Cave Bears and Mankind

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www.sciencedirect.com/science/article/pii/S1040618213007921

Quaternary International
Volumes 339–340, 7 August 2014, Pages 148–163

Fossil remains in karst and their role in reconstructing Quaternary paleoclimate and paleoenvironments

Behavioural ecology of Late Pleistocene bears (Ursus spelaeus, Ursus ingressus): Insight from stable isotopes (C, N, O) and tooth microwear

Several types of bears lived in Europe during the Late Pleistocene. Some of them, such as cave bears (Ursus s. spelaeus and Ursus ingressus), did not survive after about 25,000 years ago, while others are still extant, such as brown bear (Ursus arctos). Our article aims at a better understanding of the palaeoecology of these large “carnivores” and focuses on two regions, the Ach valley in the Swabian Jura (SW-Germany) with Geißenklösterle and Hohle Fels, and the Totes Gebirge (Austria) with Ramesch and Gamssulzen caves. Both regions revealed two genetically distinct cave bear lineages, and previous studies suggest behavioural differences for the respective bears in these two regions.

In the Ach valley, irrespective of the cave site, U. s. spelaeus was replaced by U. ingressus around 28 ka uncal BP with limited chronological overlap without recognizable dietary changes as documented by the isotopic composition (13C, 15N) of the bones. Furthermore, the present study shows that the dental microwear pattern was similar for all bears in both caves, however with a larger variability in Geißenklösterle than in Hohle Fels.

In contrast, the two Austrian caves, Gamssulzen (U. ingressus) and Ramesch (Ursus s. eremus), show considerable differences in both palaeodietary indicators, i.e., stable isotopes, and dental microwear, over at least 15,000 years. The oxygen and carbon analysis of the tooth enamel combined with the dental microwear of the same molars provide an extremely diversified picture of the feeding behaviour of these fossil bears. The already known differences between these two study areas are confirmed and refined using the new approaches. Moreover, the differences between the two cave bear lineages in the Totes Gebirge became even larger. Some niche partitioning between both types of cave bears was supported by the present study but it does not seem to be triggered by climate. This multi-disciplinary approach gives new insights into the palaeobiology of extinct bears.  
 

interspecific exclusion among cave residents is apparent
(Gamble 1986, Stiner 1994).
By way of anthropological background, the chronology
of Paleolithic cultures begins around the Plio-Pleistocene
boundary and lasts until the Holocene. The
Paleolithic traditionally is divided into 3 major cultural
phases: the Lower, the Middle, and the Upper Paleolithic.
The hominid forms associated with these cultures varied
considerably, and there is no simple correspondence between
cultural (behavioral) change and hominid morphological
(skeletal) change. Lower Paleolithic artifacts
are attributed to some of the late Australopithecine species,
which were confined to the African continent, as
well as to early variants of the genus Homo, which by
1.4-1.8 million years ago (MYA) spread from Africa into
much of Eurasia. First appearing some 250,000 years
ago, Middle Paleolithic artifacts are characterized by innovations
in stone tool production techniques and artifact
forms. They are attributed to archaic humans such
as Neandertals in general (H. sapiens neanderthalensis)
as well as to earliest anatomically moder humans (H.
sapiens sapiens) in the west Asian cave sites of Qafzeh
and Skhul (Bar-Yosef et al. 1986, Valladas et al. 1988,
Bar-Yosef 1989, Vandermeersch 1989). The Upper Paleolithic,
which began between 42,000 and 35,000 years
ago (depending on region), is marked by spectacular radiations
in material culture over a relatively short time
span. Artifacts of all 3 periods commonly are found in
open sites. Cave sites, usually in limestone solution cavities,
were periodically inhabited during the Middle and

Upper Paleolithic culture periods only, and most of the
archaeofaunal records of these periods come from caves
for the simple reason that cave sediments favor bone preservation.
Paleolithic peoples probably were no more
bound to caves than bears, but both were at times attracted
by the prospect of easy shelter.
Here I review available knowledge on Pleistocene human-bear
relations, as gleaned by archaeological investigations
of cave sites, with a special focus on cave bears
in southern Europe and western Asia. The rich literature
on moder brown and black bears (U. americanus)
plays a key role in this kind of research. Specifically,
wildlife data are used to build testable predictions about
how bears may contribute to faunal assemblage formation.
The faunal patterns inside caves that can be explained
by modern bear behavior are played against
anthropological hypotheses about ancient human behavior.
A variety of analytic techniques are marshaled for
this kind of research, including osteometry, skeletal damage
analysis, taxonomic and body part profiling, and
mortality and isotope analyses, to obtain rigorous, if indirect,
evidence about Pleistocene cave bear (and human)
ecology. For related publications see Stiner (1994, 1998)
and Stiner et al. (1996, 1998), and for information on
Pleistocene carnivore guilds in the Mediterranean Basin,
see Stiner (1990, 1991, 1992, 1993, 1994) and citations
therein.

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Continued....

HISTORY OF HOMINID-URSID
COEXISTENCE
Between 1.8 and 1.4 million years ago, populations of
a hominid known as Homo ergaster expanded from Africa
into Eurasia. Hominids' spread across southern Asia
appears to have been rapid (Klein 1989). Colonization
of continental Europe and the colder regions of northcentral
and eastern Asia by hominids took considerably
longer, but they certainly reached these regions before
500,000 years ago. The first hominids to enter Eurasia
were omnivores with a notable capacity for hunting vertebrate
prey, a property which may have been essential
to winter survival in northern habitats (Foley In Press,
Stiner In Press). Colonization of new continents put
hominids in contact with diverse environments and novel
floras and faunas.
Hominids were late arrivals to the predatory guilds of
Africa, where they first evolved, and hominid-camivore
interactions must have intensified as meat-eating exposed
hominids to interspecific competition. Hominids were
late arrivals to predator guilds, yet again, as they invaded
Eurasian ecosystems characterized by winters of intense
cold, lasting snow cover, and seasonally scarce food. In
addition to habitual flesh-eaters, the process of colonization
brought hominids together with 2 widespread omnivorous
genera of the northern hemisphere-pigs (Sus
spp.) and bears (Ursus spp.). The ancestral bear of Lower
Middle Pleistocene (U. etruscus) was relatively smallbodied
but evolved into larger types by the Middle Pleistocene.
This presentation concerns 2 bears in particular,
cave bears (U. deningeri, U. spelaeus, U. rossicus) and
brown bears (U. arctos and its most immediate ancestors)
(Kurten 1976, Baryshnikov 1998). Once prevalent
throughout Eurasia, all cave bears were extinct by roughly
10,000 years ago (Baryshnikov 1999), and most populations
disappeared considerably earlier. Brown bears continue
to exist and even doubled their geographic range
during the Late Pleistocene by colonizing the Americas,
as did humans not long thereafter.
Because recent humans and bears display strong attractions
to meat as well as to energy-rich plant foods,
their evolutionary histories following biogeographic contact
must have affected one another to some extent. The
ecological links between humans and bears may always
have been relatively weak, because both tend to be versatile,
generalist foragers (sensu Foley 1984). These links
were perennial, however, due to overlapping needs for
foraging territory and, periodically, for shelter.

