| Cane da Presa Meridionale, Il Cane Leone
Mauricio Lima
I am fascinated with the Cane Corz´/Cane ´e Presa dogs since I knew about the existence of this particular and unique type of dog. In fact, two years ago I contacted a kennel in Argentina and decided to bring a two month black female to my home (which almost causes me a divorce!!!). Since then, I have been studying and learning about this type of dogs and enjoying the company of my “cagna”. I must to say that several specific features of my dog call me the attention during this time, but in particular three attributes impress me a lot everyday, one is the pantherine-like movements she has, two is her highly predacious instinct (she is a formidable hunter of rabbits and rats, in fact yesterday she killed a quite big rat in my yard, which remind me a video of “India” from the CPM project!!) and finally her powerful bite. In fact, my friends visiting me at home get surprised by the feline movements of my “cagna”, and every time that I feed my dogs with bones I like to watch how she is able to deal with large bones compared with my adult boxer male, the difference is really impressive, she can process a big bone in less than 10 minutes while my boxer last almost an hour in processing a similar sized bone. The power of the bite is a general feature of every holding-grip dog breeds; in fact molossian breeds are characterized by its powerful bite. Nevertheless, the pantherine-like configuration of the body shape and movements of Cane Corz´/Cane ´e Presa dogs makes this breed unique and in my opinion the most interesting molossian dog. In fact, Flavio Bruno in his book “Il Cane Corso, studiato nella razza, nella storia, nella famiglia e nella società” proposed the idea that Roman Molossian dogs were mainly used for fighting against large felines, such as lions and tigers, and that Romans selected these dogs because its feline configuration and movements make them more successful to confront felines in the circus and the coliseum. We certainly know that domestic dogs are descendent of the gray wolf (Canis lupus), then, what the origin of these phenotypic traits in the Cane Corso dogs? Where come from its pantherine-like body configuration and the formidable power of its bite? I shall not give a definite answer to these questions, but I shall review some recent studies about carnivore and canine evolution in order to understand why Cane Corz´/Cane ´e Presa dogs exhibit these unique functional and structural features.
The extant order Carnivora includes 274 species in eleven families and spans a wider range of body sizes than any other mammalian order. Carnivores first appeared in the Paleocene, about 63 ma (millions of years ago) and diverged into two major branches, the Caniformia and Feliformia. The defining character of the order is the presence of carnassial teeth, a blade-like upper fourth premolar that occludes with a partially bladed lower first molar in a scissor-like action. The Caniformia includes the canids, ursids, mustelids, mephitids, procyonids, ailurids, amphicyonids (extinct beardogs), and aquatic carnivorans (pinnipeds), and the Feliformia includes the felids, hyaenids, herpestids, viverrids, percrocutids (extinct hyena-like forms), and nimravids (extinct cat-like forms).
Hyper-carnivores
Evolution has produced at least four different sorts of mammalian hyper-carnivores again and again, exemplified by two kinds of felids (sabertooth and conical canine teeth), large canids, and hyaenids. Hereafter these will be referred to as “cats’’ or catlike, wolf-like, and hyena-like, respectively. Although these forms all share features that unite them as hyper-carnivores, they also differ in significant ways that reflect differences in predatory style (slashing versus crushing killing bite), diet (bone consumption), and phylogeny. Based in the cranio-dental morphology Blaire Van Valkenburg (2007) establishes three very well defined categories in the hyper-carnivorous group, the cat-like, hyena-like and wolf-like eco-morphologies.
1) The cat-like eco-morphology represent a extreme in the eco-space of the hyper-carnivorous mammals, felines show the greatest reduction in the number of teeth compared with hyenas and canids, the post-carnassial molars and premolars are lost, the carnassial is large, developed as narrows bladelike tooth and the canines are large and very well developed. In synchrony with the reduction in the number of teeth, felines are characterized by a shorter rostrum compared with canids and hyenas, the net effect of this shortened rostrum is that a more powerful bite is achieved with the same muscles, that is because bringing the canines closer to the mandibular condyle increase the power of the bite for the same amount of muscular mass (Wang & Tedford 2008). Another important feature of feline skulls is the presence of an arched skull top caused by an inflated forehead area. This dome head may offer some advantages in its reinforcement of the bony structures that anchor the canine teeth (Wang & Tedford 2008). Other important anatomical and morphological features of felines are related with the neck structure, fore limb and body shape configuration. For example, Anton & Galobart (1999) showed the importance of the neck bones and musculature in mammalian predators, felines are characterized by a short, powerful neck musculature which a clear strong S curve, because the shorter muscles contract more efficiently than longer muscles, it is possible to exert more power with less effort.
