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Scavenging hypothesis: Lack of evidence for dog domestication on the waste dump

Authors:

Abstract

In the debate on canine domestication, researchers have identified a lot of valid information regarding the time, the region and the ancestor of the dog. But researchers are still figuring out, why and how this process started. The scavenging hypothesis, first proposed 2001 by Ray and Lorna Coppinger, proclaims the first human waste dumps as the ecological niche for the self-domestication-process of dogs. Many scientists refer to that model, sometimes partly modified. The scavenging hypothesis is broadcasted by most public media as the commonly accepted model of dog's domestication. Thus, we have to deal with that popular model. Based on a broad multi-disciplinary approach like human evolution, archaeology, palaeogenetics, psychology and neurobiology, we will look for evidence. Investigating nine assumptions of the scavenging hypothesis we did not find any evidence. Dog's domestication started thousands of years before the advent of food waste dumps. The scavenging hypothesis cannot explain why only wolves and never foxes nor jackals have been domesticated. Paleolithic people and ancient wolves were living together closely in the same ecological niche hunting the same prey with the same cooperative methods. It is likely that they met very often and knew each other very well. We have some hints, that ancient wolves and people treated each other with respect cooperatively. We have hints for an active cooperation from humans and dogs starting in the Upper Paleolithic period long before it would have even been possible scavenging human waste. We have hints for emotional bonds between ancient people and dogs. Emotional bonds would have been unlikely for an animal hanging around human settlements while scavenging carrion and feces, like the scavenging hypothesizes describe. Looking at recent dogs and humans we have evidence for strong unique similarities in the psychological and neurobiological structures eventually allowing interspecific bonding, communication and working. Interspecific cooperation decreased the level of the stress axis of both species in the Paleolithic period and even does so today, what improves our social and cognitive abilities. We propose that dogs domestication could be understand as an active social process of both sides. Further investigations need a closely networked multidisciplinary approach.
Scavenging Hypothesis: Lack of evidence
for Dog Domestication on the Waste Dump
Christoph Jung1, Daniela Pörtl2
1 Petwatch, Halle, Germany,
2 Psychiatric department, Saale-Unstrut Klinikum, teaching hospital Leipzig and Jena Universities,
Naumburg, Germany
Abstract: In the debate on canine domestication, researchers have identied a lot of valid information regarding the
time, the region and the ancestor of the dog. But researchers are still guring out, why and how this process started.
e scavenging hypothesis, rst proposed 2001 by Ray and Lorna Coppinger, proclaims the rst human waste dumps
as the ecological niche for the self-domestication-process of dogs. Many scientists refer to that model, sometimes
partly modied. e scavenging hypothesis is broadcasted by most public media as the commonly accepted model of
dog’s domestication. us, we have to deal with that popular model. Based on a broad multi-disciplinary approach like
human evolution, archaeology, palaeogenetics, psychology and neurobiology, we will look for evidence. Investigating
nine assumptions of the scavenging hypothesis we did not nd any evidence. Dog’s domestication started thousands
of years before the advent of food waste dumps. e scavenging hypothesis cannot explain why only wolves and never
foxes nor jackals have been domesticated. Paleolithic people and ancient wolves were living together closely in the
same ecological niche hunting the same prey with the same cooperative methods. It is likely that they met very oen
and knew each other very well. We have some hints, that ancient wolves and people treated each other with respect
cooperatively. We have hints for an active cooperation from humans and dogs starting in the Upper Paleolithic period
long before it would have even been possible scavenging human waste. We have hints for emotional bonds between
ancient people and dogs. Emotional bonds would have been unlikely for an animal hanging around human settlements
while scavenging carrion and feces, like the scavenging hypothesizes describe. Looking at recent dogs and humans we
have evidence for strong unique similarities in the psychological and neurobiological structures eventually allowing
interspecic bonding, communication and working. Interspecic cooperation decreased the level of the stress axis of
both species in the Paleolithic period and even does so today, what improves our social and cognitive abilities. We
propose that dogs domestication could be understand as an active social process of both sides. Further investigations
need a closely networked multidisciplinary approach.
Key Words: dog, wolf, domestication; scavenging hypothesis; stress-axis; coevolution.
* Corresponding Author: jung@petwatch.de
Introduction
Dogs (Canis lupus familiaris) are called our best friends. ey are living in close proximity
with us round over the world in quite all cultures during each historical period. But it is still an
open question, how and why dog derived. Ray and Lorna Coppinger proposed a process of self-
domestication as scavengers on the rst human waste dumps (Coppinger & Coppinger, 2001;
2016). ey observed recent dog populations in special ecological niches like on Pemba Island
(Tanzania) or on the Mexico City waste dump. ose dogs are living primarily on and from
human waste. Coppingers argue, that those dogs would be the original dog type. When hu-
man started the epoch of agriculture and permanent settlement, they produced rst food waste
dumps. ese dumps have been a new ecological niche for wolves (Canis lupus). While scav-
enging and hanging around on the dumps, wolves with a temperament allowing them to ap-
proach humans showed higher reproductive success. Over the time specimens more tolerant to
humans have been selected naturally. us, dog should have been derived. Many scientists refer
to that hypothesis in their papers and even public media like BBC (2011) or New York Times
(2017) are broadcasting this version. erefore, it is worth looking for evidence supporting that
popular model.
Dog Behavior, 2-2018, pp. 41-56
doi 10.4454/db.v4i2.73
Submitted, 03/07/2018
Accepted, 07/08/2018
In the early two thousands dogs were making a comeback in science. Especially in the last
years, a lot of valid research from several disciplines e.g. human evolution, archaeology, paleo-
zoology, palaeogenetics, biology, psychology and particularly neurobiology has been published,
providing hints and evidence for a better insight to understand how dog evolved. us search-
ing for evidence of the scavenging hypothesis, we have to take a multi-disciplinary point of
view. First, we will explore nine basic assumptions of this special dog domestication model.
1. The time range dog domestication started
e scavenging model envisages dogs coming up around 8,000 years ago (Coppinger, 2016,
p.220), when human started the epoch of agriculture and permanent settlement in the region of
the Fertile Crescent. ose human settlements produced rst food waste dumps, which should
have provided the new ecological niche where dog derived from wolf. However, there is clear
evidence of much older dogs, pushing their origin back into an epoch at least 15,000 years ago
when our ancestors were still hunting and gathering (Botiqué et al., 2017; almann et al., 2013;
Ovodov et al., 2011). Today it is commonly accepted, that dog derived in the Paleolithic period,
thousands of years before the epoch of settled agriculture started, perhaps more than once, but
especially in the area of the former Eurasian cold steppe, where we found the most remains of
early dogs or protodogs, advent of agriculture started at rst thousands of years later. As com-
monly accepted dog-remains in that region are much older (Germonpré et al., 2009, 2015; Losey
et al., 2013; Janssens et al., 2018).
