Dog Breeds, Types & Classes
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Dog Breeds, Types & Classes Published by the Dublin society for the prevention of cruelty to animals www.dspca.ie All rights reserved. No part of this publication may be reproduced, distributed, or transmitted in any form or by any means, including photocopying, recording, or other electronic or mechanical methods, without the prior written permission of the publisher, except in the case of brief quotations embodied in critical reviews and certain other noncommercial uses permitted by copyright law. For permission requests, write to the publisher, addressed “Attention: Permissions Coordinator,” at the address below. The majority of images have been purchased from Bigstock: Stock Photos & Vector Art, for use within course material and not merchandising or branding activities. Those images that have not been acquired from Bigstock, have been acquired under various commons licenses which are specified per image in the list of figures, or independently created by the author. First printing, September 2018 Contents Introduction Types Hunters Herders Mastiff-Like Wolf-Like Making Use of the Genetics Dogs with Jobs Class Gundogs Hound Pastoral Terrier Toy Working Breeds Pros of Breed Standards Cons of Breed Standards Rhodesian Ridgeback Cavalier King Charles Spaniel Pug Siberian Husky Lhasa Apso Border Collie Cross Breeds Bibliography Introduction One of the first questions a dog owner typically gets asked is "What breed is she?" or “What’s he crossed w i t h ?". It has become such a defining feature in modern society that even our crossbreeds have specific names. Dogs have been developed for an astounding number of reasons down through the centuries with many of those purposes lost to history. Some d o g s are bred f o r a specific job or function, some for their behavior, and others still for their appearance. All domestic animals come in different types or breeds to fill some specific requirement we have of them. The differences between b r e e d s a r e not great enough to define separate species, considering that the term species is defined as a group of animals, (or organisms in general), wherein members of different breeds or types, ( formally known as hybrids), can successfully breed with t h e i r offspring also capable of reproduction. Dogs are clearly capable of successful breeding between breeds, however, successful mating can occur between dogs and wolves, so should they be considered as the same species, or merely of the same family. These are questions best left to experts in genetics and zoology but should still be considered for developing our understanding of dogs. In this course, we consider dogs and wolves to be of separate species, and all dogs of the one species. We discuss the difference between types, classes and breeds. However, it should be noted that the notions of types and classes are not clearly defined and a generally accepted definition should not be assumed. Clearly, no one specific breed of dog is generally superior over another as there are different metrics on which such an award would be considered. Appearance is clearly a subjective matter; how different people view beauty is not just varied but also time dependent. Health is an important factor which can vary significantly within breeds, depending on breeder standards or genetic mutations that build up within a small breeding population. Therefore, the health of an overall breed can change w i t h i n a few generations. Utility or the usefulness of a dog is debatable as a metric. There is no doubt that medical alert dogs are vital for the people whose lives depend on them however many people w o u l d argue t h a t the mere companionship of a dog is sufficient to justify its utility. This module looks at the evolution of breeds, what got the whole thing started in the first place, and the ethical implications of breeds. It is not the purpose of this module to list all dog breeds, to advocate any one particular type of dog over another, or take a stance on morality of breeds in general. Types As we mentioned briefly before, dog evolution likely started with an initial self-selection for tameness w h i c h led to a mutually beneficial relationship between humans and those early d o g s . When h u m a n s did get involved in the process it was to naively preference dogs that suited a particular job best. In this portion of the development of dogs there was likely only a partially deliberate manipulation of breeding habits but was most probably more of a case of isolation of the different behavioural attributes. Of course, as time went on this led to direct selective breeding for features. While there are a multitude of different breed categories acknowledged by different organisations today1, initially 1 More on this later in the module dogs were categorised by their utility. Within each form of utility, different characteristics were given preference to narrow the speciality of each type of dog. A long term study led by a number of leading institutions2, culminating 2 in a large open database, CanMap. This database mapped the canine Kerstin Lindblad-Toh, Claire M Wade, Tarjei S Mikkelsen, Elinor K genome across 85 genetically distinct breeds of dogs, using five to ten Karlsson, David B Jaffe, Michael Kamal, unrelated specimens to source the data. This project not only resulted in Michele Clamp, Jean L Chang, Edward a database but also a myriad of studies analysing the data with many J Kulbokas, Michael C Zody, et al. identifying a number of specific genes that impact the study of disease in Genome sequence, comparative analysis humans. and haplotype structure of the domestic dog. Nature, 438 (7069):803–819, 2005. The study identified four specific genetically-based types of dog that we have bred for. These were: • hunters • herders • Mastiff-like • wolf-like Of the 85 different breeds a n a l y s e d , each was ma d e up of some proportion of each of those four types. In some cases, the breed was almost completely made up of one type, in others there was a generous proportion of some or all types. This shows us that as the different types w e r e perfected n e w l y developed components or attributes in other types were integrated to make use of some key feature. This is best described in Figure 1 below. Hunters There a r e little to no ’ancient’ breeds in this group. Typically, these dogs have been developed relatively recently. There are representations Figure 1: Proportion of dog types per breed for 85 genetically dis- tinct breeds for which between five and ten unrelated dogs were sampled. Wolf-like, Mastiff- like , Herders , and Hunters . of some purportedly ancient breeds in this group however that likely points to a recreation of an ancient breed from visually similar dogs rather than showing a direct link to those ancient representations. While they were likely bred for hunting it would be expected that they would have gene identification more similar to those in the wolf-like category to define their supposed ancient status. Herders Those dogs typical to the herding category are familiar to most. The collie and the Shetland sheepdog naturally make a strong appearance in this group. Just as with the hunting group, however, there are several entries in these categories that would not traditionally be known for herding, the whippet and the pug b e i n g p r i m e examples. Also, as with the outliers from the hunting group, this likely demonstrates the use of appealing characteristics of one type being selectively used to emphasise an existing trait in another or develop a new type from multiple type sources. Mastiff-Like This type cover quite a few different breeds but all boil down to a specific origin, that is defence, gua rdi ng or intimidation. Typically, these are large, stocky breeds. The large contribution of these genetics to, for example, the Bulldog accounts for its stoutness, h o w e v e r its height is more l i k e l y a result of manipulating size of descendants via focused selection f o r size rather than the attempted i n c l u s i o n of smaller types, such as terriers. While the German shepherd is a much slighter and n i m b l e animal than the Newfoundland its genetic proportions mirror, it is the nature of type that was taken rather than appearance. Wolf-Like Those breeds with a heavy component of wolf-like genetic material are much closer to their wolf ancestors than any other breeds. This signifies a retention of many of the qualities of the original or at least early domestications of wolves and hence indicates much older breeds than those with a smaller wolf-like component. As with the other groupings, not all of those dogs in this category immediately make intuitive sense. The chow chow, for example is not the first breed one would think of to be more closely related to the wolf than the German shepherd, for instance, however its supposed origin as a potential food source may reflect its age as being fr o m a time when p eo p l e were as yet unsure what to make of dogs. Making Use of the Genetics Another significant contribution of the CanMap project was to allow scientists a glimpse into a simplified genetic story. Typically, in most animals including ourselves, the genetic sequence that influences tiny changes is extremely large, so much so that it makes understanding the contributing factors to those differences very difficult.