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PLEISTOCENE HUMAN-BEAR
INTERACTIONS: FACT AND FICTION
There is no shortage of bear stories in anthropological
and popular literature. Most of them concern "cave men"
(Neandertals) and cave bears. The original site for the
Neandertal cave bear cult is Drachenloch Cave in Switzerland,
made famous by Bachler's radical interpretation
of a fauna consisting almost exclusively of bear bones
(Kurten 1976). The sediments of Drachenloch lacked
artifactual material, but allegedly preserved a stone crypt
with as many as 7 cave bear skulls arranged neatly inside
and, nearby, a smaller stone chest packed with bear
long bones. Bachler's claim was refuted by Koby (1940)
and in Kurten's (1976) highly entertaining book, The
Cave Bear Story (also Kurten 1958, 1971, 1973).
The cave bear cult is a engaging story, if only for the
early spiritualism it implies. The idea that archaic humans
manipulated bear remains in symbolic ways persists,
at least partly because bear bones frequently occur
with stone artifacts in other Paleolithic cave sites. Cut
marks or burning damage have been found on a few bear
bones in Middle and Upper Paleolithic sites (Barta 1989,
Stiner 1994:109-123), although examples are rare overall.
Bear images also figure in the earliest known art of
the Upper Paleolithic in western Europe, but these cases
date to no earlier than 32,000 years ago (Chauvet et al.
1996). Many sedimentary associations of bear bones and
Paleolithic stone artifacts are much older, and one of the
oldest examples of all comes from Yarimburgaz Cave,
Turkey.
In 1992 I was invited by F Clark Howell (University
of California-Berkeley) and Giiven Arsebtik (Istanbul
University) to work on a large, well-preserved fauna that
they had excavated from the Middle Pleistocene layers
in Yarimburgaz Cave. The site is >250,000 years old
(Blackwell et al. 1990, Farrand 1992, Kuhn et al. 1996,
Stiner et al. 1996, Santel and von Koenigswald 1998),
dating to well before the appearance of anatomically
moder humans or Upper Paleolithic cultures anywhere
in the world. The formation history is complex, and the
deposits are rich in cave bear remains (Ursus deningeri)
(Table 1) and just under 1,700 Paleolithic stone artifacts
(Fig. 1; Kuhn et al. 1996). Also present in low frequencies
are fragmentary remains of a diverse array of ungulate
and non-ursid carnivore species (Table 2).
Only a few of the ungulate remains have cut marks
(<1%) from Paleolithic stone tools. Gnawing damage is
present on many more of the ungulate bones as well as
on bear and non-ursid carnivore bones (Fig. 2). Bear
remains were least affected by gnawing carnivores, however,
and they are the only remains that were also gnawed
significantly by small rodents (Table 3). Stone artifacts
and the bones of bears, ungulates, and non-ursid carnivores
are scattered together in the Middle Pleistocene
layer (Fig. 3, Table 4). The candidates responsible for
bone collection and modification in this site are hominids,
wolves, spotted hyenas, and cave bears. Signs of
each candidate are evidenced by the presence of stone
artifacts or skeletal representation in the species profile.

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INTERPLAY BETWEEN RESEARCH ON
MODERN AND PLEISTOCENE BEARS
One of the most troubling questions about the
Yarimburgaz Cave assemblage is why so many bear bones
occur with the Paleolithic artifacts. One hypothesis proposes
that the bear deaths resulted from non-violent
causes in the context of hibernation, implying that bears'
presence in the cave was not linked in time to human
activities there. Alternatively, the bears may have been
hunted by humans, among other predators, implying that
the spatial proximity of bear bones and stone artifact belies
a temporal and causal link between them.
To address these hypotheses, one first needs to know
(1) whether cave bears were hiberators, and, if so, (2)
whether bears would collect bones of prey in dens, and
(3) the likelihood that bears would use caves for either
purpose. Constructing test implications for these and
other propositions begins by necessity with information
on moder bears (Stiner et al. 1996, 1998; Stiner 1998).
Ursus deningeri is extinct, of course, but some of the
behavioral tendencies documented for moder Ursus help
establish what was possible in the past. The material
correlates of these behaviors can also be modeled over
the long term. Important aspects of cave bear ecology
are expressed by the isotopic contents of tooth enamel,
patterns of bone damage, skeletal element representa
tion, and element completeness. Information on the
dominant causes of death and feeding habits can be inferred
from the mortality pattern (age structure) of the
fossil population based on tooth eruption, wear, and
breakage. Adult sex ratios and size dimorphism between
the sexes can be determined from osteometric measurements.

Models in the Absence of Complete
Analogs
Cave bears, an extinct subgenus (Spelearctos) of
Ursidae, were versatile enough to inhabit large areas of
Eurasia during the Middle and Late Pleistocene. Yet
cave bears had evolved a specialized dentition with large
chewing surfaces and powerful chewing muscles. Their
multi-cusped, bunodont dentitions emphasized crushing
and grinding functions and imply a heavy dietary reliance
on tough, fibrous plant foods (Koby 1940, Kurten
1976:11-26, Baryshnikov 1998, Stiner et al. 1998). Isotope
studies have yielded conflicting results on cave bear
diet, however (Bocherens 1994, Hilderbrand et al. 1996,
Stiner et al. 1998). Much of the controversy stems from
contradictions that taphonomic and morphologic evidence
pose to the isotope results (Mattson 1998, Stiner
et al. 1998). It is likely that cave bear habits varied in
response to environmental circumstance, but the limits
on their abilities to do so remain unknown. Pleistocene
cave bears shared with other bears a general tendency
toward omnivory, but their dental adaptations reached a
morphologic extreme and testify to a great dependence
on seasonal plant foods. This fact, along with the oftnoted
prevalence of cave bear skeletons in the Pleistocene
sediments of Eurasian caves, make a strong case for cave
bears as hiberators (Kurten 1958, 1976).
Although distinct species, modem black and brown
bears have much in common biologically, including hiberation
behavior and its nutritional and reproductive
contingencies (Garshelis and Pelton 1980; Johnson and
Pelton 1980; Nelson et al. 1980; Rogers 1981, 1987; Tassi
1983; Murie 1985; Clevenger et al. 1987; Clevenger
1990, 1991; Hellgren et al. 1990; Clevenger and Purroy
1991). These basic similarities permit a few generalizations
about the relations between bear diet and hibernation
behavior, hibernation-related mortality, and the
criteria governing den site choice. The metabolic and
reproductive aspects of hibernation in moder bears are
thought to be intrinsic (Johnson and Pelton 1980,
McNamee 1984:253-257, Watts et al. 1987, Watts and
Jonkel 1988, Hellgren et al. 1990). We may assume that
these qualities are unlikely to have been profoundly different
in Middle and Late Pleistocene cave bear populations.
The mortality that normally accompanies
hibernation in bears therefore should be comparable as
well.