2. Paleolithic people did not produce food waste dumps
e Paleolithic Homo sapiens did not build any slaughter or kitchen dumps (Havlícek, 2015;
Havlícek & Kuca, 2017). Even when they lived as nomads with regularly summer and winter
camps they did not produce any dumps containing food. Nevertheless, it is quite unlikely, that
butchering place and camping place have been at the same site. Butchering places were sepa-
rated. ey did not want to alert predators to their camps and they could not shoulder a killed
mammoth. Nevertheless, our ancestors sometimes had a problem with waste. Archeologists
describe four dump types during the Paleolithic period:
a) Archeologists have found several stone tool factories with a lot of stone tool waste (Havlícek,
2015; Rust, 1948).
b) In some caves burned bone dumps have been found (Jelínek, 1977; Boscha, 2012).
c) And archeologists have found a lot of shell midden which did not have any potential benet
neither as construction material nor as fuel and surely not as wolf-food (Gutiérrez-Zugasti et
al., 2011; Havlícek, 2015).
d) Archeologists even found mammoth-bone accumulations, but without any tracks of bites
from wolves or dogs. ese mammoth-bone dumps served as a store of construction material
or fuel (Boscha, 2012). In the cold steppe there was not enough construction- or rewood.
us bones, fat and quite all other remains of the prey were used in daily life.
In sum Paleolithic people used the entirety of the carcasses for eating, clothing, warming or
as tools or fuel. First waste dumps regularly containing food rst appeared in the Neolithic pe-
riod.
3. And never enough
Coppingers schedules the new ecological niche starting with the advent of settled agricul-
ture. Other scholars, promoting this model, are pushing the timeline back to the period of
hunters and gatherers. “First a founder group of less-fearful wolves would have been pulled
42
43
toward nomadic encampments to scavenge kills or perhaps salvage wounded escapees from
the hunt.” (Driscoll et al. 2009) But, even if nomadic hunters might have temporarily produced
food remains, it could never have been enough to feed a founder group of wolves. Paleolithic
hunter clans consisted only of 20 to 50 individuals (Groeneveld, 2016). Nomadic hunters in the
Eurasian cold steppe were permanently following the big herds of bovids or mammoths (Am-
kreutz et al., 2018). Even if they lived in temporarily camps producing food waste, it would have
been never nearly enough to feed a founder population. Archaeologists argue: “When wastes
accumulated, nomadic people would simply move to another location.” (Pichtel, 2005). To es-
tablish the new wolf-population shaping dogs, the Coppingers calculated, a dump size should
provide food for 20 specimens, because 20 specimens were needed for a reproductive population
to found a new wolf-type from which dogs could have been derived (Coppinger & Coppinger,
2016). e Coppingers further calculated that one dog needs the waste and feces of 14 people to
survive (Coppinger & Coppinger, 2016). erefore, we would need the waste and feces of at least
280 people for only one wolf-dog founder population. at is at least six-times too much for the
real Homo sapiens living in that period – even if he would have produced food waste dumps.
Paleolithic (temporarily) settlements simply could not have been big enough to provide a wolf-
dog-founder population even if they would have produced feces and food remains.
4. Adaptation to starch-rich diet started long after
e scavenging hypothesis proclaims: “e dog is a shape that evolved to a new niche that
was created when people switched from hunting and gathering to growing grain. e waste
products of that activity created a food supply that supports village dogs”. (Coppinger, 2016)
Some authors are going on to say, that: “Only a time-machine would allow us to determine
which scenario occurred, and quite possibly both processes played a role. However, indepen-
dently of which pathway dogs took during domestication, the feeding niche of today’s wolves
and dogs is remarkably dierent from each other and likely has been since the advent of cultiva-
tion” (Marshall-Pescini et al., 2015). Today’s dogs are living together with humans and they are
used to human food as nutrition for thousands of years before the advent of settled agriculture.
During the time range humans were living as hunters together with their dogs – a time range
quite longer than the time range of settled agriculture – meat has been used as dog’s main or
only diet, sometimes maybe a special meat diet. From the Gravettian site of Predmostí I, 25-
27,000 years old, we have evidence, that protodogs had a high proportion of reindeer and mus-
kox in their specic diet (Bocherens et al., 2014). At the beginning of settled agriculture, dogs
had been slowly and only partly adapted to starch-rich diet (Axelsson et al., 2013), starting 7,000
years before present (Ollivier et al., 2016). Diet adaptation in dog even reects the spread of pre-
historic agriculture. us Nordic dog breeds are showing very little adaptation to starch-rich
food till today (Arendt et al., 2016) and some breeds e.g. Laiki are still hunting small game for
their own food (Beregovoy, 2001). On the other side some recent wolf populations are adapted to
marine dietary niches (Darimont et al., 2014). erefore, today’s food habits cannot create any
explanation for domestication much more than 10,000 years ago. Domestication of plants as the
basic feature of agriculture (settled or not) started less than 12.000 years bp (Meyer & Purugga-
nan, 2013). Dogs derived many thousands of years before that period and especially before grain
became a regular ingredient of dog’s diet.
5. Why wolves and not foxes?
e scavenging hypothesis argues, that it was only the wolf which occupied the new ecologi-
cal niche provided by human food waste. Scavenging and hanging around human settlements
wolves with a temperament allowing them to approach these dumps showed higher reproduc-
44
tive success which favored their self-domestication. From generation to generation, they were
genetically selected to be more tolerant to humans. us, dogs derived. Actually, it is commonly
accepted that an ancient subspecies of the wolf was the only ancestor of recent dogs (Skoglund,
2015; Fan et al., 2016; Freedman et al., 2014; almann et al., 2013). However, why wolves and
not hyenas, bears, badgers, jackals, coyotes or foxes have been domesticated? ey all were liv-
ing in that period in the proximity to Homo sapiens. Many predators scavenging at least oc-
casionally were living in the Paleolithic cold steppe, even Homo sapiens himself. Foxes (Vulpes
vulpes) like scavenging on waste dumps (Hewson, 1983; Young, 2015). Foxes can be tamed very
well as demonstrated in the Farm-fox experiment (Trut, 1999). ey are smaller than wolves
and, living near or inside the camps, they would have been no potential risk for death of clan
members, especially toddlers (Kubinyi et al., 2007). Foxes like scavenging even downtown in big
cities like Berlin (Hewson, 1983; Young, 2015). If scavenging and hanging around human settle-
ments would have been the crucial impact of domestication, foxes or jackals would have been
much better candidates for a self-domestication process on the waste dump. But it is likely, that
neither foxes nor jackals were ever been domesticated in any culture or at any time. e scav-
enging hypothesis cannot explain why only the wolf, a potential dangerous and direct competi-
tor, living in the same ecological niche, hunting the same game, should have been domesticated.
6. Evidence for pre-historic working dogs
We have evidence for dogs specialized in polar bear hunting and also special sled dog
“breeds” (something like breeds) working together with hunter-gatherers 8,000 years ago (Pit-
ulko & Kasparov, 2017). On Zhokhov Island in the far north of Siberia humans always lived in
hunter groups. ey never built any permanent settlements. Since the beginning of the Neolith-
ic period, we have growing evidence for dogs as specialized working partners for hunting, herd-
ing, sledding, guarding in many regions (Guagnin et al., 2018; Pitulko & Kasparov, 2017; Perri,
2016; Jung, 2011). We know cave paintings and rock art from northern-Africa or the Arabian
Peninsula showing man and dog hunting or herding together thousands of years before advent
of settled agriculture in these regions (Guagnin et al., 2018; Coulson & Campbell, 2001; Holl,
2004). A dog, able to work together with humans, an already specialized dog, maybe something
like an early dog breed, could not derive just from scavenging and hanging around on waste
dumps. “Breed” dogs when fossilized are only the late, visual result, not the (practical) begin-
ning of an active partnership. e early onset of specialized working “breeds” (fossilized) means
a much older working-together-culture.