2) The hyena-like eco-morphology is very well represented by the extant spotted hyena (Crocuta crocuta), an almost perfect bone-cracker carnivore. Hyenas are characterized by massive jaws, the reduction in the number of teeth are no so extreme as in felids, only molars are lost, as a consequence the premolars are extremely developed and located back in the mandible, together with massive carnassials hyenas can exert a formidable pressure in its bite. The rostrum of the hyenas is longer than felids, but because they have a reduced number of tooth, is shorter than most of the extant canid species. Also, hyena species show a domed head (no so marked as in felines) that can reinforce the bony structures that anchor the canine teeth and mandible muscles.
3) The wolf-like eco-morphology is very well represented by the wolf (Canis lupus), the dhole (Cuon alpinus) and the African wild dog (Lycaon pictus). In contrast to felines and hyenas the hyper-carnivore species of canids have been conservative in the tooth number, to accommodate a full set of teeth the rostrum is relatively long, the canines and incisors are located more forward. From this ancestral condition of a longer rostrum and a more flexible diet, the evolution of the most hyper-carnivorous lineages of canids tends to exhibit shorter and wider rostrum (Van Valkenburg & Koepfli 1993). Because the hyper-carnivorous canid species present today had evolved from hypo- and meso-carnivorous species they retain several of the ancestral features. Despite of this, wolves, dholes and African wild dogs showed shorter and more powerful necks than would be expected for their size compared with other members of canidae family (Wang & Tedford 2008). In particular, the dholes and African wild dogs have a shorter rostrum and wider muzzles than gray wolves. In fact, both wild dogs have a more powerful bite standardized by body mass than wolves (Wroe et al. 2005).
In sum the review of the craniodental eco-morphology of hyper-carnivorous mammals indicate the same general trend. Ecological specialization toward hyper-carnivore diet is associated morphologically with specific changes in the skull and dentition that include a relative lengthening of the shearing edges, reduction or loss of the post-carnassial dentition and the facial portion of the skull in order to improve the bite force and a domed head for reinforcing the bony structures that anchor the canine teeth (Van Valkenburgh & Ruff 1987; Radinsky 1981a, b; Biknevicius & Van Valkenburgh 1996). An extreme are cats with the most important reduction in the pre- and post molar dentition, hyenas conserve and enlarge the premolar dentition used in bone-cracking, and canids showed the more conservative structure conserving pre-and post-molar dentition and a longer rostrum. In sum, it is possible to assume that everything being equal, hyper-carnivorous forms tended to acquire a shorter rostrum in order to increase bite force.
Hunting strategies
The other fundamental feature of felids, which contrast with the wild dogs and hyenas, is the ability to grasp and subdue large preys with their forequarters. Large felids are able to capture and retain very large preys by the use of the forelimb, lions, leopards, tigers and jaguars have the ability to grapple and subdue prey by using their forequarters. The forelimbs of large felids are shorter, stronger and more robust than the canids or hyena forelimbs more adapted to pursuing the preys. The forequarters of recent canids and hyenas are specially adapted for running and for maximal stability during running and their ability to manipulate objects manually is limited (Hildebrand 1954; Andersson 2005). Hence, they adopt a different strategy, in which they engage in a pursuit that eventually exhausts the prey to the point where it can be brought down and killed with multiple bites. In consequence, the extant large canid predators have a restricted movement of the joints, long forelimbs for running fast and for longer time.
Roman molossian dogs (CC/CPM) are clearly characterized by a shorter rostrum, wider muzzle, stronger and shorter jaws than gray wolves and other domestic dogs. In fact the muzzle and the rostrum of Cane Corz´/Cane ´e Presa dogs are more similar to the African wild dog rostrum. In addition, the body shape, movements and fore limb structure remains more like a large cat than a dog, the shorter and more robust forelimbs and the larger hind legs (please see a picture of a CPM by side!!) enhance the explosive movement and the power of the Cane Corz´/Cane ´e Presa dogs, but also reduce their ability for running during long times as other canids species. What I want to stress here is that roman molossian dogs appears to be an example of a particular eco-morph of canids, although there are no extant species showing this morphology, a review of canid evolution can shed light about the origin of these morphological attributes.
