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Post by Gorilla king on Nov 19, 2021 10:32:23 GMT -5
Large carnivore attacks on hominins during the Pleistocene: A forensic approach with a Neanderthal example
Abstract
Interaction between hominins and carnivores has been common and constant through human evolution andgenerated mutual pressures similar to those present in world-wide modern human carnivore conflicts. This current interac-tion is sometimes violent and can be reflected in permanent skeletalpathologies and other bonemodifications.Inthe pres ent paper, we carry out a survey of 124 forensic cases of dangerous human-carnivore encounters. The objective is toinfer direct hominin carnivore confrontation during thePleistocene, which is important to understand behavioralchanges during human evolution. In addition, the case of Neanderthals is analyzed in order to find evidence of past attacks using forensic observations. The results obtained posethat Neanderthals could potentially have been involved indangerous encounters during the Pleistocene, validating our methodology to approach past attacks from a forensic perspective.
Ursidae
Direct confrontation between humans and bears is relativelycommon in different parts of the world (Lathrop 2007) andmust be considered as either predatory or defensive (Herrero1985; Herrero and Fleck 1990). Subspecies involved in thesedangerous encounters are the black bear (
Ursus americanus
)(Murad and Boddy 1987), grizzly bear (
Ursus arctoshorribilis
) (Cardall and Rosen 2003; Kunimoto et al. 2004),Asian black bear (
Ursus thibetanus
) (Agarwal et al. 2011),and less commonly the polar bear (
Ursus maritimus
)(Herrero and Fleck 1990) and brown bear (
Ursus arctos
)(Ambarli and Bilgin 2008). Although other subspecies areinvolved in attacks on humans (Rajpurohit and Krausman2000; French 2001), only those cited here were studied inour forensic research. A total of 45 cases were analyzed.Ingeneral,deathisnotcommonafterabearattack(Herreroand Fleck 1990), although serious injuries are generated byteeth, claws, and paws (French 2001). The bear attack patternis one of the best studied in forensic medicine (e.g., Rasoolet al. 2010). Bears tend to rear up on their hind legs and strikevictims withtheirclaws(Dharetal.2008).Bitingthe victimisalso common, and a bear attack ends with different degrees of minor and major injuries, predominantly located in the upper halfofthebody(Dharetal.2008;Rasooletal.2010;Agarwalet al. 2011; Baliga et al. 2012), especially in the head and face(Thakur et al. 2007).The present observation of a total of 45 forensic cases iscommensurate with this known attack pattern of bears.Figure 2a shows that within the 38 case studies with bonemodifications, the main bone damage is located in the headzone(skullandmandible)andupperlimbs(clavicle,humerus,radius, ulna, metacarpals, and hand phalanges). Bears tend toattack the victim's head, causing wounds and fractures in that zone, and humans react by protecting themselves with their arms, causing damage in that region. Long bone diaphyseallinear, comminuted, and segmental fractures in the upper limbarenotrare,andfingeramputationisalsocommon(Dharetal.2008). All these bony injuries are frequently associated withgeneral softtissue wounds (Fig. 2b), as observed in other cases (Rasool et al. 2010). Therefore, bone modification after a bear attack would appear to occur in the body areas whereother general non bony wounds are inflicted by the animal.
Felidae
Feline attacks on humans reflect a predatory behavior in near ly all cases and follow the same pattern employed for preda-tion on other large mammals (Cohle et al. 1990) in both wildand captive contexts (e.g., Hejna 2010). These encountersmay not always be fatal for humans (Wright 1991), but dueto large cats attack pattern, they can result in very seriouswounds caused by teeth and claws. Feline-human conflictsthat end in dangerous encounters are increasingly commonoccurrences in different parts of the world (Nyhus andTilson 2004; Inskip and Zimmermann 2009).The felines (basically leopards (
Panthera pardus
) (Nabiet al. 2009a), jaguars (
Panthera onca
) (Neto etal. 2011), lions(
Panthera leo
) (Packer et al. 2005), tigers (
Panthera tigris
)(Langley and Hunter 2001), and cougars (
Puma concolor
))attack humans in the same way in most cases. They carryout a solitary surprise attack motivated by a predatory behav-ior that can be stimulated by the quick erratic movements of the victim (e.g., jogging or running) (Conrad 1992; Rollins
www.academia.edu/12436456/Large_carnivore_attacks_on_hominins_during_the_Pleistocene_A_forensic_approach_with_a_Neanderthal_example
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Post by Gorilla king on Dec 30, 2021 0:59:26 GMT -5
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Jiren
Black bear
“Water can flow, or it can crash”.