7. Honor for a scavenger?
Archaeologists have found a lot of Paleolithic graves containing dogs or dogs and humans
together all over the world e.g. in the Green County, Illinois, USA, 8,500 years old, a human-
dog grave in Israel 12,000 years old and in Oberkassel, Germany, 14,200 years old (Morey &
Wiant, 1992; Morey, 1994; Janssens et al., 2018). It surely was a hard work to scoop out a grave
with stone tools. e corpses had been buried carefully, partly provided with food for a life aer
death. From a psychological point of view, we can assess such burials as an honor. It seems very
unlikely, that so much respect had been shown just for a scavenger hanging around. We fur-
ther might argue that such dogs were ceremonially buried to serve as guards or to help a dead
hunter in the aerlife. And this would have been an honor for the dogs as well. Both options
do not t to an animal characterized as a scavenger, hanging around, eating carrion and feces.
Careful analysis of the remains of the oldest human-dog grave in Oberkassel gives us an impres-
sion about dogs emotional relationship to Paleolithic people (Janssens et al., 2018). e grave in
Oberkassel contained two humans and in addition the remains of two dogs, an older one and a
45
puppy. e pup died at an age of seven months. An analysis of its bones and teeth revealed that
it likely had a serious case of morbillivirus and it likely contracted the disease at around three
to four months of age. It probably suered from two or three periods of serious illness. Without
special care, this young dog would have died very shortly aer contracting it the rst time. But
it received intensive human care. “Without adequate care, a dog with a serious case of distemper
will die in less than three weeks”, lead-researcher Janssens explains (Janssens, 2018). is dog
was clearly seriously ill but it survived a further eight weeks, which would only be possible if it
had been well cared for. Janssens goes on to say: “at would mean keeping it warm and clean
and giving it food and water, even though, while it was sick, the dog would not have been of any
practical use as a working animal. is, together with the fact that the dogs were buried with
people who we may assume were their owners, suggests that there was a unique relationship of
care between humans and dogs as long as 14,000 years ago.” (Janssens, 2018) Working and liv-
ing together, not side by side, leads to interspecic emotional bonds, to reputation and honor.
Would have people shown so much care just for a scavenger?
8. Cooperation or competition
Recent European and North American cultures produce an image of the human-wolf rela-
tionship as a hostile rivalry and the wolf is seen only as a competitor (Fogg & Pierotti, 2017). In
all regions of Europe wolves have been strongly hunted for hundreds of years. Wolves have been
exterminated in wide areas, from Europe over Asia up to North America since a long time. To
survive gray wolves have to become very timid. eir recent behavior is the result of a strong se-
lection favoring the shyest and least human socialize able specimen (Boitani, 1995). us, recent
wolves have strongly internalized to avoid any human contact. But not all wild wolves do so. e
Artic wolves on Ellesmere or Ban Islands in the far north of America do not fear humans as
much. Artic wolves (Canis lupus arctos) have never been hunted in large scale. ey are inter-
ested to contact humans (Mech, 1997; Marshall omas, 2000; DeLallo, 2011). It is documented,
that human lived with Arctic wolf packs over several month, even allowed to look aer the pups
in the den when the pack was hunting (Fogg & Pierotti, 2017). ose Artic wolves accepted hu-
man individuals as a kind of pack members.
9. Wolf as a friend in Native cultures
Indigenous peoples use to describe wolves are brother, grandfather, relative, companion,
teacher and even creator (Schlesier, 1987; Marshall 1995; Fogg et al., 2015). From hunters of
Siberia to Native Americans wolves and dogs are seen with much respect, mostly as friends or
companions. In the pre-Christian religions and mythologies wolf is described in a similar way
and regularly as a divinity or a companion of a divinity (Oeser, 2007). It is quite rarely that the
wolf is mainly described as an aggressive animal or only as a competitor. But the Wolf is never
described as scavenger nor hanging around human settlements (Fogg & Pierotti, 2017).
Discussion
In these nine issues, we did not nd any evidence for the basic assumptions of the scavenging
hypotheses neither from an archaeological, nor from an evolutionary, paleozoological, biologi-
cal or cultural point of view. e fundamental assumption of the scavenging hypotheses in all
variations is, that the ecology of wolves, characterized by “Group-hunting of ungulates” should
have been changed to a new ecology of dogs characterized by “Human refuse scavenging” (Mar-
shall-Pescini et al., 2015). ese models proclaim that the domestication process of dogs would
46
have been based fundamentally on a scavenging niche provided by humans and scavenging
would be the real nature of dogs until today. Coppingers assume: “e message of this chapter
is, those look-a-like dogs, in the same way as look-a-like pigeons, have evolved right there in
their niche and are uniquely adapted to this niche. ey are not escapees from irresponsible dog
(or pigeon) owners. ey are a natural species that lives close to humans, nds its own food, and
mates perfectly well without human control” (Coppinger & Coppinger, 2016). We have demon-
strated that it is quite unlikely, that a sucient scavenging niche existed during the time range
dog originated. It is unlikely as well, that the scavenging hypothesis should be the main evolu-
tionary story for a non-human animal, called human’s “best friend”, closely living and coopera-
tively working with humans.
Interspecic emotional bonding
Unfortunately, we do not have a time machine, but scientists from many disciplines are col-
lecting hints and even evidence to ll out the dog domestication mosaic. Step by step, we are
getting a more accurate approach to the time range when the domestication of the wolf began
(eofanopoulou et al., 2017). e grave in Oberkassel e.g. gives as a serious hint about dog’s
emotional relationship to the Paleolithic people, like basically all burials of dogs in that period.
In addition, we have many psychological and neurobiological arguments not only to explain re-
liably such emotional bonds in the Paleolithic period. Emotional bonds and common graves are
indicating that both species had shared their lifetime. Humans and dogs had lived together, not
side by side like animals hanging around as scavengers on hypothetic waste dumps. Human as-
sociated wolves and hunter-gatherers became familiar, behavioral cultures were formed (Wayne,
2014; Foote et al., 2016; Filatova et al., 2015; Avital & Jablonka, 2000). It is likely that humans
and dogs were working together and that dogs had been selected therefore which had been
started in the Upper Paleolithic period (Wang, 2013; Jung, 2011). Man and dog hunted together
in the Eurasian cold steppe (Shipman 2015; Coulson & Campbell, 2001; Holl, 2004) as well as
in many other regions e.g. Persia (Hole, 2007), Japan (Perri, 2016) or the Arabian Peninsula
(Guagnin et al., 2018). Lead researcher Guagnin (2017) goes on to resume: “Hunting scenes de-
picted in the rock art illustrate dog-assisted hunting strategies from the 7th and possibly the 8th
millennium BC, predating the spread of pastoralism.” Working together with dogs must have
been an essential condition for humans to keep wild goats starting the era of livestock farming.
