Dates
for the most recent common ancestor (MRCA) for dogs and wolves are remarkable
recent. When Stan Olsen (1983) wrote his classic work on domestic dog fossils
(1983) he noted the oldest known remains were from Palegawra Cave in
northeastern Iraq with an estimated age of 12 thousand years before present (YBP).
But
subsequent evidence suggests that dogs split from wolves much latter than those
fossils would imply. Deep in Chauvet cave, in France, Garcia (2005) found a track
of footprints from a large canid associated with one of a child. Torch wipes
made by this child were dated at about 26,000 YBP. Based on the short length of
medial fingers in the footprints the canid track was interpreted as being made
by a large dog.
Genetic data also suggests that the dogs originated prior to the often cited 15,000 YBP. Ostrander and Wayne (2005) report that mitochondrial DNA (mtDNA) sequence analysis shed some light on the location of dog domestication as well as the number of founding matralines. They found dog sequences in at least four distinct clades, suggesting a single origin event and at least three other origination or interbreeding events. They also found nucleotide diversity high, implying an origin date of 135 to 40 thousand YBP. And Ostrander and Wayne (2005) suggests dogs may have had a long prehistory when they were not phenotypically distinct from wolf progenitors. Therefore early dogs may not have been recognized as domesticated in the archaeological record prior to 15,000 YBP because of their physical similarity to gray wolves.
However,
a group of morphologically distinct canids hypothesized to be early domesticated
dogs have been identified by Germonpré et al., (2009, 2012). Seven complete
large canid skulls and 26 skull fragments from the Gravettian Předmostí site in
the Czech Republic were examined, three skulls were identified as European
Palaeolithic dogs, characterized by short skulls, short snouts, wide palates
and braincases, and even-sized carnassials. The presence of dogs at Předmostí supports
the hypothesis that domestication of dogs began long before the Late Glacial.
One of the skulls was identified as a Pleistocene wolf, three other skulls could
not be assigned to a group. Furthermore, at Předmostí, several human modifications
of the skulls and canines hint at a specific relationship between humans and
large canids.
While
this has been controversial (see Crockford and Kuzmin, 2012), the evidence
continues to mount supporting a much older origin of dogs. Druzhkova et al.
(2013) provide molecular evidence that the 33,000-year old Pleistocene dog from
Altai has a unique haplotype and the Altai dog is more closely related to
modern dogs and prehistoric New World canids than it is to extant wolves.
In
a forthcoming article in Quaternary International Pat Shipman
of Pennsylvania State University asks the question, how do you kill 86
mammoths. The author examines a series of Eurasian archaeological sites formed
between about 40 and 15 thousand years ago that feature unusually large numbers
of mammoth remains with abundant artifacts and, often, mammoth bone dwellings.
Since
the late 19th century, archaeological sites dominated by mammoth remains have
been a focus for research. How the bones of large numbers of mammoths, ranging
from a minimum number of five individuals to hundreds of individuals, were
deposited in one place remains an un-answered question. And, despite previous
investigation, the cause of death of mammoths in these sites has remained
controversial.
Two
predominate hypotheses have been used to explain these megasites (a reference
to the large number of mammoth remains): (1) the mammoths died natural
deaths which were subsequently scavenged by humans; (2) or that specialized
human hunting resulted in the deaths of the mammoths. Questions about
collection and excavation techniques pose challenges for synthesizing the
information, but the wealth of material has produced numerous published zooarchaeological
analyses of the sites, including number of non-mammoth species represented,
minimum numbers of mammoths at each site, mammoth age at death, and mammoth age
profiles from individual sites.
All
of these mammoth megasites are dated after the appearance of modern humans in
Eurasia. These unusual sites are of interest given the obvious successes of the
humans that made them. But, also because of the large number of individual
mammoths and the scarcity of carnivore tooth marks and gnawing. The evidence suggest the
mammoth hunters had invented a new ability to retain and control the mammoth carcasses
– protecting all of that valuable protein from scavengers.