Borophagines dogs
The subfamily Borophaginae is a terminal group of hyper-carnivores canids that developed strong bone-crushing dentitions. Because the specialized dentition for cracking bones, this group of species was known as the “hyaenoid dogs”, they were confined to the North American continent, appeared about 32 Ma and declined to extinction about 2 Ma (Xang & Tedford 2008). The first among the borophagines to develop strong jaws and shorter rostrum was the genus Aelurodon (from Greek ailurus (cat) and don (tooth)). The species of this genus weighed between 20 and 40 kg and they were quite similar in many aspects to African wild dogs, they share broad palates and multicuspid premolars. In addition this species showed a shorter and S-shaped neck very similar to the muscular and short necks showed by the large cats (lions, tigers and jaguars) (Xang & Tedford 2008). Other genus of this group was Epicyon (from Greek epi (near, before) and cyon (dog)), the species of this genus ranged between 30 and 75 kg., with a species Epicyon haydeni weighed more than 150 kg. Epicyon showed enlarged premolars, similar to hyenas that enabled them to deliver a powerful bite for cracking bones; this lineage was found across North America between 16 to 7 Ma. Derived from Epicyon, the genus Borophagus (from Greek boros (voracious), and Latin phago (eating)) was the last member of the family, they appeared about 12 Ma and become extinct just before the beginning of the Ice Age (1.8 Ma). The notion of a hyena-dog is closely related with this genus, Borophagus carried to the extreme the enlarged lower premolars, and it also had a strong jaw and a domed forehead that improved the jaw mechanism in order to sustain the tremendous force in the bite for cracking bones. These dogs weighed among 20 to 40 kg. Recent studies seem to indicate that the larger species of the borophagine dogs were characterized by several pantherine-like features, for example a shorter rostrum than the extant hyper-carnivores canids, in order to enhance bite force, also shorter, more flexible and more muscular forelimbs, and a remarkably shorter and S-shaped neck (Wang & Tedford 2008). All these features appear to make these dogs more capable to deal with large prey. In fact, Andersson (2004, 2005) determined that large species of borophagines have retained the ability to supinate their forearms. It is therefore likely that manual manipulation was part of their hunting behavior, by analogy with pantherine cats today (Andersson & Wederlin 2003).
The Dire wolf
About 0.5 Ma ago a very interesting species arose in North America, the dire wolf (Canis dirus), this was the larger species ever known of the genus Canis, it become extinct about 10.000 years ago and coexist with the gray wolf during several thousand of years. Dire wolves were very much like in appearance than the gray wolves; however they were characterized by a more developed and impressive dentition, larger carnassial and incisors, wider and shorter rostrum and shorter and stronger forelimbs than the gray wolf (Canis lupus). The morphological features of the dire wolf strongly suggest that this canid was a specialized hunter of mega-herbivore fauna and it become extinct as a consequence of the massive extinction of their preys.
A specialized wolf eco-morph
Data from extinct hyper-carnivore canid species clearly show that pantherine-like body size configuration and shorter and wider rostrum were features exhibited by these extinct canid species specialized as hyper-carnivorous and hunters of large preys. Nevertheless, an extinct eco-morph of the gray wolf (Canis lupus) appears to show some of the morphological features observed in the extinct borophaginae dogs. A recent study by Leonard et al. (2007) showed a previously unrecognized, uniquely adapted, and genetically distinct wolf eco-morph, which suffered extinction in the Late Pleistocene, along with other mega-fauna. These wolves showed unique and different morphological features than actual wolf populations, they tend to have short, broad palates with large carnassials, relative to their overall skull size, which suggest a kind of gray wolf adapted for producing relatively large bite forces (Leonard et al. 2007). These craniodental structures characteristic are found in bone crackers species, such as spotted hyenas (Crocuta crocuta) and Borophaginae canids that take prey larger than them. In all of these features, the eastern-Beringian wolves differed from the present day wolves suggesting a greater specialization for killing and consuming relatively large preys. This study revealed an evolutionary plasticity of craniodental form within C. lupus greater than previously observed in modern gray wolves. This wolf showed craniodental morphology more capable of capturing, dismembering, and consuming the bones of very large mega-herbivores.
This piece of evidence appears to reveal that there is an underlying phenotypic plasticity in the wolf genome able to explore different predator morphologies. For example, the greyhound breeds are a clear case of how the same species (Canis lupus familiaris) can show an extreme cursorial eco-morph characterized by the evolution of elongated limbs and feet in order to achieve higher speed during the pursuit of fast preys. The evolution of this hunting strategy is perfectly represented in felids such as, the African cheetah (Acinonix jubatus), but also in an American cheetah-like extinct cat (Miracinonyx trumani), and even in an extinct hyena (Chasmaporthetes). Despite that none of the extant canid species shows this extreme cursoriality in nature, the domestication of the wolf makes it possible and some phenotypic variants were used for speed hunting. A similar case is the molossian dogs, this kind of dogs appear to represent a particular eco-morph characterized by shorter rostrum and stronger bite force than wolves. In fact, the strongest bite forces in canids are exhibited by species showing a hyena-like craniodental structure such as, the African wild dog and the extinct dire wolf (Wroe et al. 2005). In addition, the pantherine-like movements of Cane Corz´/Cane ´e Presa dogs can be related with its shorter and stronger forelimbs and more rectangular body shape which make these dogs more explosive in its movements. It is possible to hypothesize that roman molossian dogs represent a particular morphological space of the gray wolf phenotypic plasticity. The bigger head, shorter rostrum and jaws, stronger and shorter muscled necks and fore limbs appears to correlate with an eco-morph “adapted” to hunt and consume large preys, crack bones and with a less cursorial hunting strategy than modern canids. Fossil borophaginae dogs, the dire wolf and an extinct eco-morph of the gray wolf share some of these phenotypic traits (in fact I suggest checking the photos of a mastino and a wolf skull in the zootecnia area of the Forum!!).
