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Cheetah Dew Claws and Big Cat Killing Techniques
#1
Reddhole Wrote:Short communications
Edited by M. L. Gorman
J. Zool., Lond. (2000) 251, 535±537 #2000 The Zoological Society of London
The cheetah (Acinonyx jubatus) dewclaw: specialization overlooked
Tiziano Londei
Dipartimento di Biologia, UniversitaÁ degli Studi, Via Celoria 26, 20133 Milan, Italy
INTRODUCTION
The cheetah Acinonyx jubatus is an atypical felid, well
known for having blunt, only slightly curved, and only
partly retractile claws, clearly an adaptation for highspeed
locomotion in the pursuit of swift mammals.
However, saying that prey `is usually knocked down by
the force of the cheetah's charge' (Nowak, 1999) is
incorrect, because this predator actually relies on the
claw of the first digit of the forepaw, the so-called
dewclaw, to hook the fleeing prey off balance. Although
(1) this was understood by Indian huntsmen through
their use of tame cheetahs and published (Burton, 1950)
in a natural history journal circulating well outside
India, (2) wounds attributable to the dewclaws of
cheetahs were later observed (Schaller, 1972) on prey
animals in Africa, the area of most research on this
felid, and (3) the information from India was finally
reported (though with the wrong year in the citation) in
an authoritative book on African mammals (Kingdon,
1977), no systematic study of the dewclaw itself, or of
explicitly related questions, has been made. Perhaps the
general connotation of the term `dewclaw', as intended
for a non-functional claw on a rudimentary digit as in
the case of dogs, has masked the importance of what is
not only a strongly curved and sharply pointed, but also
a very large claw in the cheetah. In fact, this specialization
of the cheetah has escaped the attention of
behaviourists (Eaton, 1970), anatomists (Gonyea &
Ashworth, 1975), and palaeontologists (Adams, 1979).

METHODS
The present investigation developed along 2 lines.
(1) Frame-by-frame analysis of filmed sequences of the
predatory behaviour of large felids, videotaped from
television. This involved 3 instances of tiger Panthera
tigris preying on sambar Cervus unicolor, spotted deer
Axis axis and Hanuman langur Semnopithecus entellus;
4 instances of lion Panthera leo preying on Burchell's
zebra Equus burchelli and the blue wildebeest Connochaetes
taurinus; 2 instances of leopard Panthera pardus
preying on Thompson's gazelle Gazella thompsonii and
hare Lepus sp.; 1 instance of puma Felis concolor
preying on the wapiti Cervus canadensis; 9 instances of
cheetah preying on the blue wildebeest, the topi Damaliscus
lunatus, gazelle Gazella granti and G. thompsonii,
and hare.
(2) Measurement of the dewclaw and, for comparison,
the claw of the second digit of the forepaw in museum
specimens, pelts or skeletons. 

RESULTS
The predatory sequences showed that tigers, lions and
leopards all relied on a strong impact to strike the prey
to the ground, though depending on the prey's size the
action varied from a blow with one forepaw to the
collision of the predator's entire body. All the claws of
the forepaws and, in the case of large prey, even of the
hindpaws too, were used by the predator as hooking
tools to progress with the mouth towards the prey's
neck, this being reached very quickly, often before the
prey fell down. In the one sequence with a puma the
predator's jaws seemed less important initially (for prey
grasping), but the body impact seemed even stronger, as
the puma leaped to the forequarters of the still deer
after an accelerative dash and struck it with both
forearms while taking full grasp with the forepaws. On
the contrary, the relative speed of the cheetahs to their
fleeing victims was always low, which made the impact
rather weak.
All the nine sequences showed that only
when the prey was on its back had the cheetah's jaws a
main role, the well-known strangling action. Although
four inexperienced cheetahs bit a standing wildebeest in
various parts of the body during conjunct attacks, the
prey escaped eventually. Also with small prey (hare) a
cheetah seemed more reluctant than a leopard to use the
mouth, initially. Irrespective of the prey's size the
cheetah forced it down through a hampering action,
trying to anchor one forelimb or both to the prey's
body. Cheetahs `hanging' on large animals (wildebeest)
clearly showed dewclaws being their only hooking tools.
The analysis of dewclaw relative size (Table 1) met, in
part, the behavioural observation. In the tiger, lion and
leopard, the dewclaw is only slightly larger than the
claw of the second digit, which matches the joint action
of these (and the other) forepaw claws in predation. The
cheetah clearly shows an enlarged dewclaw, as expected
from the separate role of this claw.
The intermediate
size of the dewclaw of the puma is an unexpected result,
however.
DISCUSSION
Both the behavioural and the morphological analyses
confirm the special role of the dewclaw in the cheetah: a
strong hook to stop running animals by using the
energy of the victim itself.
However, this would hardly
be an explanation for the rather large dewclaw in the
puma. The one behavioural sequence analysed in this
study is in line with the habit of the puma making
short-distance, surprise attacks (Nowak, 1999). For the
massive action of limbs to strike the prey this felid seems
closer to representatives of the genus Panthera, these
showing no special size or use of their dewclaws.
When the novel idea of a close relationship between
the cheetah and puma was proposed, their dewclaws
were not taken into consideration: Adam's (1979) statement
that the Old World cheetah lineage had the limbs
specialized as `strictly propulsive structures', is inaccurate
because of the predatory dewclaw of the extant
cheetah. The present finding of the puma as an intermediate
between the cheetah and other large felids
for dewclaw size, supports the idea (van Valkenburgh,
Grady & KurteÂn, 1990) that, despite some later reversal
to a more primitive, typically feline structure, the puma
originated from felids like the fossil cheetah-like cat
Miracinonyx inexpectatus of North America, which had
longer, more cursorial limbs (though maintaining fully
retractile claws) and, as far as one can judge from
phalanx size, larger dewclaws than the extant puma.
Therefore, although a more behavioural study may
suggest some special adaptation of the puma's
dewclaw, its rather large size may be a leftover
character, instead.
Although the dewclaw seems to have an important
role in the predatory function of the forepaw in all
felids, and thus it is properly not a `dewclaw', in the
cheetah it seems to have taken on the predatory
function of the entire forepaw, as the other claws lost
this function because of locomotory adaptation.
A
special study of fossil felids with robust first digits, as
well as of extant felids with large dewclaws, would help
to understand the progress towards cheetah dewclaw
specialization, which has perhaps occurred with less
extreme outcomes along other lines of felid evolution.