Man and dog protected each other to avert danger. Dogs are used for transportation for at least
9.000 years (Pitulko & Kasparov, 2017). Pitulko & Kasparov assume: “It can be hypothesized
that dog teams might have been used in Siberia as early as 15,000 years ago.” It is a long way to
develop the ability to herd, hunt and transport together as an interspecic team. Even the tam-
est wolf would never be interested in herding, sledding, or hunting together. Dogs are actively
interested in working together with their people. is trait is commonly called “will-to-please”.
If we have specialized dogs as herding, hunting, sledding partners since thousands of years.
Hence, dogs must have been evolved completely and segregated from their wild ancestors. is
segregation should have been primarily based on mental skills (Saetre et al., 2014; Pörtl & Jung,
2015, 2017; Fogg & Pierotti, 2017). Canis lupus really provided all basic requirements to evolve
such abilities of cooperation with humans as later seen in dogs.
Why foxes cannot become dogs
Foxes do not provide these basic requirements, although they are also canid hunters and
scavengers. ey like human waste dumps. Foxes use to steal chicken in the middle of human
settlements and do not have any fear of living close to humans even downtown in the biggest
cities with much trac (Plumer, 2014). erefore, they should have been the ttest candidates
47
for a domestication process as scavenger on human waste dumps. Nevertheless, foxes have never
been domesticated naturally. Foxes are loner, whereas wolves are highly social. at is one of
the crucial dierences. Jackals (Canis aureus) are socially living in family groups. ey are scav-
engers and hunters. However, they are hunting only small game, mainly rodents, and mostly
alone (Lanszki & Heltai, 2002). Hunter and gatherer in the Paleolithic period preferred big game
like mammoth or bison. ey were hunting collectively. Human and wolf hunted the same big
mammals with the same cooperative methods in exactly the same ecological niche. Arriving in
the Paleolithic cold steppe at least 40,000 years ago, our human ancestors did not have any prac-
tice how to hunt a mammoth (Shipman, 2015; Fogg & Pierotti, 2017). Wolves already lived there
for many thousands of years well used to hunt big dangerous prey very successfully. It is not
unlikely that the rst Homo sapiens observed wolf packs hunting big prey and so learned bet-
ter how to do it by himself. Native American people claim to have learned to hunt from wolves
(Schlesier, 1987; Marshall, 1995; Fogg et al., 2015). Native people in Northern America used to
hunt bison with a wolf mask (Marshall, 1995; Fogg & Pierotti, 2017).
The crucial role of the HPAaxis...
e Siberian Farm-fox-experiment demonstrates that modulations of the Hypothalamic-pi-
tuitary-adrenal (HPA) stress axis are playing a key role in domestication (Hekman et al., 2018).
Domestication includes decreased aggression and decreased ight distance concerning to hu-
mans (Benecke, 1994; Hare et al., 2012). us, a decrease of HPAaxis activity is fundamental in
dog’s domestication process (Pörtl & Jung, 2017). Regulation of HPAaxis is inherited epigeneti-
cally and thus operates very quickly during evolution (Pörtl & Jung, 2017; Ahmed et al., 2014;
Trut et al., 2009; Buschdorf & Meaney, 2015). Due to increased interspecic pro-social contacts
between wolves and humans epigenetically based down regulation of HPAaxis promoted better
executive functions and improved social learning capability in both species (Miklosi et al., 2003;
Hare et al., 2005). us, tamed wolves became domestic dogs by integrating themselves into hu-
man social structures. And humans increased their social and cultural practice also described
as human self-domestication syndrome (Hare, 2012).
… and social similarities.
It is commonly accepted, that humans and wolves period lived in similar structured highly
social family groups during the Paleolithic (Mech, 1999¸ Page et al., 2017). ey reared their
ospring collectively (Page et al., 2017). Both hunted in-group cooperatively in exactly the
same ecological niche (Shipman, 2015). ey must have seen, smelled, heard and felt each other
very intensively. us, individual bonding was enabled (Bartal et al., 2011; Romero et al., 2014;
Joly-Mascheroni et al., 2008). Sharing the same ecological niche and the same behavior leads to
similar experience. Hence creating an enlarged interspecic resonance space facilitating empa-
thy. We have to deal with those social traits to identify the neurobiological reasons for the wolf’s
self-domestication and the deriving cooperation abilities.
Behavioral cultures for cooperation
In the today’s western culture, the wolf is seen only as a competitor (Fogg & Pierotti, 2017).
Recent Arctic wolves, mythologies all over the world and the cultural heritage of native Nordic
peoples report an alternate role (Fogg & Pierotti, 2017). e wolf is described as a cooperation
partner, as a teacher, a friend like described above. Wolves and dogs have never been addressed
as scavengers hanging around humans – neither in mythologies nor from Native Peoples. Re-
cent Artic wolves are actively interested in contact with humans, even joining to them. ere-
48
fore, it seems not to be unlikely that some Paleolithic hunter clans and some wolf packs once
established a loose tradition of cooperation. Both species are able to form behavioral cultures for
interspecic cooperation and to pass them on from generation to generation (Heinrich, 1999;
Wayne, 2013). Later on as result: Better hunting success and more power to defend the carcass
against third predators could have been some of the direct advantages of this cooperation. Nev-
ertheless, the main impact might have been on the mental site.
Neurobiological requirements for cooperation
Scientic research of dierent disciplines like neurosciences and psychology validates in-
creased evidence for similar social functions of dogs and humans (Spunt et al., 2017; MacLean
et al., 2017b). Research of brain activities demonstrate very similar mental functions (Ledoux,
2012; Gimpl & Fahrenholz, 2001; Reep et al., 2007) which enabled both of them to interact and
communicate with each other (Heberlein et al., 2016; Darwin, 1910). fMRI pictures and movies
demonstrate nearly same activities of brain regions in dogs and humans (Desmet et al., 2017;
Andics et al., 2014; Berns et al., 2012; Berns, 2015, 2017) like EEG transients as well (Iotchev et
al., 2017). We can measure basically the same release of neurohormones in both species (Ma-
cLean et al., 2017a; Berns, 2015, 2017). We have reliable evidence concerning interspecic func-
tions like mirror neurons, joint attention and even empathy (Romero et al., 2013; Szánthó et
al., 2017). Dogs are able to discriminate and recognize the emotion of a human face simply by
using parts of human faces (Huber et al., 2013; Albuquerque et al., 2016). Dogs show emotional
contagion with other dogs, but also with humans (D’Aniello et al., 2018; Takaoka et al., 2015;
Custance & Meyer, 2012; Yong & Ruman, 2014; Huber et al., 2006). Dogs understand a lot of
communicative signals like odor, expressions, gazing or pointing and even some of our inten-
tions (Kaminsky et al., 2013; Kujala et al., 2017; Schwab & Huber, 2017). Eventually we have pre-
liminary evidence for interspecic eory of Mind in dogs in relation to humans (Müller et al.,
2015). Last but not least we have to deal with very interesting facts due to modulations of neu-
rotransmitters and stress axis functions, where we see signicant similarities in functions and
epigenetic modulations (Meaney & Szyf, 2005; Kis et al., 2017; Cimarelli et al., 2017; Hekman
et al., 2018). In sum we have reliable evidence for similar social skills of human and dog due to
similar brain functions. ese similarities are much stronger than similarities with our closed
genetic relatives under the non-human animal kingdom.
