DETERMINING THE ANTIQUITY OF DOG ORIGINS: CANINE DOMESTICATION AS

289 Pages·2004·2.24 MB·English

DETERMINING THE ANTIQUITY OF DOG ORIGINS: CANINE
DOMESTICATION AS A MODEL FOR THE CONSILIENCE BETWEEN
MOLECULAR GENETICS AND ARCHAEOLOGY

A Dissertation

by

MICHELLE JEANETTE RAISOR

Submitted to the Office of Graduate Studies of
Texas A&M University
in partial fulfillment of the requirements for the degree of

DOCTOR OF PHILOSOPHY

August 2004

Major Subject: Anthropology
DETERMINING THE ANTIQUITY OF DOG ORIGINS: CANINE
DOMESTICATION AS A MODEL FOR THE CONSILIENCE BETWEEN
MOLECULAR GENETICS AND ARCHAEOLOGY

A Dissertation

by

MICHELLE JEANETTE RAISOR

Submitted to Texas A&M University
in partial fulfillment of the requirements
for the degree of

DOCTOR OF PHILOSOPHY

Approved as to style and content by:
_________________________ ______________________
D. Bruce Dickson D. Gentry Steele
(Chair of Committee) (Member)

__________________________ ______________________
Harry J. Shafer Lisa M. Howe
(Member) (Member)

___________________________
David L. Carlson
(Head of Department)

August 2004

Major Subject: Anthropology
iii
ABSTRACT

Determining the Antiquity of Dog Origins: Canine Domestication as a Model for the
Consilience between Molecular Genetics and Archaeology. (August 2004)
Michelle Jeanette Raisor, B.S, Texas A&M University;
M.A., Texas A&M University
Chair of Advisory Committee: Dr. D. Bruce Dickson

Archaeologists have favored a date of 14,000-15,000 years before present (BP)
for canine domestication. However, recent studies of mutations in the mitochondrial
DNA sequence by molecular geneticists have implied that dogs were domesticated over
100,000 years ago, which has challenged traditional theory. Geneticists have further
hypothesized that dogs originated from wolf ancestors based upon the number of
substitutions observed in dog and wolf haplotypes. Although both disciplines provide
substantial evidence for their theories, the origin of dog domestication remains
controversial. Several areas continue to be debatable. First, both geneticists and
archaeologists incorrectly use the term domestication to describe events that clearly can
not be proven to under human control. Second, the evolutionary development of canines
is viewed by molecular biologists as well as archaeologist to be indicators of
domestication without any further exploration of other probable causes. Third, the
studies in canine genetics are so complex that most archaeologists have difficulty in
providing evidence that would be contradictory to molecular theory. Fourth, both fields
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of study continually ignore innate behavioral characteristics of wolves that would make
domestication highly improbable. Fifth, geneticists rely heavily on data gathered from
sequencing of mitochondrial DNA, which has been assumed to maternally inherited.
However recent human studies have shown that this assumption has now been proven to
be incorrect. And finally, not only are morphological traits of fossilized dogs and wolves
so similar that making a taxonomic identification improbable, but also the amount of
archaeological remains available are too sparse and fragmented for accurate affiliation.
An alternate theory of canine domestication will be proposed utilizing data
gathered from the archaeological record and molecular research. I hypothesize that dogs
diverged naturally from wolves 100,000 years ago as a result of the natural course of
evolution, not human intervention, and had already evolved into a dog prior to being
domesticated by humans 14,000-15,000 years ago. Evidence will be presented to clearly
show that this hypothesis is a more accurate scenario of canine domestication.
v
ACKNOWLEDGEMENTS

This dissertation would not have been possible without the assistance of several
people. I am especially indebted to Dr. D. Bruce Dickson, my committee chairman, who
gave unselfishly of his time. His continued encouragement and interest made this project
possible. His willingness to share his expertise added considerably to my knowledge of
archaeology and kept me focused.
I would also like to thank Dr. D. Gentry Steele for his continuing support,
interest and for his many kindnesses extended to me while I was a graduate student. As
both a professional anthropologist and friend, he became my mentor, for which I will
always be especially grateful.
I want to extend my thanks to my friend Dr. James N. Rugila, DVM. He not only
spent an enormous amount of time taking care of my ailing dogs, but also his expertise
in molecular genetics and physiology was more help than he will ever know. He was
very patient with my endless questions.
Finally, I wish to thank my parents Harry and JoAnn Raisor for their
encouragement and for raising me to persist despite any obstacle.
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TABLE OF CONTENTS
Page
ABSTRACT.............................................................................................................. iii
ACKNOWLEDGEMENTS...................................................................................... v
TABLE OF CONTENTS.......................................................................................... vi
LIST OF FIGURES................................................................................................... ix
LIST OF TABLES.................................................................................................... xi
CHAPTER