Posts: 319
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Post by Jiren on Jan 6, 2022 21:16:47 GMT -5
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Post by Gorilla king on Jan 13, 2022 10:07:18 GMT -5
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Post by Gorilla king on Jan 31, 2022 12:59:29 GMT -5
BEING PLANTIGRADE, ONE OF THE MOST IMPORTANT ADVANTAGES THAT URSIDS HAVE OVER FELIDS:books.google.com/books?id=8C4EAAAAQAAJ&pg=PA28&dq=the+bear,+a+plantigrade,+it+will+be+seen,+the+whole+of+the+bones+on+the+ground&hl=en&newbks=1&newbks_redir=0&source=gb_mobile_search&sa=X&ved=2ahUKEwjLv_bbx9z1AhVhRDABHeBnBjcQ6AF6BAgJEAM
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Post by Gorilla king on Feb 4, 2022 13:58:33 GMT -5
The evolution of skilled forelimb movements in carnivorans
Abstract
Emancipating the forelimbs from locomotion for use in other activities, such as food manipulation, is a major evolutionary milestone. A variety of selective forces and evolutionary correlates may influence the evolution of various degrees of skill with which the forelimbs are used. Using the order Carnivora as a test group, I assesed the relative influence of six factors: relative brain size, neocortical volume, manus proportions, body size, phylogenetic relatedness, type of locomotion and diet. I developed a rating system to describe the dexterity of individual species and compared the scores to the six factors using modern comparative methods. Only phylogeny and diet were significanly correlated with forelimb dexterity. More specifically, forelimb dexterity tends to be higher in caniform than in feliform carnivorans and decreases with increasing specialisation on vertebrate prey. I conclude that food handling and feeding niche breath have a significant effect upon the evolution of skilled forelimb movements. opus.uleth.ca/handle/10133/94?show=full
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Post by Gorilla king on Apr 11, 2022 16:04:12 GMT -5
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Post by Gorilla king on Jun 19, 2022 7:55:50 GMT -5
Forelimb Indicators of Prey-Size Preference in the Felidae
Abstract and Figures
The forelimbs, along with the crania, are an essential part of the prey-killing apparatus in cats. Linear morphometrics of the forelimbs were used to determine the morphological differences between felids that specialize on large prey, small prey, or mixed prey. We also compared the scaling of felid forelimbs to those of canids to test whether prey capture strategies affect forelimb scaling. Results suggest that large prey specialists have relatively robust forelimbs when compared with smaller prey specialists. This includes relatively more robust humeri and radii, relatively larger distal ends of the humerus, and relatively larger articular areas of the humerus and radius. Large prey specialists also had relatively longer olecranon processes of the ulna and wider proximal paws. These characters are all important for subduing large prey while the cat positions itself for the killing bite. Small prey specialists have relatively longer distal limb elements for swift prey capture, and mixed prey specialists had intermediate values with relatively more robust metacarpals. Arboreal felids also had more robust limbs. They had relatively longer proximal phalanges for better grip while climbing, and a relatively short brachial index (radius to humerus ratio). Additionally, we found that felids and canids differ in forelimb scaling, which emphasizes the dual use of forelimbs for locomotion and prey capture in felids. This morphometric technique worked well to separate prey-size preference in felids, but did not work as well to separate locomotor groups, as scansorial and terrestrial felids were not clearly distinguished.
Front Limb Segment Ratio (shorter frontlimbs are very useful for grappling with your opponent; lower score is better)
Humerus/Radius:
1. Jaguar - 81.9% 2. Tiger - 82.4% 3. Cougar - 82.7% 4. Leopard - 83.1% 5. Lion - 89.5%
(Smilodon Fatalis - 78.9%)
Humerus/MTC 3:
1. Jaguar - 32.8% 2. Tiger - 34.0% 3. Leopard/Lion - 34.9% 4. Cougar - 36.5%
(Smilodon Fatalis - 25.2%)
Humerus/Ulna (the precise value here is unknown; so I'll list them in their order):
1. Xenosmilus Hodsonae 2. Smilodon Fatalis 3. Jaguar 4. Tiger 5. Cougar 6. Lion 7. Leopard 8. Homotherium Serum 9. Homotherium Ischyros
Proximal Paw Width
In addition, large prey specialists have proportionally large proximal paw widths (PAW). The width of the proximal paws facilitates a stronger, more stable grip on large prey animals during the initial attack, as it would in gripping substrate (Watkins, 2003) or while climbing (Cartmill, 1985), and allows the force to be distributed more evenly across the entire paw.