Today’s evidence for similar social skills are at least reliable hints at social skills of Paleolithic
humans and their evolving dogs (eofanopoulou et al., 2017). To sum up, with archaeological,
paleogenetical and paleozoological ndings we got a powerful framework to understand the
mental and social conditions of dog domestication. erefore, we get a growing foundation to
understand the inner processes that turn a wolf into a dog. 40.000 years ago, the invasive Homo
sapiens, capturing the Eurasian cold steppe, really created a new ecological niche: himself. e
nature of this new niche was not mainly or even only waste. Our hypothesis states, that it must
have been essentially a broad social process. e engine promoting this special domestication
process must have been much more than only a simple genetically selection for tameness. It
must have been an active socially based process on both sides driven by epigenetic features.
Conclusions
e scavenging hypothesis describes the rst human waste dumps as the new ecological
niche for dog’s domestication initiating genetic selection for tameness. Genetic selection for the
ability “to eat in the presence of people” (Coppinger & Coppinger, 2016) should have been the
only or at least the main factor in this self-domestication process. Eventually dogs should to be
49
characterized as scavengers, wolves as hunters (Coppinger, 2001, 2016; Marshall-Pescini et al.,
2015). In our review we have summarized that these models are unlikely and should have been
dropped.
e variety of disciplines, we have studied, do not provide any reliable evidence for human
waste dumps as a hypothetic ecological niche for dog’s domestication. Nevertheless, it is likely
that scavenging carcasses would have been one of the sites humans and wolves met each other.
And there should have been much more options to meet and to get known, eventually becom-
ing familiar with each other e.g. while hunting or camping, while defending killed prey against
thirds or rearing a lonely wolf pup. We think it is much more helpful to look at the psychologi-
cal factors allowing a wild wolf to live voluntary within human societies without stress on both
sides, without leashes and eventually working cooperatively with humans. We suggest genetic
selection as a necessary prediction but not a sucient explanation of dog’s domestication path-
way (Jensen, 2015).
We are proposing the hypothesis of the “Active Social Domestication” of dog (Pörtl & Jung,
2013, 2015, 2017). As the name already implies, this model describes dog’s self-domestication as
an active socially based process concerning both species. is unique kind of domestication was
primarily an interspecic social process. Prosocial interactions reduce the activity of the stress
axis via epigenetic modulations (Oliva et al., 2016; Meany, 2001; Weaver et al., 2004). e wolf
integrated himself into the way of life of Paleolithic hunters. It was an active process on both
sides. Evolutionary continuity of mammalian brains enabled both, human and wolf, mutual in-
teractions which reduced stress on both sides and eventually favored what we call domestication
(Ledoux, 2012; Gimpl & Fahrenholz, 2001; Reep et al., 2007; Spunt et al., 2017). Both of them
wanted to cooperate, to live together and to work with each other (Pörtl & Jung, 2015, 2017).
Advantages are known on both sides but not primarily in immediate eects like better hunting
success, protecting, watching or warming. Lower permanent stress levels promote the frontal
brain functions, contributing to better executive functions and improving social learning ca-
pabilities in both species (Hare et al., 2012). is allowed human associated wolves to grow into
domestic dogs. We suggest, that modulations of the HPA axis are playing a key role (Hekman et
al., 2018).
During the last 150 years most dogs turned from a role in human production to one in our
mental welfare (Jung, 2011; Jung & Pörtl, 2015). But this role is neither new nor less important.
Dogs have been – and still are – our social bonding partners for thousands of years. Even today
we have some preliminary evidence, that dogs provide a general healthy inuence (Mubanga et
al., 2017) and specially a healthy inuence on human stress system (O›Haire & Rodriguez, 2018;
Julius et al. 2014; Beetz et al., 2012). Dogs improve our social and cognitive abilities. In addition,
dogs feel like us as shown by neurobiological investigations (Berns, 2017).
For a better understanding of the metamorphism from the wild wolf to our family dogs, it
is indispensable to take a multi-disciplinary approach. Co-Evolution of men and wolf resp. dog
is a unique phenomenon in nature. It is an important part of our culture, social history and
economic development. To understand dogs we have to understand humans. Dog’s evolution is
very closely linked to human evolution and history. It is an archaeological and paleogenetical
issue and particularly a unique psychological and neurobiological challenge still today. Further
research should deal with psychology, neurosciences, epigenetics and further disciplines in a
broad and close multidisciplinary way.
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We declare: ere are no Sponsors and no Conicts of interest.
Daniela Pörtl and Christoph Jung contributed equally to this work.
Correspondence and requests for materials should be addressed to Christoph Jung. Obschuetzerstrasse
17. D-06667 Weissenfels. Germany Email jung@petwatch.de Phone +49 17656859000 Fax +49 321
21206281.
L’ipotesi della domesticazione attraverso il commensalismo (ipotesi “scavenging”):
non esistono evidenze scientiche di una domesticazione del cane nelle discariche
Christoph Jung1, Daniela Pörtl2
1 Petwatch,
2 Psychiatric department, Saale-Unstrut Klinikum, teaching hospital Leipzig and Jena Universities,
Naumburg, Germany
Sintesi
Nel dibattito sulla domesticazione dei cani i ricercatori hanno identicato molte informazioni riguardanti il tempo,
la regione e l’antenato del cane. Ma i ricercatori stanno ancora cercando di capire perché e come sia iniziato questo
processo. La “scavenging” ipotesi, proposta per la prima volta nel 2001 da Ray e Lorna Coppinger, sostiene che le prime
discariche di riuti umani siano state la nicchia ecologica per il processo di auto-domesticazione dei cani. Molti ricerca-
tori si riferiscono a quel modello, a volte parzialmente modicato. L’ipotesi di scavenging è diusa dalla maggior parte
dei media pubblici come il modello comunemente accettato di domesticazione del cane. Quindi dobbiamo occuparci
di quel modello popolare. Basandoci su un ampio approccio multidisciplinare come evoluzione umana, archeologia,
paleogenetica, psicologia e neurobiologia, cercheremo di trovare le prove esitenti.
Indagando su nove ipotesi dell’ipotesi di “scavenging”, non abbiamo trovato alcuna prova. La domesticazione del
cane iniziò migliaia di anni prima dell’avvento delle discariche di riuti alimentari. L’ipotesi di “scavenging” non può
spiegare perché solo i lupi e non le volpi e gli sciacalli siano stati addomesticati.
I popoli paleolitici e i lupi vivevano insieme nella stessa nicchia ecologica, cacciando le stesse prede con gli stessi
metodi cooperativi. È probabile che si siano incontrati molto spesso e si conoscessero molto bene. Esistono alcuni indizi
che i lupi e le persone si siano trattati con rispetto in modo cooperativo e che vi sia stata una cooperazione attiva tra uo-
mini e cani a partire dal Paleolitico superiore, molto prima che fosse possibile nutrirsi di riuti umani. Esistono prove di
legami emotivi tra l’uomo preistorico e cani. I legami emotivi sarebbero stati improbabili per un animale che gironzolava
attorno agli insediamenti umani mentre scavava carogne e feci, come descrivono le ipotesi di “scavenging”. Guardando
i cani e gli esseri umani attuali abbiamo prove di forti somiglianze uniche nelle strutture psicologiche e neurobiologiche
che consentono un legame interspecico, la comunicazione e il lavoro.
