dogs.  
Beautiful? Yes.

But the integrity of the fabric can be undermined and weakened as a result. In purebred dogs, a few genes may control multiple traits. Pull one thread and out comes another, perhaps unintentionally.   For instance, in the Dalmatian, when breeders selected for coats with fewer spots, they were eliminating the genetic variants that not only control pigment, but are also responsible for building parts of the ear.  As a result, they inadvertently created a population of deaf Dals.
In Dalmatians, removing spots may also remove genetic variants responsible for ear development.

Although it doesn't fit with my pulled-thread analogy, adding or emphasizing traits can magnify unwanted genetic variants that might be related to diseases.

Too much of a "good" thing?  Scientists have identified a relationship
between skin wrinkling and Shar Pei Fever

And finally, the genome is not static. Fragile purebred genomes can be further undermined by random mutations. Genetically diverse breeds don't suffer as much, because they are better able to compensate.

The good news is that dogs with genetic issues can be out bred to similar breeds.  The genetic variants that cause the flaws are not eliminated, but they are diluted, meaning the chance of showing up as traits is significantly reduced. For instance, Dalmatians bred to Pointers for several generations and then bred back to Dals are much healthier than their purebred counterparts. But like everything else with purebred dogs, it's controversial.
Dalmatian-Pointer back crossing reintroduces healthy genes, eliminating many painful diseases that Dals suffer from.

Friday, February 14, 2014

Cross-species Valentines Day Tribute-

Roses are red, Violets are blue, We love our dogs, How about you...

Quadrupeds: (left to right) Grace, Angel, Buster, Sumo
Bipeds: Charles and Carol
Chance and Chumley
Sadie and a smitten Christy

Crista and Paige

Rod and Gus
Twins seperated at birth - Deb and Ruby

Jake and his boy Allen - meant for each other
Cecelia and Daisy

Matt and Buddy

Gizmo and his pets, Elaine and Rev
Dot and Babs

Max and Tom

Laurie and Chloe
Rocco and Debbie

Mr. Toad and his person, Bronwyn
Sue and Sara
Lisa and Zen

Friday, February 7, 2014

Peruvian Mummy Dogs

Multiple thousands of ancient dog burials, some going as far back as twenty plus thousands years, have been discovered on every major global land mass.

Iron age dog burial, Thailand

In some places dog burials are so common, that their absence prompts scientists to ask, "Why are no dogs buried here?"
The most recognized archaeological sites where dogs are buried

Why humans buried dogs isn't  clear. Some were sacrificed for ritual, others disposed of for sanitary reasons, and many lovingly interred out of respect and affection.

One of more than 40 mummified dogs discovered in Peru in 2006

Two recent discoveries in Peru support the idea that in some parts of the world, dogs were part of the family. When people died, it was customary to kill their dog and send both souls to wherever souls go. As Will Rogers said: "If there are no dogs in heaven, then when I die I want to go where they went."  In 2006, in Peru, archaeologist Sonia Guillen reported that her team had discovered around 40 dogs buried 1000 years ago in separate plots alongside their owners.The discovery was unusual in that dogs were buried with items that looked like toys and dog food.

Guillen, who studies Chiribaya culture, told the press, “We have found that in all the cemeteries, always, in between the human tombs there are others dedicated to the dogs, full-grown and puppies. They have their own graves, and in some cases they are buried with blankets and food."  She added that today, Chiribaya people prize their dogs for their llama herding skills, and Guillen suspects that the mummified dogs were much loved companions.  In addition, they may be direct ancestors to dogs that populate the village today.  
Peruvian village dog

In 2013, on the heels of Guillen's find, archaeologists unearthed the remains of 137 dogs, from puppy to adult, buried more than 900 years ago, in Lima, Peru.  The dogs were placed in resting positions alongside human remains. Some were wrapped in mummy bundles, along with vegetable rope.  Watch this video.

Dogs from both digs were under 30 pounds, with long yellow coats, very similar to the dogs still used to herd llama today.