1. Tiger – 79.95% 2. Jaguar – 79.81% 3. Lion – 79.73% 4. Snow Leopard – 78.46% 5. Clouded Leopard – 77.09% 6. Leopard – 73.01% 7. Cougar – 68.01%
(Smilodon Fatalis - 100%)
Brachial Index (lower value is better in this case)
With regards to brachial index (BI), Iwaniuk et al. (1999) and Gonyea (1976a) also found similar results. Arboreal felids have shorter radii relative to humeri, and therefore a smaller brachial index (BI) because shortened distal limbs increase the mechanical advantage of forelimb flexors and extensors, allowing arboreal species to climb more effectively. Shorter limbs also lower the center of gravity for arboreal cats favoring the ability to balance on high, narrow tree branches (Cartmill, 1985).
1. Clouded Leopard – 79.90% 2. Jaguar – 83.33% 3. Leopard – 84.87% 4. Cougar – 85.35% 5. Tiger – 85.56% 6. Snow Leopard – 89.01% 7. Lion – 91.13%
Humerus Robusticity Index
The results of this study suggest that large prey specialists have relatively robust forelimbs when compared with smaller prey specialists. Both the humerus (HRI) and radius (RRI) diaphyses were found to be consistently robust. This increased robusticity functions to protect against bending and torsion when under increased stress (Ruff and Hayes, 1983; Lanyon and Rubin, 1985), such as that encountered when grappling with large prey. The increased robustness in the humeri and radii of large prey specialists may also translate into a proportionally thicker cortical area of the humerus diaphysis, a possibility that will be explored in a future study.
1. Jaguar - 8.81% 2. Tiger - 8.53% 3. Lion - 8.44% 4. Snow Leopard - 8.15% 5. Leopard/Snow Leopard - 7.98% 6. Cougar - 7.64%
Humeral - Epicondylar Index
The humeral epicondylar index (HEI) was larger in large prey specialists. The humeral epicondyles serve as the origin for many muscles that stabilize the wrist during prey capture, such as: m. pronator teres, m. extensor carpi radialis, m. extensor carpi ulnaris, m. flexor carpi radialis, and m. flexor carpi ulnaris (Hebel and Stromberg, 1976; Schaller, 1992). The humeral epicondyles are also the point of origin of many of the digital flexor and extensor muscles that facilitate grasping of large prey during capture, such as: m. extensor digitorum communis, m. extensor digitorum lateralis, m. flexor digitorum superficialis, m. palmaris longus, and m. flexor digitorum profundus, in part (Hebel and Stromberg, 1976; Schaller, 1992). These larger epicondyles allow for larger originations and thereby larger muscles.
1. Tiger – 25.98% 2. Lion – 25.55% 3. Jaguar – 25.52% 4. Clouded Leopard – 24.11% 5. Snow Leopard – 24.10% 6. Leopard – 22.50% 7. Cougar – 21.57%
Olecranon Index
As found by Iwaniuk et al. (1999), the olecranon process of the ulna was relatively larger (OI) in large prey specialists. The triceps muscles insert on the olecranon process and are used primarily in arm extension. Increased size of these muscles would proffer a greater ability to push prey to the ground and hold them down while they position themselves for a killing bite.
1. Tiger – 22.47% 2. Snow Leopard – 21.19% 3. Lion – 20.78% 4. Jaguar – 19.92% 5. Leopard – 18.73% 6. Clouded Leopard – 18.07% 7. Cougar – 17.56%
(Smilodon Fatalis - 25%)
Radial Robusticity Index
This measures radius mediolateral diameter at midshaft divided by radius length. As mentioned above for humerus robusticity, a robust radius resists stresses on bones during fights and increases resistance to bites to the forelimb.
1. Jaguar - 10.16% 2. Clouded Leopard - 9.69% 3. Tiger - 9.45% 4. Lion - 9.15% 5. Cougar - 8.99% 6. Leopard - 8.89% 7. Snow Leopard - 8.82%
Manus Proportions
Small prey specialists also have elongated phalanges relative to metacarpals (MCP), which again shows distal elongation. Distal elongation likely provides a velocity advantage for catching small, elusive prey.