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Continued....
Do Bears Den in Caves?
Even if one accepts that cave bears were hibernators,
we are left to explain their presence in caves. The abilities
of modern bears to make artificial shelters are well
known, and excavated dens are the norm in many study
areas (e.g. Rogers 1981, Kolenosky and Strathearn 1987,
Schwartz et al. 1987, Mack 1990, Miller 1990, Hayes
and Pelton 1994, Smith et al. 1994). However, wildlife
studies from Europe and North America show that modern
bears willingly hibernate in natural caves and fissures
where these conveniences are present (Murie
1985:133-135, Clevenger and Purroy 1991:113-123,
Hayes and Pelton 1994). The prevalence of bear remains
in Pleistocene cave sediments is not necessarily explained
by heavy use of them over earthen dens in the past; limestone
caves and fissures are merely better preservation
environments for the bones of deceased bears.

Do Bears Collect Bones of Prey in Dens?
Carnivore species that rely on natural or excavated
shelters seem to divide into 2 behavioral categories: bonecollectors
and non-collectors. Many of the canids and
hyaenids deliberately gather bones at den and rest sites
(Mech 1970, Kruuk 1972, Ewer 1973, Fentress and Ryon
1982) and may amass great quantities of prey bones in
some cases (Hill 1980, Binford 1981). Hominids did
essentially the same at residential sites during the Pleistocene,
sometimes in caves. The habits of bears are quite
different, however. Wildlife accounts show that black
and brown bears do not normally carry food of any sort
to dens, and they consume little food while preparing
their winter beds (McNamee 1984, Rogers 1987:23).
Bears often mound piles of inedible vegetation in hibernation
dens (McNamee 1984:252-253, Murie 1985:133-
135, Manville 1987, Rogers 1987:20-22, Clevenger
1991, Smith et al. 1994), but bones other than those of
unlucky bears generally are not found.
The location of a den is secret (Kolenosky and
Strathearn 1987, Mack 1990, Hayes and Pelton 1994),
because sleeping bears are vulnerable to attack despite
their great size (Kurten 1976, Tietje et al. 1986, Rogers
1987:53, Ross et al. 1988). Predation on denning bears
by wolves, humans, and other bears is well known, as is
cannibalism within and between bear species (LeCount
1987, Mattson et al. 1992). Food debris in and around
dens would betray the location of a hibernating bear to
predators and presumably conflicts with the bear's need
to remain hidden. The only exception to this generalization
that I have found is reported by Rogers (1987:23),
a single case in which a lactating female black bear found
a deer carcass near her den in spring and dragged it into
the den. It is reasonable to generalize, therefore, that the
quantities of non-bear bones that might accumulate in
bear dens are nominal, if perceptible at all, from a paleontological
point of view.
Yet the bones of a variety of large mammals are found
in Pleistocene cave sites that also contain the bones of
bears. This is true of Yarimburgaz Cave, for example, a
fact which is explored in some detail below. Information
on moder bear behavior nonetheless suggests that
other species must be responsible for the presence of nonursid
bones. The presence of scant remains of canids
and hyaenids in the Yarimburgaz species profile is quite
significant in this regard.

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BEAR BODY PART PROFILES AND
BONE DAMAGE PATTERNS
Bears are likely to contribute their own remains to the
sediments in hibernation dens, even if new bodies are
added only sporadically over many generations of bears.
In these circumstances all of a bear's skeletal parts should
be present in an earthen or rock shelter, because the bear
dies in place. The situation is quite different for large
mammal body parts ported to the shelter by carnivorous
occupants, because these food items are obtained elsewhere,
are divisible, and are subject to transport costs.
Body parts normally are moved to safe havens piece-meal
by predators such as wolves and hyenas (Stiner 1991,
1994). Although herbivores are the principal prey of
large carnivores, inter- and intra-specific aggression
nearly guarantees that parts of some carnivore carcasses
will accumulate along with herbivore bones in the dens
and rest sites of hyaenids and canids. If the site is used
for reproductive purposes, the skeletons of young canids
or hyaenids may also become part of the paleontologic
record, though seldom as complete bodies (Stiner 1994).
Unless a bear carcass is extensively fed upon, its skeletal
parts should remain inside the cave. However, bear
skeletons in den sites may not stay in articulatory order,
because any bear that later dens in the cave would renovate
the bedding area (Reynolds et al. 1976, Judd et al.
1986). The scale of this kind of disturbance hinges on
the frequency with which a shelter is re-used by bears
and the rate of sediment accumulation (Kurten 1976,
Stiner 1994, Stiner et al. 1996). In the Middle Pleistocene
layer of Yarimburgaz Cave, the total bear assemblage
computes to a pattern of nearly complete skeletons,
but the components of these skeletons are scattered in a
nearly random fashion. The remains of ungulates and
non-ursid carnivores are far less complete and also scattered
(Stiner et al. 1996)
Gnawing damage on the bear bones, though less frequent
than on other large mammal remains, suggests
additional reasons why bear remains are scattered
throughout the Middle Pleistocene layer. Denning bears
that perish from predation may be fed upon by their attackers.
But the decaying body of a bear that died from
nonviolent causes will attract scavengers, often the same
species known to attack bears in other circumstances. It
therefore is difficult to distinguish between deaths resulting
from attacks on live, dormant individuals from
post-mortem scavenging on the basis of gnawing damage.
Many of the gnawing traces can be attributed to
wolf- or hyena-sized carnivores and, less often, to larger
bears (Fig. 2).
The observations above raise questions about how the
Yarimburgaz cave bears died, but they do not answer
them. Gnawing damage on bear remains-or cut marks
in other cases-is not proof of hunting. Such damage
only indicates consumption or related use of carcasses.
However, bear bones were less frequently damaged by
carnivores than were the remains of ungulates and nonursid
carnivores, and rodent damage shows the opposite
distribution. These observations lend some support to
the hypothesis of temporal and causal independence be
tween the bear remains and other materials in
Yarimburgaz Cave. The mortality pattern of the bears
has greater potential for distinguishing the circumstances
of bone damage, specifically between hunting and scavenging
contexts (Stiner 1998).

