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By Dan Famini (UC-Davis), with help from John R. Hutchinson (was at Stanford; now at RVC)
(copyright D. Famini and J.R. Hutchinson, 2003)
[This essay is intended for educational use, not as a scientific publication, and we ask that contents of this paper are only used in other venues with our permission]
Elephant "Bun Term" with mahout from Pattaya elephant camp during one of our experiments. Photo: Richard Lair
As the largest extant animal on land, there is a mystique about elephants that makes them an obvious and interesting topic of study. Unfortunately the locomotion of elephants is poorly understood, even basic parameters such as maximum velocity (Table 1). This is largely because finding active elephants and accurately measuring their speeds is a difficult, and potentially dangerous, undertaking. Many accessible elephants of captivity are sedentary compared to their wild counterparts, and seem incapable of providing information on the species' peak locomotor performance. On the other hand, the conditions and the elephants found in the field are inhospitable towards accurate and reliable measurement techniques. Consequently, the majority of data pertaining to elephant locomotion, particularly maximum velocity, comes not from scientific information, but from the educated guesses of individuals with elephant experience. Anecdotes are subjective, and anecdotes regarding elephants are particularly prone to overestimation due to the impressive stature of the animals. Inaccuracy in both estimating elephant speeds and in referencing the estimates of earlier authors has created an inflated and confused idea of the speed of elephants. What gait(s) elephants use at their fastest speeds (and in some cases any speed) also is a subject of much confusion in the popular and scientific literature. We review the history of these speed estimates and gait descriptions briefly here in order to clarify this muddled history of study. Hutchinson et al. (2003,2006) provide a modern assessment of both speed and gait in Asian and African elephants.
The earliest known study of elephant locomotion was conducted by Eadweard Muybridge (1899) who captured several trials of an Asian Elephant using high speed photography. Muybridge tried to obtain "as fast a speed as vigorous persuasion could induce -- equivalent to a mile in somewhat less than seven minutes (3.4 m/s)." Later analysis of these same images estimated the fastest photographed trial at 3.8 m/s [[1]] (Alexander 1979). Muybridge made no claim to have captured an elephant's top performance, and for the maximum possible velocity Muybridge quotes an estimate by Sir Samuel Baker (1890). Sir Baker had written a two volume memoir of big game hunts around the world. Within these narratives, Baker comments that the "African elephant is capable of a speed of 15 miles an hour (6.7 m/s), which it could keep up for 200-300 yards, after which it would travel at about 10 miles per hour (4.5 m/s)."
A significantly faster estimate of 24.5 mph (11.2 m/s) comes from a 1937 article in Natural History by Roy Chapman Andrews. The article's focus is actually about the speed of deer bot flies, Cephanemyia pratti, which Andrews claims can reach a velocity of 818 mph. That preposterous statement has since been proven to be erroneous (May 1999). Within Andrews' article there is a large chart containing the maximum speeds of many animals, people, and vehicles. A large variety of methods are used, predominantly automobile speedometers, but no method is ascribed to the estimate for elephants. The only details Andrews gives are that the elephant was charging over a length of 120 yards. Howell (1944) claims that Andrews' estimate is "based on the experience of one of the staff." Andrews was the Director of the of Natural History at the time, so it is entirely plausible that his information came from one of his employees, or that Howell was simply referring to Andrews himself. Andrews also mentions that "Dr. William K. Gregory, of the of Natural History, has revealed an interesting relationship between anatomy and speed." Gregory did publish a related article (1912) but it is written from an evolutionary context, with reports on sizes and ratios of the muscles and bones of many animals. It contains no speed estimates for elephants. The 11.2 m/s "estimate" from Andrews' chart, without any substantiation, became the standard elephant speed estimate for at least forty years.
One of the most widely cited sources for the maximum velocity of elephants is Howell's book, Speed in Animal's (1944). Howell quotes both Andrews' estimate of 11.2 m/s over 120 yards and Muybridge (1877) for 6.7 m/s over 200-300 yards (which is actually Baker's estimate). These numbers were portrayed as the best available estimates, yet Howell recognizes that "There are no authentic figures on the maximum speed of an elephant" (p. 52). Many authors of books about elephants or animals in general (and not locomotion specifically) refer to these values. Breeland (1948) states that "one African elephant has been timed with a stop watch at 24 mph for 120 yards." Breeland mentions both Howell's book and the journal Natural History in his selected references, but it is unclear where he got the information regarding this timed trial. Andrews had noted all of the times measured by watches, but the elephant's time was not one of them. Bourliere (1964) quotes the 11.2 m/s as from Howell, without any disclaimer. A rounded form of the 11.2 m/s estimate appears in Beebe (1968), Van Gelder (1969), Borst (1969), and (1977). All four of these works are about animals or elephants in general, and none offer any further explanation or source for the maximum velocity estimate.