56
La cooperazione interspecica ha ridotto l’attività dell’asse ipotalamo-iposi e surrene di entrambe le specie nel pe-
riodo Paleolitico e lo fa anche oggi e ciò migliora le nostre capacità sociali e cognitive. In questa review si propone che
l’addomesticamento dei cani possa essere inteso come un processo sociale attivo di entrambe le parti. Ulteriori indagini
richiedono un approccio multidisciplinare strettamente connesso.
... Some authors have argued that the first dogs provided no services at all, but were simply scavengers around human camps (Coppinger and Coppinger, 2001). But there is a lack of evidence for dog domestication on the waste dump (Jung and Pörtl, 2018). Even the timeline does not fit. ...
... Cave paintings and rock art from Northern Africa or the Arabian Peninsula from 9 to 10 kya show men and dogs hunting or herding together (Coulson and Campbell, 2001;Holl, 2004;Guagnin et al., 2018). As cultures and technologies developed, jobs carried out by working dogs did so as well, resulting in the separation of dogs into different types of animals selected for different working functions, and ultimately, in dozens of breeds (Jung and Pörtl, 2018). Parker et al. (2017) have proposed a two-step process of breed creation: first, separation by functional employment; later, selection for physical attributes. ...
... Dog or human-dog graves have been found much more frequently than that of cats, horses, or other animals. This circumstance tells of a deep emotional link between dogs and Paleolithic people (Janssens et al., 2018;Jung and Pörtl, 2018), particularly if one considers that in the Oberkassel grave one of the buried dogs had been ill for several months and had received intensive human care before dying (Janssens et al., 2018). As noted, these intense inter-specific contacts are expected to have contributed to reducing reactive aggression in both humans and dogs and to increasing tolerance toward non-kin. ...
Article
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Different factors seemingly account for the emergence of present-day languages in our species. Human self-domestication has been recently invoked as one important force favoring language complexity mostly via a cultural mechanism. Because our self-domestication ultimately resulted from selection for less aggressive behavior and increased prosocial behavior, any evolutionary or cultural change impacting on aggression levels is expected to have fostered this process. Here, we hypothesize about a parallel domestication of humans and dogs, and more specifically, about a positive effect of our interaction with dogs on human self-domestication, and ultimately, on aspects of language evolution, through the mechanisms involved in the control of aggression. We review evidence of diverse sort (ethological mostly, but also archeological, genetic, and physiological) supporting such an effect and propose some ways of testing our hypothesis.
... Based on genetic evidence from both modern humans and dogs (Druzhkova et al., 2013;Germonpre et al., 2009;Ovodov et al., 2011), it is hypothesized that early humans' migration out of Africa into Paleolithic cold steppe (i.e., today's Eurasia), and their first encounters with wolves are suggested to have happened at approximately the same time, namely, 40,000 years B.P. (Pierotti & Fogg, 2017). Paleolithic hunter-gatherers and wolves showed remarkable similarities in their lifestyles: (a) both species lived in social groups, (b) they preferred to hunt big game -e.g., mammoth or bison, and (c) they were hunting cooperatively (Jung & Pörtl, 2018). Archaeological evidence (e.g., bones of wolves have been found in association with those of early hominins) further indicates that the sites of occupation and hunting activities of both species may have overlapped often (Clutton-Brock, 2017). ...
... Archaeological evidence (e.g., bones of wolves have been found in association with those of early hominins) further indicates that the sites of occupation and hunting activities of both species may have overlapped often (Clutton-Brock, 2017). It is thought that early Homo sapiens observed wolf packs hunting big prey, and so learned how to do it better themselves (Jung & Pörtl, 2018). During their encounters, humans may have repeatedly adopted wolf puppies and allowed the most cooperative individuals to reproduce (Kukekova et al., 2014). ...
... Over the last two decades, different fields of research have investigated why dogs have been, and continue to be, successful in cohabitating with humans (Jung & Pörtl, 2018). First, we consider how two interdisciplinary fields of research, namely anthrozoology (i.e., the study of human and nonhuman animal interactions) and comparative cognition (i.e., the study of cognitive, emotional and social skills of animals), assess and characterize human-dog interactions. ...
Article
Mounting interest in the evolutionary and contemporary aspects of human-dog association has resulted in growing research efforts from different disciplines with differing methodologies and areas of emphasis. Despite its potential to contribute to the understanding of human-dog interactions, behavior-analytic research efforts are scarce. We are illustrating how the behavior-analytic three-level selection by consequences framework could be applied to inform research on human-dog interactions. Therefore, the notions of interlocking behavioral contingencies and metacontingencies are applied to interpret specific interactions and suggest potential lines of research. We first analyze the development of cooperative hunting of prehistoric humans and dogs, and its implications for interspecific social-communicative skills. Second, we discuss contemporary family practices that involve the interactions between parents, children and family dogs via an analysis of a prototypic social episode. Lastly, we provide an overview of the main approaches that have contributed to the understanding of the human-dog interactions (e.g., anthrozoological), and show how their findings can be placed within the behavior-analytic framework. We conclude that the coherence of the selectionist framework is a major strength that not only can contribute to synthesize a large amount of scattered research on human-dog relationships conducted across various fields, but can also inform further research and applications.
... Notably, the older end of this range is roughly coincident with the migration of Homo sapiens into Europe (Conard and Bolus, 2008). Animal domestication involves shaping and controlling the evolutionary pathway of another species; thereby reflecting a shift in the human psyche on its relationship with nature (Boudadi-Maligne et al., 2012;Jung and P€ ortl, 2018). The timing of this first domestication process is important knowledge for understanding early Homo sapiens cognition, behavior, and ecology during the Last Glacial Period as well as for discerning the initial impetus for human-wolf interactions. ...
... Human refuse exploitation is a learned behavior seen in free ranging dogs (Vanak and Gompper, 2009;Forsyth et al., 2014), and other canids, including coyotes, foxes and wolves today (Murray et al., 2015;Bateman and Fleming, 2012;Forsyth et al., 2014). It is unclear whether Paleolithic campsites contained enough surplus or refuse to entice invasive wolves (Lupo, 2017;Germonpr� e et al., 2018;Jung and P€ ortl, 2018), but scavenging efficiency of protodogs may have been encouraged as a means of site management by removing refuse from occupation sites (Coppinger and Coppinger, 2001;Russell and Twiss, 2017). ...