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Causes of Cave Bear Mortality
It is clear from the wildlife literature that hibernation
dens are places where brown and black bears occasionally
die (Kurten 1976; Garshelis and Pelton 1980; Rogers
1981, 1987). Of course, hibernating bears may perish
from violent or nonviolent causes inside dens, just as
they do in free-ranging contexts. Hunting of hibernating
bears is well known among traditional human cultures
of the 19th and 20th centuries (Kurten 1976, Rogers
1981:69, Ross et al. 1988, Binford In Press). Bear hunting
is not a common practice among any of these cultures
and probably could never be so because bear
populations are relatively unproductive (Craighead et al.
1976, Glenn et al. 1976, Bunnell and Tait 1981:77).
Humans' ability to hunt hibernating bears with traditional
technology (Binford In Press) nonetheless suggests
that hunting must be considered a potential cause of bear
mortality in dens in the past.
The unique biology of moder bears suggests that relatively
distinct mortality (age structure) patterns will arise
in hibernation dens from predominantly violent versus
predominantly nonviolent causes. These differences in
mortality patterns can be used to test the cave bears' connection
to prehistoric human activities in the same shelter.
The net expectation for the cave bear population
using winter dens should resemble the living age structure
of the total free-ranging population, because (1) all
reproducing adult females must hibernate to rear their
cubs, (2) reproductive rates in bears are low, and (3) other
adult bears may also hibernate if the population is relatively
vegetarian, as appears to have been true for cave
bears.
The living age structure of bears that use hibernation
dens each year therefore serves as the model for predation
on cave bears by den raiders (Stiner 1998): primeaged
adult females, old adults, infants, and adolescents
should be affected randomly by hunting and therefore be
represented in the death assemblage in proportion to their
living abundances (Fig. 4). Repeated hunting of denning
bears should be indifferent to the ages of the individuals
occupying dens for at least 3 reasons. First, there
is little opportunity for attackers to survey individual
vulnerability while hunting encrypted prey. Second, adult
females normally accompany hibernating juveniles in
their first, second, and even third winters of life. Finally,
it seems that all members of the denning cluster
are subject to attack (Garshelis 1994), presumably because
young bears are easy victims and their mothers are
likely to become aggressive in tight quarters. Reports of
intraspecific killing are comparatively few, but adult female
bears, often with young cubs, are among the individuals
that perish during den attacks (on black bears,
Garshelis 1994:3; Rogers 1987). The cumulative mortality
pattern resulting from attacks on hibernating bears
should differ from age-dependent mortality in free-ranging
bears because individual characteristics can be perceived
in the latter situation and the attackers will tend
to gravitate toward young, weak, and old victims. The
expectation of a relatively nonselective age structure for
bears attacked inside dens (though poor in adult males,
Garshelis 1994, McLellan 1994) is largely theoretical,
however, as too few data are currently available to con
struct real mortality patterns with statistical confidence
(Garshelis 1994).
The alternative age structure model for bear mortality
in dens is the classic one of attritional death from malnutrition,
disease, and senescence, a pattern typical for
mammals in general (sensu Caughley 1977; on bears see
reviews by Kurten 1958, Stiner 1998). An attritional
death pattern affects young and old age groups preferentially.
Because prime-aged adults are conspicuously under-represented
relative to their living abundance, an
attritional mortality pattern displays a bimodal or Ushaped
distribution in histograms. Non-violent mortality
in moder bears is relatively high toward the end of
the hibernation period if bears are in poor condition, although
starvation is most common in moder populations
that are not extensively hunted (Kurten 1976;
Garshelis and Pelton 1980; Rogers 1981, 1987; McNamee
1984). Bears awaken early if their energy stores are depleted
and may, as a last resort, make short forays in
search of food. Females with cubs tend to stay around
dens longer, both in dormancy and following first emergence
in spring (Miller 1990). Starving or ill bears sometimes
collapse and die in the vicinity of winter dens,
although this is relatively rare (Garshelis 1994, McLellan
1994). Occasional deaths of this sort nonetheless can
add up to many bodies over millennia.
The main difference between the 2 den mortality models
is the near absence of prime-aged adults in the
attritional (nonviolent death) model. To test the hypothesis
for the paleontological cave bear population from
Yarimburgaz Cave, cheek teeth were age-scored based
on their eruption and occlusal wear status (Fig. 4; Stiner
1998). The Yarimburgaz cave bear sample displays an
attritional (U-shaped) death pattern, exemplified by results
for the lower second molar (Fig. 4). The mortality
results for the Yarimburgaz bears generally support the
nonviolent model of bear deaths and refute the violent
model. This result, along with the complete absence of
tool marks or burning damage on cave bear bones, suggest
that the bear deaths in the cave were entirely independent
of hominid activities there. Because the
hypothesis that most of the bear deaths occurred from
hunting is refuted, the possibility of a consistent temporal
or causal link between cave bears and humans at this
site is also refuted. Wolves or hyenas may have been
responsible for a minor fraction of the bear deaths, but
much of the gnawing on bear bones by hyenas and wolves
appears to have occurred from scavenging.
An interesting detail of the mortality pattern for the
Yarimburgaz cave bears is the pronounced peak in the
late juvenile age stage III (Fig. 4). The death peak probably
represents the winter when cubs became independent
of their mothers. The pattern is similar to a condition
noted in some modern bear populations (Glenn et al.
1976, Bunnell and Tait 1981). While the stage III peak
is a relative measure and can not be tied to an exact age
in real years, it suggests relatively long periods of offspring
dependency, such as is seen among moder brown
(as opposed to black) bears. The transition to independent
life is associated with elevated mortality, often from
predation by dominant adult males. Cave bears were
much like moder brown and black bears in this regard.
The low peak in the youngest age cohort (stage I) may be
explained partly by complete ingestion of small cubs by
predators or scavengers (Stiner 1998), but the relative
frequencies of individuals in cohorts II and III can not be
explained away, because the cubs would have been much
larger and their bones more robust.
To summarize thus far, information on species representation
in the Yarimburgaz fauna and the patterns of
bone damage, body part representation, and mortality for
the cave bears indicate that most or all of the cave bear
remains are causally unrelated to hominid presence at
the same site. The bear bone accumulations resulted primarily
from nonviolent mortality associated with hibernation
over many generations of den use. Attacks on
living bears may also have occurred, but this appears to
have been uncommon. Canid and hyaenid contact with
bear carcasses certainly is indicated by gnawing damage
and scatological bone containing bear cub and hare (Lepus
sp.) remains (see Stiner et al. 1996). Direct contact between
cave bears and humans at this site is unlikely.
The faunal and artifactual evidence shows that at least
3 distinct biological agencies contributed to formation of
the Middle Pleistocene faunas: hibernating bears, nonursid
carnivores such as wolves, and hominids, in descending
importance. The Yarimburgaz faunas represent
overlays of many short-term deposition cycles, most of
which were unconnected in time. The close spatial associations
of diverse biogenic refuse from bears, wolves,
hyenas, and humans are best explained by slow or uneven
sedimentation inside the cave. Considerably more
can be learned about the habits of the Yarimburgaz cave
bears from other aspects of their skeletons.