________________________________________________________________________________________

taipan Wrote:Good topic Reddhole!

Here's some further information - including cheetahs & their important dew (hunting) claw.

Unlike other large predators such as the wolf or the spotted hyena, which essentially kill
their prey by pulling it down and eating it while still alive, cats in general tend to dispatch their
chosen victims first, before they start to consume it. In cats, large claws and powerfully
developed anterior limbs are ideally suited to catch prey and retaining a hold while wrestling
it into a position where the canines may be employed in a bite (TURNER & ANTÓN, 1996).
Canids lack retractile claws and their canines are less developed, so that sheer weight of
numbers is often the most important element in bringing down prey.
The precise hunting technique, which includes the method of capture and dispatch,
depends on the size of the cat, its overall morphology and the size and type of prey.
Moreover, the mode of hunting also depends upon the social structures observed in various
felids, meaning if they hunt in prides or rather solitary.
It is generally noticed that especially in cats, a strong interaction of innate and learned
patterns of behavior is of great importance. Cats develop an early interest in chasing
anything that moves, and will go through an elaborate sequence of crouching, wriggling the
hind-quarters, and pouncing (TURNER & ANTÓN, 1996). However, what they seem less
secure about is what to do with the object once they have seized it, although the neck region
appears to be sought instinctively. Female cats have been observed of bringing live prey for
their kittens to practice capture and killing. In addition, at a certain age the young offspring
will join their mother in hunting, this way they get to learn what prey to take and how it is
supposed to be killed.
For modern pantherine cats, smaller prey is killed by a bite at the rear of the neck, thereby
the upper canines drive between the vertebrae and severe the spinal cord (LEYHAUSEN,
1965; SCHALLER, 1967 & 1972; GONYEA, 1976). Larger animals like ungulates require
different approaches. They developed posteriorly directed horns along with an increase in
length of the cervical spines, which possibly evolved, in part, for protection against predators.
Prey animal of large size are rarely knocked over by the impact of the predators body;
instead during the pounce, the hind feet of the felid usually do not leave the ground. The
prey is seized and the predator pulls the prey towards itself. In this manner, as the victim is
pulled down, the predator is able to maintain contact with the prey, and in doing so controls
the victim’s movements (LEYHAUSEN 1965b; SCHALLER, 1967 & 1972; KLEIMANN &
EISENBERG, 1973).

[Image: cathunting1.jpg]

Prey is usually grabbed by the throat or the muzzle with a strong bite, at which it is aided by
its long retractile claws and powerful front legs (see Figure 7.1 and 7.2). Death results
mostly from suffocation rather than a violent and bloody end (TURNER & ANTÓN, 1996). This
technique may be used to avoid the pointed horns that protect the nape of the neck in many
ungulate prey species (GONYEA, 1976).

[Image: cathunting2.jpg]

The cheetah on the other hand is forced to employ a different hunting method, because its
claws can’t be used as a grasping device, and its body proportions are that of a sprinter, lean
and long. However, like many of the other cats it is perfectly adept at the stalk to bring itself
closer to its prey. The final rush takes the form of a high speed chase, often over several
hundred meters, during which the twists and turns of the usually small prey are relentlessly
followed. The capture is achieved at high speed, normally not by a leap onto the back of the
animal but by clawing at one side of the rear of the prey and pulling backward in a complex
and carefully coordinated maneuver. This causes the prey to lose balance and collapse, and
usually results in its tumbling over. The large dewclaw on the inside of the cheetah’s front
paw is employed in this technique, in effect “hooking” the back leg of the unfortunate animal.

Finally, it will be seized by the throat and strangled (NOWAK, 1991).

[Image: cathunting3.jpg]

Source - KILLING BEHAVIOR IN SMILODON FATALIS (MAMMALIA, CARNIVORA, FELIDAE) BASED ON FUNCTIONAL ANATOMY AND BODY PROPORTIONS OF THE FRONT- AND HIND LIMBS - JENS-UWE SCHMIEDER, JULY 2000.
[Image: wildcat10-CougarHuntingDeer.jpg]
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