1. Clouded Leopard – 60.53% 2. Snow Leopard – 56.04% 3. Tiger – 48.91% 4. Jaguar – 47.36% 5. Lion – 39.01% 6. Cougar – 29.33% 7. Leopard – 27.19%
Radial Articular Area
In addition, large prey specialists differed significantly from both of the other groups in having relatively broader paws (PAW), and larger distal radial and metacarpal articular surface areas (RAI, RAA, and MC3RAA).
www.researchgate.net/publication/23720916_Forelimb_Indicators_of_Prey-Size_Preference_in_the_Felidae
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Post by Gorilla king on Jul 19, 2022 14:40:21 GMT -5
Comparative morphology of the scapular architecture in bears (Ursidae) as revealed by high resolution computed tomography
Among mammals, the family Ursidae comprises three basic locomotor behaviours: excellent swimming, slow to medium fast terrestrial locomotion and habitual tree-climbing. The detailed morphological basis of these complex behaviours still remains to be studied in many taxa. As a study object, we chose the scapula in bears, the general anatomical structure of which is known to differ from the scapulae of other carnivores. However, data on detailed scapular anatomy in different bear species is scarce. Therefore, we investigated potential correlations of the scapular structure with respective locomotor behaviour in Ursidae. In order to improve the knowledge on the morphology of bear scapulae, the authors conducted a comparative and high resolution computed tomographic study including the following species and subspecies: Eurasian brown bear (Ursus arctos arctos), Syrian brown bear (Ursus arctos syriacus), American black bear (Ursus americanus), polar bear (Ursus maritimus), spectacled bear (Tremarctos ornatus), and giant panda (Ailuropoda melanoleuca). For comparative purposes and in order to evaluate scapular adaptations related to arboreal activity, we also studied scapulae of red panda (Ailurus fulgens), and koala (Phascolarctos cinereus), a bear-like marsupial. This study revealed that all bear species conform in the following scapular features: (1) the scapula is rectangular in outline rather than fan shaped which is typical in other carnivores; (2) pronounced width of the scapular neck that exceeds the cranio-caudal diameter of the glenoid cavity by about one third; (3) extremely wide and very well represented supraspinatus and infraspinatus fossae; (4) a scapular spine that ends with a large, plate-like acromial process that projects ventrally towards the glenoid cavity further than in any other carnivore; (5) the caudal scapular border curves medially and caudally to delineate an additional fossa, the postscapular fossa (Fossa postscapularis). This fossa is well developed in all bears, regardless of body size. It distinguishes the bear scapula from that of all other carnivores. The present study also identified scapular features that were exclusively found in spectacled bear and giant panda, but not in the other bear species studied: (1) supraspinatus fossa is smaller than the infraspinatus fossa; (2) supraspinatus and infraspinatus fossae consist of very thin bone tissue (less than 1 mm); (3) scapular spine is slightly concave cranially while in the other bears it has a linear contour; (4) very small coracoid process. Perhaps not surprisingly, the same features were also found in the arboreal species studied for comparison, the red panda and koala, only to a greater extent. Considering these findings, we conclude that the identified skeletal specialised structures among Ursidae probably arose in the course of evolution of the species-specific locomotor behaviour despite of close phylogenetic affinity. Similar scapular features in Ursidae, in Ailuridae and in one marsupial (Phascolarctidae) might indicate functional convergence.
www.researchgate.net/publication/259744117_Comparative_morphology_of_the_scapular_architecture_in_bears_Ursidae_as_revealed_by_high_resolution_computed_tomography
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Post by Gorilla king on Jul 19, 2022 14:50:53 GMT -5
Reply #28:
For reference, scapula in a grizzly bear highlighted in blue:
Some important points from the study above:
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Post by arctozilla on Aug 2, 2022 3:53:31 GMT -5
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Post by oldindigosilverback on Aug 2, 2022 4:10:46 GMT -5
/\ There is a similar article which says an American lion’s bone structure is closer to that of a brown bear than that of a lion.