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CAVE BEAR DIET: EVIDENCE FROM
TOOTH DAMAGE, ADULT SEX RATIO,
AND STABLE ISOTOPES
Adult Sex Ratio in Dens and Its Relation
to Diet
Hibernation is a bear's strategy for raising exceptionally
altricial infants and enduring food scarcity in winter
(Ewer 1973; Garshelis and Pelton 1980; Rogers 1981,
1987; Tassi 1983; McNamee 1984; Murie 1985;
Clevenger et al. 1992). In moder bears, the importance
of hibernation to both sexes increases with the
population's dependence on seasonal foods. And the
probability of either sex dying in dens is partly a function
of time spent in these places.
Mother bears must hibernate for several months before
cubs are mobile (Johnson and Pelton 1980). In contrast,
adult males and barren females need only hibernate
as long as food is unavailable (Johnson and Pelton 1980,
Rogers 1987:20-24, Schwartz et al. 1987, Hellgren et
al. 1990:291, Miller 1990, Van Daele et al. 1990, Smith
et al. 1994, Weaver and Pelton 1994). One key to adult
brown bear sex ratios in dens appears to be winter meat
from large game (Picton and Knight 1986) available dur-
ing the months when bears can not find foliage, plant
mast, tubers, invertebrates, and most small vertebrates.
The degree to which adults other than pregnant females
depend on seasonally available foods therefore affects the
adult sex ratio of the hibernating population. Males of a
relatively herbivorous population should have hibernation
times approaching those of pregnant females, less if
reliable food sources can be found in winter.
The adult sex ratio of a bear population also is subject
to considerable imbalance independent of who hibernates
and who does not, often favoring adult females
(Craighead et al. 1974, Rogers 1987). This means that
the standard against which bear sex ratios in dens are
evaluated must be tempered by a consideration of the sex
structure of the total adult population from which the
death assemblage derives. The adult sex structure of
ancient cave bear populations can not be known absolutely,
but it can be inferred in relative terms from indirect
evidence. Bear sex ratios in the population at large
tend to be even at birth (Rogers 1987, Kolenosky 1990,
Miller 1994), but sex ratios normally are skewed in favor
of females in adulthood (for black bears, Rogers
[1987] reports M:F 1:2; for brown bears, Smith [1990]
reports M:F 1:3; Clarkson and Liepins [1994] M:F 1:2).
Because black bears are highly omnivorous and may
hibernate for up to 7 months (Kolenosky and Stratheam
1987, Schwartz et al. 1987, Miller 1990, Smith et al.
1994)-among the longest hibernation times for bears
(Miller 1990)-a similar sex ratio in a paleontological
population of any bear species would imply a heavy dependence
on plant and invertebrate foods. A greater dietary
emphasis on large mammals (scavenged or hunted)
or Pleistocene habitats characterized by mild winters instead
should result in substantially greater differences
between pregnant female and adult male hibernation
times (Kolenosky and Strathearn 1987, Miller 1990, Van
Daele et al. 1990, Weaver and Pelton 1994), and, consequently,
the overall probabilities that the bones of each
sex will become part of fossil assemblages in caves.
Modem polar bears, which are fully carnivorous and live
in very cold regions, represent the opposite extreme which
proves the rule: adult males may not hibernate at all and
therefore would seldom if ever die inside ice dens (M/F
0:100).
Using an adaptation of Gordon and Morejohn's (1975)
metric technique, the sex ratio of the adult cave bears
from Yarimburgaz Cave is estimated to have been 73
males for every 100 females (Stiner et al. 1998). All
juvenile individuals were eliminated from this comparison
because the naturally even sex ratio at birth in bears
is bound to push the total population pattern toward evenness,
independent of that population's foraging habits.
The sex ratio of cave bear samples from Europe varies
between 30:100 to 100:100 males to females, but there is
a tendency toward evenness in adult sex ratios overall
(summarized in Kurten 1976:76-77). The sex ratio of
the Yarimburgaz cave bears from Turkey therefore is consistent
with the pattern found for the European cave bear
samples.
It is interesting that the sex ratio of adult cave bears
lies at one extreme of the full range of possible patterns
in Ursus. The mild female bias in the Yarimburgaz cave
bears falls well beyond the range typical of moder bears
in general and may best resemble that of highly omnivorous
black bears. The sex ratio of the cave bears suggests
2 important things about them: (1) the living
population was not poor in adult males in Turkey or elsewhere;
and (2) these animals depended very heavily upon
seasonal food resources. The sex ratio specifically contradicts
the possibility of a regular, heavy emphasis on
large game. Whether cave bears were firmly at the vegetarian
end of the dietary continuum in every region where
their remains are found is unclear, but a dedication to
highly seasonal food sources is indicated by the adult
sex ratio, dental morphology, and damage to the teeth
(below).

[brobear]

from post #50...

Tooth Damage and Feeding Habits
The cave bear's dental specializations include cheek
teeth with many cusps, large occlusal surfaces in relation
to crown height, and a cranial architecture mechanically
suited to grinding and crushing (Kurten 1976:18,
Baryshnikov 1998). The extent of occlusal wear in cave
bear molars is exceptional relative to that seen in brown
bears: molar crowns were often completely obliterated
in old cave bears across the many regions where they
have been studied. Among elderly cave bears from
Yarimburgaz, several first and second molars were worn
to stubs and the pulp cavities fully exposed prior to death.
The damage to cave bear cheek teeth corroborates routine
consumption of tough plant materials such as nuts,
hard-coated seeds, tubers and other roots, berries, foliage,
and the like. Mattson (1998) reached a similar conclusion
about cave bear feeding habits based on
interspecific morphometric comparisons of modern and
Pleistocene bear crania (i.e., a heavy emphasis on root
grubbing).
Koby (1940, 1953) noted peculiar wear and breakage
patterns on the anterior teeth of some European cave
bears. Many of the Yarimburgaz cave bear canines likewise
were broken or chipped during life and worn through
continued use. These and other anterior teeth were also
seriously damaged by interstitial wear and abrasive forage.
Of the ageable adult canines that had come into
wear by the time of death, 31% had been broken in some
way. Some modern brown bear populations also display
peculiar wear on and frequent breakage of the canines
(A. Clevenger, Banff National Park, Alberta, Canada,
personal communication, 1995).
The frequency of adult canine breakage is very high
relative to that observed by Van Valkenburgh and Hertel
(1993) for modem and Late Pleistocene carnivores of
North America, where this phenomenon was related to
bone feeding and feeding competition. The relative incidence
of canine breakage in the Yarimburgaz cave bear
sample is amplified somewhat by the advanced ages of
the adults therein, but this bias does not wholly account
for the high frequency of damaged canines. The biomechanical
argument of frequent asymmetrical loading on
the canine teeth (Van Valkenburgh and Hertel 1993) probably
also applies to the Eurasian cave bears, but the dietary
causes of the damage probably do not. The
unusually high frequency of damage to the anterior teeth
in cave bears is distinctive (B. Van Valkenburgh, University
of California, Los Angeles, California, USA, personal
communication, 1998) and suggests habitual
contact with and levering of hard matter. Intraspecific
competition may have added to the damage wrought by
feeding. The extreme wear and breakage to the front
teeth (canines and incisors) of adult cave bears from
Yarimburgaz Cave suggests that food frequently was obtained
from cryptic sources requiring actions such as digging
and prying (Baryshnikov 1999, Stiner et al. 1998).

[brobear]

from post #51...