We can hypothesize that during the domestication of the gray wolf the ancestral genetic variation was transformed in many different ways leading to the process of breed formation. One of these paths resulted in a particular kind of dog, which seems to resemble some extinct lineages of wild dogs adapted to hunt and consume large preys. This unique molossian dog is able to move like a large cat and to exhibit a devastating powerful bite. Ancient Romans were so impressed by this kind of dog that used them as faithful companions of their legionaries. I think that the Cane Corz´/Cane ´e Presa is the most interesting molossian breed, not only because it’s unique morphological and functional structure but also based on the cultural and ecological background in which this breed was developed. The Cane Corz´/Cane ´e Presa dog is not only an ancient working breed developed in Italy, it seems to be a particular eco-morph not present in the extant wild canid species, with a clear functional meaning during its history. I am still wondering how Cane Corz´/Cane ´e Presa dogs can be used in the modern human society and how to preserve the essence of this breed. Nevertheless, I just only may say that every time I look my “cagna” to move like a big cat chasing rabbits, I enjoy imaging that some of the ancestral genetic legacy of those extinct large wild dogs is still present in this wonderful type of dog.
Bibliography
Andersson, K. 2004. Elbow joint morphology as a guide to forearm function and foraging behaviour in mammalian carnivores. Zoological Journal of the Linnean Society 142:91-104.
Andersson, K. (2005) Were there pack-hunting canids in the Tertiary, and how can we know? Paleobiology 31: 56-72.
Andersson, K., & Werdelin, L. (2003) The evolution of cursorial carnivores in the Tertiary: implications of elbow-joint morphology. Proceedings of the Royal Society of London B 270: S163-S165.
Anton, M. & Galobart, A. (1999) Neck function and predatory behaviour in the scimitar tooth cat Homoherium latidens (Owen). Journal of Vertebrate Paleontology 19:771-784.
Biknevicius, A. & Van Valkenburgh, B. (1996) Design for killing: craniodental adaptations of predators. In: Gittleman, J. L., editor. Carnivore behavior, ecology, and evolution. Vol. II, Ithaca: Cornell University Press. Pp 393–428.
Hildebrand, M. (1954) Comparative morphology of the body skeleton in the recent Canidae. University of California Publications in Zoology 52:399-470.
Leonard, J. A., Vilá, C., Fox-Dobbs, K., Koch, P. L., Wayne, R. K. & Van Valkenburg, B. (2007) Megafaunal extinctions and the disappearance of a specialized wolf ecomorph. Current Biology 17:1146–1150.
Van Valkenburg, B. (2007) Déja`vu: the evolution of feeding morphologies in the Carnivora. Integrative and Comparative Biology, pp. 1–17. doi:10.1093/icb/icm016
Van Valkenburgh B, Ruff, C. B. (1987) Canine tooth strength and killing behavior in large carnivores. Journal of Zoology 212:379–97.
Van Valkenburgh, B. & Koepfli, K. (1993) Cranial and dental adaptations for predation in canids. In: Dunstone, N. & Gorman, M. L. editors. Mammals as predators. Oxford: Oxford University Press. Pp. 15–37.
Radinsky, L. B. (1981a) Evolution of skull shape in carnivores. 1. Representative modern carnivores. Biological Journal of the Linnean Society 15:369-388.
Radinsky, L. B. (1981b) Evolution of skull shape in carnivores. 2. Additional modern carnivores. Biological Journal of the Linnean Society 16:337-355.
Wang, X. & Tedford, R. H. (2008) Dogs: their fossil relatives and evolutionary history. Columbia University Press, New York.
Wroe, S., McHenry, C. & Thomason, J. (2005) Bite club: comparative bite force in big biting mammals and the prediction of predatory behavior in fossil taxa. Proceddings of the Royal Society of London B 272: 619-625
NB: This is a version of “Cane Corso, Il Cane Leone” wrote as a contribution for the Contado del Molise
Mauricio Lima
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