The 7 and 11 m/s estimates are not called into question until a journal article about high-speed buffalo and elephant locomotion by Alexander (1979). He points out that "it seems likely that the casual observers who have seen elephants charging will be liable to exaggerate their speeds." There is no mention of Andrews or Baker, and the numbers are presented as estimates that "Howell reports". However, Alexander (1979) does measure an elephant's speed from video analysis at 4-4.5 m/s; the first credible estimate since Muybridge (1899). Garland (1983) also expressed doubts about the existing estimate of 40 km/h (~11.2 m/s). He alludes that "W.P.Coombs (pers. comm.) doubts the credibility of the higher figure so I have used 35 km/h (9.7 m/s)." However, provides no rationale or support for why he chose to particular value. Christiansen (2002) went so far as to exclude elephants from his scaling study of mammal maximum speed and limb proportions, "owing to their apomorphic appendicular anatomy and mode of locomotion." (p.687). This was a view also held by Paul (1998), who claimed that "Because elephants are unable to run, and must always walk with at least one foot contacting the ground, they should not be able to exceed ~20 km/h. A racing large Asian elephant bull (in a video) won with a peak speed of 19 km/h" (p.259). Paul also asserted that elephant-sized extinct animals, including dinosaurs, refuted the popular notion that large animals cannot be fast, suggesting that elephants were not reliable indicators of the size limits on speed and gait. In contradiction, in another speed-scaling study Iriarte-Díaz (2002) argued that larger animals were very limited in their range of locomotor performance. The latter study entered speed data of 9.45 and 7.02 m/s for African and Asian elephants respectively, citing two mammalogy texts and (1983) as sources. Have anecdotes surreptitiously become data? Are they trustworthy? An analogy could be made that allowing sloppy speed estimates into a biomechanics study is akin to a morphometrics study measuring a bone's length from across a museum hall with a ruler. Standards for these data should be carefully considered by authors and reviewers.
Doubts regarding older anecdotal quotes have only caused greater confusion and the replacement of old anecdotal information with new anecdotes. In the last decade sources not specifically about locomotion have reported a variety of maximum velocities for African elephants. Jackson (1990) and Groning (2000) reported 25 km/hr (6.9 m/s). Estes (1991) and Spinage (1994) reported 30 km/hr (8.3 m/s). Le Rue III (1994) quotes 40 km/hr (11.2m/s), but remarkably the number did not descend from Andrews (1937) but rather from a Dr. Griznemek who reportedly clocked the value with a Land Rover speedometer. One of the newest books on elephants contains the most extreme claim yet as S. Alexander (2000) states that "a mature African bull can achieve speeds 30 mph (13.3 m/s)." While S. Alexander refers to Ivan T. Sanderson for quotes on the velocity of Asian elephants (max of 15 mph (6.67 m/s)), there is no reference offered for the velocity of African elephants. As might be expected, the greater overestimates are being found in less scientific sources. However, these exaggerations also reflect the lack of consensus within the expert community, and most importantly the dearth of scientific studies on the subject.
Evaluating the way in which elephants move is far more difficult than measuring speed. In addition to the limited access to elephants, the complexity of quadrupedal movement is a challenge to measure, understand, or describe. There are few scientific reports on elephant locomotion, and none have fully quantified and described the kinematic and kinetic variables that define gaits. The lack of accurate and detailed information has been compounded by ambiguous and conflicting gait terminology. Consequently, a wide variety of gaits have been attributed to elephants. These include the walk, running walk, run, shuffling run, shuffling trot, shuffle, amble, ambling walk, rack, and pace. In addition there is a lack of consistency as to what the different gait names mean. Even with this many terms for elephant gaits, the same word often has different meanings depending on the author.
Muybridge (1899) is the oldest known source on the classification of quadrupedal gaits in general, including elephant gaits. He states that elephants only "walk" and "amble" (p. 67 of 1957 edition). Muybridge defines gaits in terms of footfall pattern and number of limbs supporting the animal at different times throughout a stride. In both the walk and amble each foot moves sequentially with the hindfoot moving before the forefoot on each side. The number of supporting limbs alternates between 2 and 3 in the walk, and between 1 and 2 in the amble. Muybridge states that "Practically, [the amble] is an accelerated walk." Muybridge claims that one of his photo sequences (plate #27) of an Asian elephant walking is an amble, but it appears to actually have at least 2 limbs of support at all times.