Isotope Signals in Bear Tooth Enamel
Quade, Pigati, and Achyuthan of the University of
Arizona examined the carbon and oxygen isotopic composition
of the enamel of cave and brown bear teeth from
Yarimburgaz Cave (Stiner et al. 1998) to address questions
about dietary preferences, such as between marine
and terrestrial sources, and whether the signals obtained
from cave and brown bear teeth differ. Tooth enamel
was preferred over other skeletal materials for this study
on grounds that its dense, coarsely crystalline structure
tends to preserve an original paleodietary signal better
than do the less dense mineral structures of bone and
dentin (Lee-Thorp and van der Merwe 1987, Lee-Thorp
et al. 1989, Thackeray et al. 1990, Quade et al. 1992).
Twenty-three teeth were analyzed, 21 from cave bears
and 2 from brown bears. The carbon analyses yielded a
mean 813C value of -15.1?0.7?/0o and a range of -14.1 to
-16.4. The results from the brown bears, although from
only 2 teeth, were essentially indistinguishable from those
for the cave bears. The oxygen analyses indicated an
average value of -6.5+1.00?/ in 6180 and a range of -4.9
to -9.0. The fossil bear teeth from Yarimburgaz Cave
retained an unaltered carbon isotopic composition very
similar to that of moder herbivores and carnivores living
in regions dominated by C3 vegetation, such as around
the Mediterranean Sea today. Marine resources were not
an important component of the diets of the Yarimburgaz
bears, even though Yarimburgaz Cave was situated in a
near-coastal setting during the Middle Pleistocene.
The carbon isotope results for the Yarimburgaz bears
closely match measurements from some cave bear
samples in western Europe (Bocherens et al. 1994,
Hilderbrand et al. 1996). Bocherens et al. (1994) obtained
613C values on cave bear apatite of -14.8?0.7?/
(n = 15), remarkably close to those of the Yarimburgaz
bears at -15.1?0.60?/ (n = 21). Such concordance suggests
that the dependence of cave bears on terrestrial food
sources was geographically widespread. However,
Bocherens et al. (1994) and Hilderbrand et al. (1996)
disagreed on the extent of herbivory in cave bears as evidenced
by nitrogen isotope measurements. Our isotope
results cannot speak directly to this issue, as carbon isotopic
values are not good discriminators of trophic level
and the protein sources of nitrogen probably are not preserved
in the Yarimburgaz specimens due to their great
antiquity. Other sources of information on the
Yarimburgaz cave bears do speak to this issues: adult
sex ratios in dens and dental evidence contradict a high
degree of carnivory in the Middle Pleistocene sample from
Turkey as well as for other fossil cave bear populations.

[brobear]

SEXUAL SIZE DIMORPHISM IN CAVE
BEARS
Moder bears exhibit comparatively high levels of size
dimorphism between the sexes. Grossly analogous differences
in adult stature and weight have been inferred
for Pleistocene Ursus species of the northern hemisphere
based on the dimensions of canine teeth and weight-bearing
limb bones (e.g. Koby 1949; Kurten 1958, 1976).
The results on the Yarimburgaz cave bears (Stiner et al.
1998) are based on measurements of carpal or wrist bones
(pisiform and scapholunate; Stiner et al. 1998), using
Josephson et al.'s (1996) method-of-moments (MoM)
technique. This technique assumes that the total distribution
of a metric trait is composed of 2 underlying normal
distributions, one for males and one for females.
Three moments around the mean of the combined-sex
distribution are used to estimate the means and the common
standard deviation of the 2 underlying distributions.
The scale of measurement most easily controlled in paleontological
studies is a simple linear one and, to some
extent, areal measurements computed therefrom. If the
Yarimburgaz size data are extrapolated to yet a third scale
of measurement, analogous to body volume or mass, adult
male cave bears would have been roughly twice the lean
body weight of adult females. This level of sexual size
dimorphism is relatively extreme among terrestrial mammals,
but not unusual among large-bodied populations
of modem brown bears. We infer from this that their
mating system was similar to that of extant Ursus species.

[brobear]

HOW DID COEXTANT CAVE AND
BROWN BEARS DIFFER?
Osteometric techniques demonstrate the presence of 2
Middle Pleistocene bear species in the Middle Pleistocene
deposits of Yarimburgaz Cave-Ursus (Spelearctos)
deningeri, a large cave bear, and U. arctos or brown
bear-the former abundant and the latter rare. Acknowledging
potential time-averaging effects on fossil assemblages,
it nonetheless seems that cave and brown bears
coexisted in many areas of Eurasia. Cave bears may have
been more prevalent in some regions and periods, possibly
at the expense of brown bears, and vice versa.
Brown bear teeth from Yarimburgaz Cave are easily
distinguished from cave bear teeth on the basis of size.
The only brown bear tooth in the M2 sample, for example
(Fig. 5), falls well below the maximum (mean) proportional
size difference that can be expected between the
sexes in any terrestrial mammal (roughly males/females
= 1.45-1.50 by a linear standard), even in highly size
dimorphic lineages such as bears or the great apes
(Pongidae). The other 64 data points form a single cluster
(Fig. 5), representing a continuous distribution of male
and female cave bear tooth measurements. In addition,
an informal comparison of the fifth metacarpals of a
mature cave bear and a mature brown bear from
Yarimburgaz Cave (Fig. 6) exemplifies dramatic structural
differences between the 2 species. The brown bear
metacarpal is only somewhat shorter than that of the cave
bear, but the difference in robusticity is great.
The limb allometry of cave and brown bears also differed.
Cave bears possess relatively shorter distal limb
elements and longer upper elements than is typical in
brown bears (Kurten 1976, Mattson 1998). The cave
bear build is interpreted to have emphasized strength over
agility or a quick gate, whereas brown bears are relatively
fast runners over short distances. Tooth morphology
testifies further to differences among brown and cave
bears, not least of which were the extraordinary milling
capabilities evidenced in the latter. The hyper-developed
dental architecture of the cave bear is arguably among
the most telling feature in its ecology, as it is expressed
by highly conservative elements in the evolution of mammalian
skeletons-molar and premolar teeth.
The evolutionary effects of limiting similarity are expressed
in the bone and dental structures of cave and
brown bears. It is interesting in light of this that we
cannot distinguish the diets of coextant cave and brown
bears in the Yarimburgaz sample on the basis of carbon
and oxygen isotope analyses. The isotope data do yield
some insights on the diets of cave bears, but these approaches
may lack much of the resolution required to
differentiate between coextant cave and brown bear diets;
perhaps many of the dietary differences exist within
the food categories compared by isotope studies (e.g.,
among C3 plants). In addition to anatomical differences,
cave bear hibernation sites tend to be concentrated at
relatively high altitudes, thus accounting for their high
density in the moder countries of Switzerland and Austria
(Rabeder and Nadel In Press). Cave bears were not
confined to highlands-their remains also occur in caves
at sea level in low frequencies (e.g. Stiner 1994)-but
brown bear remains seem to be more common at lower
altitudes, as are human archaeological sites dating to
before the Upper Paleolithic period.