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Post by Gorilla king on Aug 7, 2022 3:57:50 GMT -5
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Post by arctozilla on Aug 8, 2022 7:58:02 GMT -5
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Post by arctozilla on Aug 29, 2022 7:09:38 GMT -5
Scapula Shape Index: It's scapula width/length ratio.Higher score indicates greater muscle attachement such asinfraspinatus supraspinatus and subscapuralis on the shoulder joint as well as greaterability to make certain movements like full-functional upper extremity movementincluding protraction,retraction,elevation,depression,upward rotation,and downward rotation all else being equal.[/u] P.Leo : 77% P.Tigris : 84% U.Arctos : 87% Edge : U.Arctos SAI: Surface area of lateral aspect of scapula relative to scapula length.Higher score Indicates greater relative size of muscles involved in the transfer of forces from the trunk to the forelimbs and in stabilizing the shoulder joint.[/u] P.Leo : 80% P.Tigris : 80% U.Arctos : 84% Edge : U.Arctos SMI: Deltopectoral crest length divided by humerus length. Higher score Displays greatermechanical advantage of deltoid and pectoral muscles at the shoulder joint.[/u] P.Leo : 62% P.Tigris : 62% U.Arctos : 72% Edge : U.Arctos API: Acromion process length/scapula length. Higher score in this ratio increases attachment forthe deltoid muscle.[/u] P.Leo : 8% P.Tigris : N/A U.Arctos: 19% Edge : U.Arctos HEI: The HEI index measures the relative size of wrist stabilizing muscles and well as severalgrasping muscles in area which facilitate prey grasping such as m. pronator teres, m.extensor carpi radialis, m. extensor carpi ulnaris, m. flexor carpi radialis, and m.flexorcarpi ulnaris ,m. extensor digitorum communis, m. extensor digitorum lateralis,m.flexor digitorum superficialis, m. palmarislongus,and m. flexor digitorum profundus.These muscles also likely help stability, pushing, and agility when legs are on ground.[/u] P.Leo : 26% P.Tigris : 27% U.Arctos : 30% Edge : U.Arctos OMA: Length of olecranon process relative to length of distal forelimb (Olecranon length/(Radiuslength+ Metacarpal length)). Higher score Indicates greater anatomical mechanicaladvantage of triceps brachii, an elbowextensor.[/u] P.Leo : 20% P.Tigris : 22% U.Arctos : 20% Edge : P.Tigris Overall edge : U.Arctos www.researchgate.net/publication/230843015_Postcranial_morphology_and_the_locomotor_habits_of_living_and_extinct_carnivoreswww.researchgate.net/publication/298056854_Sexual_selection_on_skeletal_shape_in_Carnivorawww.researchgate.net/publication/247494638_Ecomorphology_of_the_giant_short-faced_bears_Agriotherium_and_Arctoduswww.researchgate.net/publication/354365707_Anatomical_Features_of_Some_Bones_of_the_Forelimbs_of_Lions_Panthera_leowww.researchgate.net/publication/317543669_Morphological_and_Certain_Morphometrical_Study_of_Scapula_of_Indian_Tigerwww.researchgate.net/publication/280925355_Carnivoran_postcranial_adaptations_and_their_relationships_to_climateCredits to Yz
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Post by Gorilla king on Aug 29, 2022 13:48:43 GMT -5
Reply #34
Nice post. Yeah, as shown by all the studies posted in this thread, brown bears hold basically every single morphological advantage over felines.
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Post by Gorilla king on Nov 4, 2022 15:44:44 GMT -5
The American lion had much greater bending strength of the limbs, particularly of the humerus, than extant lions, being closer to those of the brown bear:"Claw and tooth marks left on a Pleistocene steppe bison mummy (Bison priscus; M. L. Guthrie, 1988; R. D. Guthrie, 1990) suggest that Panthera atrox adopted killing techniques similar to those used by modern lions. However, Anyonge (1996) has shown that the cross-sectional geometric properties (i.e. bending strength) of the limbs of Panthera atrox, particularly of the humerus, were much greater than those of the extant lion, being closer to those of the brown bear, Ursus arctos. In other words, the extinct lion had much stronger forelimbs than an extant lion of similar body size. Therefore, large prey could have been primarily subdued and restrained by the extremely powerful forelimbs of Panthera atrox, which would have greatly reduced stresses on the mandible during the canine bite."
www.researchgate.net/publication/231858147_Mandibular_force_profiles_of_extant_Carnivorans_and_implications_for_the_feeding_behaviours_of_extinct_predators
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Post by arctozilla on Nov 5, 2022 13:08:33 GMT -5
That's good. Cat fanatics gonna hate it.
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Post by Gorilla king on Jan 30, 2023 13:51:03 GMT -5
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Jiren
Black bear
“Water can flow, or it can crash”.
Posts: 319
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Post by Jiren on Jan 30, 2023 15:04:46 GMT -5
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