I INTRODUCTION...................................................................................... 1

II BASICS OF MOLECULAR GENETICS................................................... 9

What is DNA?................................................................................... 9
What is a gene?................................................................................. 13
What is a mitochondrial DNA?......................................................... 14
Mitochondrial inheritance................................................................. 16
What is a microsatellite?................................................................... 17
Nuclear and mitochondrial size......................................................... 17
What is PCR?.................................................................................... 19
Development of the canine genetic map........................................... 20
Organization of the canine genetic map............................................ 27
Microsatellites as genetic markers.................................................... 29
Evolutionary relationships of canids................................................. 31
Molecular evolution of canids........................................................... 36
Timing of genetic divergence............................................................ 41
Phylogenetic tree of the dog and wolf............................................... 43
Ethiopian wolf................................................................................... 62
Coyote............................................................................................... 64
Red wolf............................................................................................ 67
Jackals............................................................................................... 75
Variability of wild-type dog breeds.................................................. 77
Genetic variability of primitive dog breeds....................................... 79
Australian dingo................................................................... 79
New Guinea Singing dog..................................................... 84
Carolina dogs....................................................................... 86
vii
CHAPTER Page
III BEHAVIOR OF WOLVES....................................................................... 88
Reproductive development................................................................ 89
Neonatal development....................................................................... 89
Behavioral development.................................................................... 91
Facial expressions............................................................................. 101
Instinctual vs. cognitive processing.................................................. 104

IV THE ARCHAEOLOGICAL RECORD..................................................... 112
The complicated process of domestication....................................... 113
Morphometric differences in the skeletal remains
of dog and wolf................................................................................. 128
The fossil record of Canis familiaris................................................. 144
North America....................................................................... 145
Meso America and South America....................................... 157
Greenland.............................................................................. 158
Great Britain.......................................................................... 160
Germany................................................................................ 163
France.................................................................................... 166
Ireland.................................................................................... 168
Sweden and Denmark............................................................ 169
Hungary................................................................................. 169
Iraq........................................................................................ 171
Russia.................................................................................... 172
Armenia................................................................................. 174
Israel...................................................................................... 175
Africa..................................................................................... 178
Egypt..................................................................................... 178
Kazakhstan............................................................................ 179
Thailand................................................................................. 181
Australia................................................................................ 183
Japan...................................................................................... 183
Siberia.................................................................................... 185
China..................................................................................... 187

V DISCUSSION............................................................................................. 191
Problems with mtDNA inheritance....................................... 191
Potential limitations of DNA sequencing.............................. 201
Some new alternative methods.............................................. 207
viii
CHAPTER Page

Limitations of current molecular studies............................... 212
Contributions of animal behavior studies to the
understanding of dog domestication..................................... 223
Limitations of the archaeological record............................... 233

VI CONCLUSION........................................................................................... 238

Domestication of the Dog: An Alternative Hypothesis.................... 238

LITERATURE CITED............................................................................................. 257

APPENDIX: THE AUTHOR'S ENGLISH SETTERS............................................ 276

VITA ........................................................................................................................ 278
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LIST OF FIGURES

FIGURE Page

1 Over 400 varieties exist today, ranging in size, shape and color.................. 10
2 Modern breeds of dogs exhibit many differences in head shapes................. 11
3 Mastiff-like breeds were depicted on Egyptian tombs, similar
to the mastiff above....................................................................................... 12

4 Canine mitochondrion, complete genome..................................................... 15
5 Labrador retrievers have been used to study the genetic inheritance of
narcolepsy. .................................................................................................... 25

6 Four phylogenetic divisions proposed by Wayne and Ostrander (1999)
based upon DNA analysis............................................................................. 38

7 Composite family tree of canids. ................................................................. 39
8 Neighboring-joining tree of wolf and dog haplotypes based on
261 bp of control region sequence. .............................................................. 46

9 Haplotypes found in East Asia, Europe, and Southwest Asia are
indicated in separate networks with orange, blue, and green........................ 50

10 Siberian Husky.............................................................................................. 52
11 Hairless breeds of dogs from top left to bottom, Chinese crested,
Xoloitzcuintli (Mexican hairless), and Peruvian Inca Orchid....................... 53

12 Coyote (Canis latrans).................................................................................. 64
13 Red wolf (Canis rufus).................................................................................. 68
14 Australian dingo, Canis lupus dingo............................................................. 80
15 Examples of primitive dogs........................................................................... 83
16 Wolf pups are born blind and deaf with limited motor ability...................... 90
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FIGURE Page

17 Socialized wolves will become more bold and assertive as they
become more confident with their experimenters, sometimes
leading to a full blown attack. ...................................................................... 100

18 Various behavioral tests have shown that wolves are unable to
skillfully interpret human social cues, facial expressions and lack
the ability to have face/eye contact with humans.......................................... 111

19 After multiple generations, tame foxes began exhibiting changes in
coat texture and color such as piebald spotting. ........................................... 124

20 Elements comprising the canid skull and mandible of a
modern wolf, Canis lupis. ............................................................................ 130

21 The skulls of a 43 kg wolf (left) and a 43 kg dog (right).............................. 133
22 Skull and mandible of a domestic dog, Canis familiaris. ........................... 135
23 Comparison of skulls of present-day wolf, late Paleolithic wolf, and late
Paleolithic short-faced wolf.......................................................................... 138

24 A mitochondrial mutation may have led to selective replication of
paternally derived DNA (green) in muscle. ................................................ 194

25 Egyptian artists often depicted dogs resembling the
present day Pharaoh hound. ......................................................................... 237