[brobear]

DISCUSSION
Cave bears inhabited a vast area stretching from western
Europe to the Urals, Siberia, and into west and cen
tral Asia; their Pleistocene distribution was considerably
greater than was previously supposed (Kurt6n 1976;
Baryshnikov 1989, 1996, 1998; Tchernov and Tsoukala
1997; Stiner et al. 1998). Cave bears coexisted with
brown bears and early humans throughout most or all of
this range during the Middle and Late Pleistocene. The
classic cave bear form appears in the fossil record roughly
700,000 years ago and persists in many areas until the
Last Glacial Maximum, 18,000 years ago, and until the
end of the Pleistocene (10,000 years ago) in refugia of
the Trans-Caucasian highlands (Baryshnikov 1996).
Only the brown bear exists in these and other regions
today. With its eventual colonization of American ecosystems,
the once exclusively Eurasian brown bear enjoys
the widest distribution known for any bear species
in the late historic period (Kurt6n 1971).
Cave and brown bears have a long history of contact
with humans, but evidence for direct interaction is relatively
rare. Of these cases, most of the compelling examples
of direct interaction are between humans and
brown bears. Images of bears are featured in the earliest
art of Europe, beginning some 32,000 years ago in the
Upper Paleolithic. Kurt6n's (1976:91) claim that brown
bears were more often the subject of early art continues
to hold true, even with the recent discovery of the carnivore-rich
imagery in Chauvet Cave (Chauvet et al. 1996).
The relatively few images of cave bears that exist in Upper
Paleolithic cave art-such as in the French sites of
La Colombiere, Les Combarelles, and Chauvet-portray
an animal with an enlarged shoulder hump, accentuated
stop in the nasal bridge, and relatively fleshy nose and
lips. Upper Paleolithic art is not without its fanciful elements,
but some aspects of these paintings may be quite
accurate.
But what about early cases of bear-artifact associations,
dating to before the dawn of Upper Paleolithic cultures
and the earliest preserved art? Taphonomic
investigations of Yarimburgaz Cave and other sites refute
the possibility of causal links between cave bear and
hominid occupations (Prat 1988, Andrews and Turner
1992, Gargett 1996). The close proximity of bear bones,
stone artifacts, ungulate, and non-ursid bones in the
Middle Pleistocene layer of Yarimburgaz Cave reflects
contemporaneity only on a geologic time scale, not at
the scale of mammalian lifetimes or annual cycles. Preserved
records of these events were superimposed, one
directly upon another, because the rate of sediment accumulation
was slow relative to the rate of bone and artifact
accumulation and because of post-depositional
disturbances by bedding bears and other digging carnivores.
Human occupations of the early sites were quite
ephemeral, short visits separated by long intervals of
absence. Under these circumstances, early humans would
have provided few if any deterrents to den-seeking bears.
Despite its long history of use by numerous large mammals,
it seems that Yarimburgaz Cave was often an empty,
quiet place.
The case of Yarimburgaz is one of several windows on
cave bear ecology, as well as early humans' relations with
them. The findings presented here confirm a picture of
cave bears as a relatively herbivorous omnivore, highly
dependent on seasonal food supplies, including plants,
and probably also invertebrates and small vertebrates.
Both sexes of cave bears solved the problem of winter
food scarcity by hibernating. Male and female cave bears
were as size dimorphic as large-bodied populations of
modem brown bears, suggesting similar mating systems,
specifically the degree of male-male competition for
mates. Cave bears were perhaps most different from other
bears in their ability to extract nutrients from tough, resistant,
and often gritty plant tissues. In so doing, old
adults frequently wore their massive molars to pegs, a
condition not unknown in brown bears, but certainly not
as typical nor as widespread among populations. Although
more work is needed on the subject, cave bears
appear to have been terrestrially oriented, even in territories
adjacent to productive seas (Hilderbrand et al.
1996).
As for cave bears' ecological relations with early humans,
we have had to deal first with how archaeological
and paleontological records form and the possibility that
separate biogenic events were recorded surfacially as one.
Knowledge of how moder bears behave and die makes
Paleolithic artifact-bear associations difficult to understand
if taken at face value. Only a cross-disciplinary
perspective, informed by wildlife data on modem animal
behavior and by the nature of sedimentary processes,
allows us to explain this phenomenon. The possibility
of a cave bear cult among the Neandertals has been falsified,
and in its place is a more interesting story of coexistence
between omnivorous lineages whose resource
interests occasionally overlapped.
As omnivores, humans' and bears' options for switching
among alternative food sources have always been
considerable. While it is possible that humans eventually
drove cave bears to extinction, this is not at all certain.
It is not clear, for example, that cave bears competed
directly with humans for food, even if they may have
competed with humans for territory. Human population
densities were very low during most of the Middle Paleolithic
and earlier (Stiner et al. 1999). Human densities
increased during the Upper Paleolithic period, especially
following the Last Glacial Maximum (18,000-20,000
years ago), when cave bears were disappearing from most
areas except certain highland refugia. It is interesting
that the earliest grinding and pounding technology
emerges in Upper Paleolithic cultures, Lilliputian implements
geared first to preparing mineral pigments but later
enlarged and adapted to processing nuts (and eventually
cereals) in some regions by 13-10,000 years ago. Late
Upper Paleolithic humans may merely have expanded
their foraging niche as it was released from competition
by large-molared cave bears, or as favorable plant communities
expanded with climate change.
The intensity of human occupations in natural shelters,
which also increased after 18,000 years ago (Gamble
1986), may have affected these shelters' attractiveness
and availability to denseeking bears. We do not know,
however, if, perhaps owing to their great body size, cave
bears depended more on caves as denning sites than
brown bears. We only know that bones preserve better
in caves than in the open. The necessary links between
caves, cave men, and cave bears are largely of a geological
nature and say little or nothing about the possibility
of habitation and den sites elsewhere on landscapes.
More significant than the possibility of interspecific
competition between early humans and caves bears is
the peculiar nature of cave bear skeletal structure. Cave
bears were a specialized, highly derived type of bear, arising
from a larger lineage which otherwise emphasized
generalized characters. The fact that cave bears specialized
under predominantly glacial conditions (most of the
Pleistocene) itself may provide a more compelling explanation
for their extinction at the beginning of the
modern interglacial (Holocene). The dentition of cave
bears is exceptional for a bear. Specialists are particularly
vulnerable to extinction when the conditions of life
become unstable, and those following the Last Glacial
Maximum, a rapid process of global warming, were
among the most trying for large Pleistocene mammals.
Whatever effect these factors had on cave bears, they did
not affect brown bears in the same way. Brown bears
have retained many generalist features and habits, and
this flexibility no doubt aided their great success in weathering
the Holocene transition.
Wildlife data, such as that on modern bears, are important
referents for zooarchaeological research on the
evolutionary history of human beings as well as on the
species with whom they may have interacted. Archaeologists
do not have the luxury of directly observing the
phenomena that drive our discipline. Through a series
of inferential steps, we extract information from coarse,
imperfect behavioral and morphological records. The
efficacy with which we do so depends on clear expectations
about the relations among key variables, many developed
in the contemporary world, but which also find
expression in fossil animal assemblages. The present
frequently informs research on past. Insights about modem
conservation issues may also be gained from the long
view of humans' relations with coextant species.