Article
Morphological and genetic evidence put dog domestication during the Paleolithic, sometime between 40,000 and 15,000 years ago, with identification of the earliest dogs debated. We predict that these earliest dogs (referred to herein as protodogs), while potentially difficult to distinguish morphologically from wolves, experienced behavioral shifts, including changes in diet. Specifically, protodogs may have consumed more bone and other less desirable scraps within human settlement areas. Here we apply Dental Microwear Texture Analysis (DMTA) to canids from the Gravettian site of P�redmostí (approx. 28,500 BP), which were previously assigned to the Paleolithic dog or Pleistocene wolf morphotypes. We test whether these groups separate out significantly by diet- related variation in microwear patterning. Results are consistent with differences in dietary breadth, with the Paleolithic dog morphotype showing evidence of greater durophagy than those assigned to the wolf morphotype. This supports the presence of two morphologically and behaviorally distinct canid types at this middle Upper Paleolithic site. Our primary goal here was to test whether these two morphotypes expressed notable differences in dietary behavior. However, in the context of a major Gravettian settlement, this may also support evidence of early stage dog domestication. Dental microwear is a behavioral signal that may appear generations before morphological changes are established in a population. It shows promise for distinguishing protodogs from wolves in the Pleistocene and domesticated dogs from wolves elsewhere in the archaeological record.
... Though superficially plausible, this account of wolf domestication is not without its challengers. The eminent geographer, Sauer (16), for example, referred to this theory as "an attractive myth, " and more recently, Jung and Pörtl (17) have strongly disputed the notion that late Pleistocene humans in Europe or Asia reliably generated enough carrion or waste to sustain a permanent population of scavenging wolves. Current evidence suggests that the wolf was already domesticated by the end of the Last Glacial Maximum (LGM) about 15 K years ago (kya) when humans still lived in the relatively small and highly dispersed nomadic groups associated with typical hunting and foraging societies (18). ...
Article
Full-text available
The work of archaeozoologists and molecular geneticists suggests that the domestication of the wolf (Canis lupus)-the ancestor of the domestic dog (C. familiaris)-probably occurred somewhere between 40,000 and 15,000 years ago somewhere on the Eurasian continent, perhaps in more than one location. Wolf domestication was therefore underway many millennia before the origins of agriculture and the domestication of food animals, such as sheep and goats. Currently, there are two predominant "origin stories" concerning the domestication of the wolf. The dominant narrative in recent literature is the commensal scavenger hypothesis which posits that wolves essentially domesticated themselves by invading ancient human settlements in search of animal remains and other edible waste discarded by hunter-gatherers. Over time, tolerance by humans gave a selective advantage to the bolder, less fearful wolves, which then diverged from the ancestral population as they adapted to the new scavenging niche. At some point in the process, humans also began to recognize the benefits of living with resident, semi-domestic wolves, either as guards or as hunting partners, thereby cementing the relationship. The alternative account of wolf domestication is very different. Sometimes known as the pet keeping or cross-species adoption hypothesis, this narrative draws heavily on anthropological observations of pet keeping among recent hunter-gatherers, and postulates that Paleolithic peoples were similarly inclined to capture, adopt and rear infant mammals, such as wolf pups, and that this habitual human nurturing behavior ultimately provided the basis for the evolution of a cooperative social system involving both species. This review critically examines and analyzes these two distinct domestication narratives and explores the underlying and sometimes erroneous assumptions they make about wolves, Pleistocene humans, and the original relationships that existed between the two species. The paper concludes that the commensal scavenger hypothesis is untenable based on what is known about recent and ancient hunter-gatherer societies, and that wolf domestication was predicated on the establishment of cooperative social relations between humans and wolves based on the early socialization of wolf pups.
... "Protodogs" as a signal of earlier domestication, have been contested by many, mainly based on lack of genetical closeness to dogs (Thalmann et al., 2013), lack of important size reduction, doubts about real differences in diet and dental wear, doubts about the validity of discerning metrics and on methodology ( Ameen et al., 2017;Boudadi-Maligne and Escarguel, 2014;Crockford and Kuzmin, 2012;Drake et al., 2015;Janssens et al., 2019a;Jung and Pörtl, 2018;Ledoux and Boudadi-Maligne, 2015;Morey, 2010;Morey and Jeger, 2015;Napierala and Uerpmann, 2012;Perri, 2016;Pitulko and Kasparov, 2017;Wilczynski et al., 2020). ...
Article
In a recent article in this journal, Galeta et al., (2020) discussed eight Pleistocene "protodogs" and seven Pleistocene wolves. Those "protodogs" had been diagnosed in earlier publications, based on skull morphology. We re-examined the Galeta et al. paper to offer comments on their observed outcomes, and the conclusion of presumed domestication. Of seven metrics that the authors used, five differed statistically between their two groups. However, from more elaborate studies, some of those same metrics had been rejected previously as not valid species-distinguishing traits. In this respect, we do accept cranium size and wider palate as species-distinguishing metrics. The physical size of their specimens was much larger than other archaeological specimens that have been accepted as dogs. Additionally, their sample size was small, compared to the number of available specimens, as shown from previous publications by the same group. Thus, we considered statistical differences that were found between groups in their study, and assessed whether the outcomes could have resulted from natural morphological variation. We examined a group of 73 dire wolves ((Aenocyon [Canis] dirus; Perri et al., 2021), using the same methods as used by Galeta et al., (2020). We could segregate two distinct morphological groups in our study, one having outcomes that were identical to the "protodogs" in Galeta et al. (2020). For the specimens of extinct dire wolves to segregate in the same way as the subjects from Galeta et al. indicates that natural variation probably was the driver of their observed outcomes, domestication being an unlikely assumption.
... In addition, it is commonly agreed that dog domestication began in the Upper Paleolithic period, but human settlement started only in the Neolithic period (Shipman, 2015;Thalmann et al., 2013). Therefore, the hypothesis of dog domestication at the waste dump also appears rather unlikely, although the idea of a self-domestication is still plausible because intentional breeding of wild wolves could not have been accomplished by hunter-gatherers without chains or stables (Jung & Pörtl, 2018). Therefore, genetic selection caused by intentional breeding cannot be the initiating first step of domestication from wolf to dog, although it surely played an important role in further dog breeding. ...
Article
Full-text available
Dogs (Canis lupus familiaris) descend from wolves (Canis lupus) sharing the same ecological niche of cooperative hunters, as humans. Initially, humans and wolves were competitors starting interspecific communication in order to avoid risk of injury. The evolutionary continuity of mammalian brains enabled interspecific prosocial contacts between both of them, which reduced stress, and enabled behavioral cultures leading to genetic isolation of those wolves. Dogs are the first domesticated animal living together with humans for about 25,000 years. Domestication means decreased aggression and flight distance toward humans, thus changes in the stress axis are crucial. The hypothesis of Active Social Domestication considers genetic selection as a necessary prediction but not a sufficient explanation of dog domestication. In addition, dog domestication is suggested to be an epigenetic disclosure. Due to changed stress activity, epigenetic mechanisms affect cerebral receptor activity and regulate transposon expressions, thus shaping brain function and behavior. Interspecific prosocial contacts initiated via serotonin release an enzymatic cascade enhancing, epigenetically, the glucocorticoid negative feedback loop. Reduced chronic stress improved social learning capability and inhibitory control. Over time, those wolves could integrate themselves into human social structures, thus becoming dogs. In analogy, human mental skills, such as creating art and culture, might have also improved during the Upper Paleolithic.
... Wachen, Beschützen, Jagen, Schlitten-und später Wagen-Ziehen, Schafe-Hüten und RinderTreiben sowie unzählige weitere Aufgaben erfüllten Hunde. Wär-men in der Nacht, Spielgefährte der Kinder und die Rolle als Sozialpartner zählten bereits früh zu seinem Repertoire (Jung & Pörtl, 2018). Der Hund erfüllt diese Aufgaben aus eigenem Antrieb heraus. ...