Age
profiles of mammoths at the megasites differ statistically at the p < 0.01
level from age profiles of African elephant populations that died of either
attritional or catastrophic causes. However, age profiles from some mammoth
sites exhibit a chain of linked resemblances with each other through time and
space, again suggesting hunter behavioral and technological innovation.
The
megasites Shipman analyzed are spread across most of the Eurasian continent and
over a substantial time span. The introduction and spread of complex projectile
weaponry by modern humans was probably important in producing the abrupt
changes in assemblages associated with hominins that started about 45,000 YBP. Previous
authors observed that reduced weight projectile weapons are a “niche-broadening
technology” because they are easily carried, retain energy longer in
flight, and they reduce the risk of injury when hunting dangerous animals or in
combat when fighting other people. Thus early modern humans may have broaden
their ecological niche. The reduced weight projectile weapons transforms the
hunters from ambush predators (as Neanderthals were) to being long-distance
hunters. Shipman also suggests a second advance which occurred during MIS 3 (marine
isotope stage 3, which started 57,000 YBP) may have enhanced the advantages of reduced
weight projectile weapon technology - a quasi-domesticated large canids willing
to work cooperatively with humans.
Shipman
(2014) hypothesize that this innovation may have been facilitated by an early
attempt to domesticate dogs, as indicated by a group of genetically and
morphologically distinct large canids which first appear in archaeological
sites at about 32,000 YBP.
Thus
at the moment it would appear that the MRCA of dogs and wolves is indeed much
older than 15,000 YBP. It also appears that dogs, were co-operating with humans
at least 32,000 YPB. But did humans domesticate the dog, or did dogs evolve
from wolves all on their own?
Citations
Crockford,
S. J., & Kuzmin, Y. V. (2012). Comments on Germonpré et al., Journal of
Archaeological Science 36, 2009 “Fossil dogs and wolves from Palaeolithic sites
in Belgium, the Ukraine and Russia: osteometry, ancient DNA and stable
isotopes”, and Germonpré, Lázkičková-Galetová, and Sablin, Journal of
Archaeological Science 39, 2012 “Palaeolithic dog skulls at the Gravettian
Předmostí site, the Czech Republic”. Journal of Archaeological Science, 39(8),
2797-2801.
Druzhkova
AS, Thalmann O, Trifonov VA, Leonard JA, Vorobieva NV, et al. (2013) Ancient
DNA Analysis Affirms the Canid from Altai as a Primitive Dog. PLoS
ONE 8(3): e57754. doi:10.1371/journal.pone.0057754.
Garcia,
M.A., 2005. Ichnologie ge’ne’ rale de la grotte Chauvet. Bulletin de la Socie’ te’ pre’
historique francaise 102, 103–108.
Germonpré,
M., Sablin, M. V., Stevens, R. E., Hedges, R. E., Hofreiter, M., Stiller, M.,
& Després, V. R. (2009). Fossil dogs and wolves from Palaeolithic sites in
Belgium, the Ukraine and Russia: osteometry, ancient DNA and stable
isotopes. Journal of Archaeological Science, 36: 473-490.
Germonpré,
M., Lázničková-Galetová, M., & Sablin, M. V. (2012). Palaeolithic dog
skulls at the Gravettian Předmostí site, the Czech Republic. Journal
of Archaeological Science, 39(1), 184-202.
Kolosov,
P. N. (2014). Primitive Mammoth Hunters and the Earliest Breed of Dog. Natural
Resources, 2014.
Olsen,
S. J. (1985). Origins of the domestic dog: the fossil record. University of
Arizona Press, Tucson. 117 pp.
Ostrander,
E. A., & Wayne, R. K. (2005). The canine genome. Genome research, 15(12),
1706-1716.
Shipman,
P. (in press, 2014). How do you kill 86 mammoths? Taphonomic investigations of
mammoth megasites. Quaternary International.