[brobear]

ACKNOWLEDGMENTS
I am grateful to M. Pelton (University of Tennessee)
for inviting me to participate in the 1998 IBA meetings
and to A. Clevenger (Banff National Park, Wildlife Section)
for several years of inspiring correspondence on
the subject of bears. I also thank T. Fuller and an anonymous
reviewer for many constructive comments on an
earlier draft of this paper and F.C. Howell, G. Arsebiik,
K. Juell, S. Josephson, J. Quade, J. Pigati, and H.
Achyuthan for their many contributions to the
Yarimburgaz cave bear study.

[brobear]

The scale of measurement most easily controlled in paleontological
studies is a simple linear one and, to some
extent, areal measurements computed therefrom. If the
Yarimburgaz size data are extrapolated to yet a third scale
of measurement, analogous to body volume or mass, adult
male cave bears would have been roughly twice the lean
body weight of adult females. This level of sexual size
dimorphism is relatively extreme among terrestrial mammals,
but not unusual among large-bodied populations
of modem brown bears. We infer from this that their
mating system was similar to that of extant Ursus species.

The cave bear build is interpreted to have emphasized strength over
agility or a quick gate, whereas brown bears are relatively
fast runners over short distances.

( my conclusions )... ( 1 )... Like the grizzlies, male cave bears regularly had to compete with other males violently for a chosen female.
( 2 )... While bears in general are built more for physical strength above speed and agility, this fact is exaggerated in the cave bears. As one Paleontologist once said, "The cave bear is the most bearish of bears" and I agree.

[brobear]

www.reuters.com/article/us-science-bears/genetic-study-implicates-humans-in-demise-of-prehistoric-cave-bear-idUSKCN1V51EL

Genetic study implicates humans in demise of prehistoric cave bear - AUGUST 15, 2019.

WASHINGTON (Reuters) - Genetic research that reconstructed the past population dynamics of the cave bear, a prominent prehistoric denizen of Europe, implicates Homo sapiens rather than climate cooling in the Ice Age extinction of these brawny plant-loving beasts.

Scientists said on Thursday they obtained genome data from 59 cave bears from bones unearthed at 14 sites in France, Germany, Italy, Poland, Serbia, Spain and Switzerland.

Using this, they detected a population downturn roughly 50,000 years ago coinciding with the arrival of our species in eastern Europe and then a dramatic decline starting about 40,000 years ago coinciding with the spread of Homo sapiens throughout Europe. It ultimately went extinct about 20,000 years ago.

The cave bear (scientific name Ursus spelaeus) was one of the charismatic inhabitants of Ice Age Europe alongside animals like the cave lion, woolly rhino, woolly mammoth and steppe bison. It was as big as a polar bear but strictly herbivorous. Firmly in the consciousness of humans in Europe, the bear was depicted in prehistoric cave paintings.

There has been a scientific debate about whether a cooling climate doomed the bears by reducing vegetation central to their diet or whether it was human encroachment including hunting and taking over the caves where the bears hibernated and gave birth.

The steep population decline identified in the study predated climate cooling associated with the most recent Ice Age, said paleogeneticist Verena Schuenemann of the University of Zurich in Switzerland.

The bear’s population also had remained stable for long periods prior to that, including two pronounced cold stretches and multiple other cooling episodes, Schuenemann added.

Homo sapiens originated in Africa more than 300,000 years ago, later spreading worldwide. The study offered fresh evidence that the arrival of Homo sapiens presaged doom for numerous species across Eurasia, the Americas and Australia.

“There is more and more evidence that modern humans have played a determinant role in the decline and extinction of large mammals once they spread around the planet, starting around 50,000 years ago,” biogeologist Hervé Bocherens of the University of Tübingen in Germany said.

“This happened not just by hunting these mammals to extinction, but by causing demographic decline of keystone species, such as very large herbivores, that led to ecosystems’ collapse and a cascade of further extinctions,” Bocherens added.

Before the arrival of Homo sapiens, the bear’s population had remained robust even though it shared its territory with another human species, the Neanderthals, who also went extinct after Homo sapiens invaded Eurasia.

The research was published in the journal Scientific Reports.

[OldGreenGrolar]

www.ancient-origins.net/news-history-archaeology/cave-bear-0012447?fbclid=IwAR2Cf-leUvWvjJVjjNzCH9X4j1hOZm_iOzYV7bZOVktRQRw4Sx_-8MmLGGc

Humans are the cause of cave bear extinction.

[King Kodiak]

Case Closed: 35,000-year-old Murder of a Bear Finally Solved

Paleontologists found the pierced skull of a cave bear in a Siberian cave. It could have been caused naturally – or may have been made for ritual purposes

www.google.com/amp/s/www.haaretz.com/amp/archaeology/case-closed-35-000-year-old-murder-of-a-bear-finally-solved-1.9885375

[brobear]

Jul 29, 2020 3:06:17 GMT -5 OldGreenGrolar said:

www.ancient-origins.net/news-history-archaeology/cave-bear-0012447?fbclid=IwAR2Cf-leUvWvjJVjjNzCH9X4j1hOZm_iOzYV7bZOVktRQRw4Sx_-8MmLGGc

Humans are the cause of cave bear extinction.

Humans A Major Factor In the Extinction of Giant Cave Bears. 
 
Until 25,000 years ago, Europe was home to some of the largest mammals, that ever lived. One of the most remarkable of the megafauna was the gigantic cave bear. Why these massive animals and other megafauna became extinct has been a subject of controversy for decades. Now a genetic analysis of the DNA of the prehistoric cave bear may show that they declined and disappeared because of the arrival of modern humans in Europe and not because of an Ice Age . 

Cave bears (Ursus spelaeus) “roamed Europe for over 100,000 years” according to the New Scientist . They were as large as modern grizzly bears, weighed as much as 2000 pounds (908 kilograms) and were herbivores. A great many remains of the gigantic bears have been found in Central and Eastern Europe.

The last known remains of the extinct cave bear, discovered in a site in the Italian Julian Alps, date to approximately 25,000-24,000 years ago. They were among the last of the megafauna to disappear from Europe.

[King Kodiak]

This is a follow up from reply #17:


Someone stabbed a cave bear in the head with a spear 35,000 years ago



The hole in the parietal bone (left side of photo) matches the cross-section of stone projectile points also found in the cave.


www.google.com/amp/s/arstechnica.com/science/2021/06/someone-stabbed-a-cave-bear-in-the-head-with-a-spear-35000-years-ago/%3famp=1