Article
Full-text available
Only we humans select traits by breeding that cause suffering to animals. And our pets, the animals we are emotionally most attached Qualzucht – warum wir unsere Lieblinge quälen to, suffer the most. Instead of protecting them, we allow their breeding to promote those features that cause them pain and suffering. We even finance cruel breeding. Despite all the efforts of animal protection: Cruel breeds have never been as popular as they are now. This contradiction leads to the fundamental problem of our estrangement from nature and non-human animals. We are torn between true emotional attachment, especially to our dogs, on the one side, and a view of animals in general, but also of our pets, as merchandise, consumer goods, extended ego, on the other. We find one root of this double standard in livestock farming, which is built on breaching the trust of animals in us. Real partnership with our dogs frees not only our four-legged friends from the burden of cruel breeding; for us it is a step back towards a unity with nature and peace with ourselves. Keywords: breeding, cruel breeds, estrangement, double standards (in German) Qualzucht wird einzig von uns Menschen gemacht. Gerade die Tiere, die uns emotional am nächsten stehen, leiden am meisten. Statt sie zu schützen, lassen wir es geschehen. Wir finanzieren das Qualzuchtgeschehen sogar. Wider allen Geredes von Tierschutz: Nie war Qualzucht so präsent wie heute. Dieser Widerspruch führt zum grundlegenden Problem der Entfremdung von der Natur und den nicht-menschlichen Tieren. Wir stehen in dem Zwiespalt von echter emotionaler Bindung besonders an unsere Hunde einerseits und andererseits einer Sicht auf Tiere ganz allgemein und selbst auf unsere Pets als Ware, Konsumartikel, erweitertes Ego. Eine Wurzel dieser Doppelmoral sehen wir in der Viehhaltung, die den Vertrauensbruch am Tier zur Grundlage hat. Echte Partnerschaft zwischen Mensch und Hund befreit nicht nur die Vierbeiner von der Last der Qualzucht, es ist für uns Menschen selbst ein Schritt zur Einheit mit der Natur und zum Frieden mit uns selbst. http://www.tierethik.net/Aktuelle-Ausgabe.6.html
... In addition, it is commonly agreed that dog domestication began in the Upper Paleolithic period, but human settlement started only in the Neolithic period (Shipman, 2015;Thalmann et al., 2013). Therefore, the hypothesis of dog domestication at the waste dump also appears rather unlikely, although the idea of a self-domestication is still plausible because intentional breeding of wild wolves could not have been accomplished by hunter-gatherers without chains or stables (Jung & Pörtl, 2018). Therefore, genetic selection caused by intentional breeding cannot be the initiating first step of domestication from wolf to dog, although it surely played an important role in further dog breeding. ...
Article
Dogs (Canis lupus familiaris), derived from wolves (Canis lupus), are known as the first domesticated animal and dogs have been living in human environment for about 25.000 years. Today researchers tend to proclaim a self-domestication-process, but they are still figuring out, why and how this process started. During the Palaeolithic period, humans and wolves lived in similar structured family clans as cooperative hunters in the same ecological niche. Evolutionary continuity of mammalian brains enabled humans and wolves interspecific communication and social interaction which reduced stress and aggression during their frequently contacts as the first step of a natural domestication process. Domestication means decreased aggression and decreased flight distance concerning to humans. Therefore changes of the activity of the Hypothalamic-pituitary-adrenal (HPA) axis are suspected to be important during the domestication processes from wolf to dog. The hypothesis of Active Social Domestication (ASD) considers genetic selection as a necessary prediction but not a sufficient explanation of dog domestication. In addition dog domestication is suggested to be essentially an epigenetic based process that changes the interactions of the HPAaxis and the 5-Hydroxytryptamine (5-HT) system. The limbic brain regions such as hippocampus and amygdala play a key role in the mood control. They are sensitive to glucocorticoids and innerved by serotonergic projections. The HPAaxis and the 5-HT system are closely cross-regulated under physiological conditions. The activity of the HPAaxis is influenced thru an enhancement of the corpus amygdala and an inhibition thru the hippocampus. Hippocampal glucocorticoid receptor density (hGCR) is likely to affect its inhibitory effect on this system. Pro-social behaviour enhances epigenetically hGCR expression via increased serotonin and subsequently increased nerve growth factor levels binding on GRexon1;7promotorbloc inducing its demethylation and thus leading to decreased cortisol levels. Low cortisol levels increase social learning capability and promote the activity of the prefrontal cortex contributing to better executive function including better cognitive inhibition. Thus epigenetically decreased cortisol levels of less stressed human-associated wolf clans allowed them to extend their social skills to interactions with humans. Over time tame wolves could grow into domestic dogs able to emerge human directed behaviour.
Article
Based on claims that dogs are less aggressive and show more sophisticated socio-cognitive skills compared with wolves, dog domestication has been invoked to support the idea that humans underwent a similar ‘self-domestication’ process. Here, we review studies on wolf–dog differences and conclude that results do not support such claims: dogs do not show increased socio-cognitive skills and they are not less aggressive than wolves. Rather, compared with wolves, dogs seek to avoid conflicts, specifically with higher ranking conspecifics and humans, and might have an increased inclination to follow rules, making them amenable social partners. These conclusions challenge the suitability of dog domestication as a model for human social evolution and suggest that dogs need to be acknowledged as animals adapted to a specific socio-ecological niche as well as being shaped by human selection for specific traits.
Chapter
The dog (Canis familiaris L.) is the first animal species that was completely domesticated by man and has a long history as an integral part of human societies, in which it has had several roles as a companion animal, pet, work animal, or auxiliary in the search and rescue, among many others. Its population worldwide exceeds 700 million individuals, occupying practically all geographic regions and ecosystems of the planet, including many of the areas dedicated to nature conservation. Due to this, it has been considered one of the most important invasive species worldwide. This chapter includes data obtained through wildlife monitoring by means of photograph trap cameras in six artificial ponds implemented in a protected natural high mountain area of central Mexico. The data found show that Canis familiaris is the most frequently registered animal species, both in sites with artificial ponds and in places where there were no ponds. Artificial ponds favor the presence of species such as the raccoon (Procyon lotor), but also favor the presence of dogs (Canis familiaris), inhibiting the presence of native carnivores such as coyote (Canis latrans). Additionally, there seems to be a spatial and temporal displacement of wildlife activities in response to the high incidence of C. familiaris. Due to the high incidence of dogs, it is urgently recommended to establish a program of control and management of its population in this and other protected natural areas, which guarantees the objectives for which these areas were established: the protection of biodiversity and wildlife.
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Archaeological evidence from the submerged North Sea landscape has established the rich diversity of Pleistocene and Early Holocene ecosystems and their importance to hunter-gatherer subsistence strategies. Comparatively little of this evidence, however, dates to the Late Glacial, the period when Northern Europe was repopulated by colonising foragers. A human parietal bone and a decorated bovid metatarsus recently recovered from the floor of the North Sea have been dated to this crucial transitional period. They are set against the background of significant climatic and environmental changes and a major technological and sociocultural transformation. These discoveries also reaffirm the importance of continental shelves as archaeological archives.
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