Howell (1944) substitutes the term "running walk" for Muybridge's "amble". In addition, Howell differentiates between "slow" movements and their quicker counterparts. Throughout a stride, a "slow walk" has 4, 3 or 2 limbs supporting the animal at different instances. A "fast walk" has either 3 or 2 supporting limbs. A "slow running walk" has 3, 2 or 1 supporting limbs, and a "fast running walk" has 2 or 1 supporting limbs. In apparent contradiction, Howell states that elephants rely "exclusively upon the walk or its more speedy equivalent, the running walk, which permits it to keep at least two feet always upon the ground" (p.52). Howell views the sequence of footfalls with the left foot first, calling the Left Front, Right Hind, Right Front, Left Hind sequence used by elephants a "diagonal walk" (p.228). Further, he explains that, "The running walk comes natural to very few animals. In diagonal sequence, it is the exclusive speed gait of the elephant" (p. 232).
Bourliere (1964) returns to Muybridge's term of "amble" claiming it as "the chief manner of rapid locomotion" for Proboscidea (p.4). However, Bourliere states that "in the slow amble, the body is alternately supported by two or three diagonal or lateral legs, but the swifter the animal moves, the more the diagonal pattern is replaced by a lateral one" (p.4). This deviates in both limb support and footfall sequence from the Muybridge's definition of "amble". Alexander (2000) also describes what appears to be a Muybridge "amble". On page 52 he simply states that elephants can "only walk or amble, keeping at least one foot always on the ground."
The term "amble" has also been used to describe a completely different gait, in which both limbs on the same side move synchronously. This gait is used commonly by giraffes and camels, and Muybridge called this gait the "rack" or "pace". In fact, Howell chooses to use the term "running walk" for an accelerated "walk" at least in part to avoid confusion as the term amble is "sometimes used to designate the pace" (p.231). Van Gelder (1969) states that "Elephants, giraffes, camels, hyenas, and some young dogs move both legs on the same side at the same time in a gait called pacing, or ambling" (p.35).
Beebe (1968) claims that elephants cannot run because "elephant legs do not have the spring necessary for running." Eltringham (1982) also states that elephants cannot run, but because "in the accepted sense since it must keep one foot on the ground at all times." Even so, he uses the words "shuffling run" to describe fast elephant movement. According to Eltringham, the shuffling run is distinct from "a fast extended walk during which it takes maximum strides." Similarly, Spinage (1994) reports that "the elephant can neither jump, trot, canter, or gallop" and "movement is restricted to a walk" (p.46). However, he a calls the elephants fastest movement a "shuffling trot" (p. 43). To avoid self-contradiction Spinage must consider the "trot" and "shuffling trot" different types of movement, yet he offers no definitions or means to discern the two gaits. Gale (1974) also concurs that elephants "cannot leap, trot, gallop, or canter", calling the elephant gait a "shuffle."
Gambaryan (1974) uses the term "fast walk" that would seem to be synonymous with Howell's running walk. However, Gambaryan's observations about the footfall pattern are actually more along the lines of Bourliere's. He describes that "a change in the rhythm of locomotion toward a rack is characteristic for elephants during slow movement, while a reverse switch of rhythm is typical during accelerated motion" (p. 167). Gambaryan goes on to knowingly (but inappropriately) use "running". According to his own definition, "running is a form of high-speed motion with a stage of flight in the air. This does not apply to elephants, but still we think it is worthwhile calling the fastest form of this animal's locomotion running" (p. 168).
In a paper on fast locomotion, Alexander (1979) also uses the term running to describe elephant locomotion. Alexander (1982) describes eight different quadrupedal running gaits. He clarifies that in bipeds, running differs from walking in that when running the leg acts as a spring with the hip reaching its lowest point during mid-stance. In contrast, in walking the hip reaches its highest point at mid-stance. It is implied that these distinctions hold for quadrupeds. Alexander explains that the "amble is the unusual running gait of elephants." In Alexander's "amble", the limbs have relative phase relationships "the same as for a typical quadrupedal walk" of 0.0, 0.25, 0.5, 0.75 with forelimbs following hind on the same side, as per Muybridge. He does not state what other gaits an elephant may be capable of, just that "Elephants generally use the amble instead of the trot and have no faster gait" (p.100). Estes (1991) uses the term "ambling walk" to define elephants' only gait, but since he offers no definition it is unclear if this is synonymous with other authors' amble or walk. In general, "amble" has become a sloppily applied and vague term that might best be abandoned in gait analysis.
Hildebrand (1985) uses limb phase relationships to distinguish different quadrupedal running gaits. Like Alexander's term "duty factor", Hildebrand also distinguishes running from walking based on whether the foot is in contact with the ground for more than or less than half of the stride. However, Hildebrand has his own term called the "singlefoot" for gaits in which "consecutive foot falls of the four feet are about equally spaced in time" (p. 40). Hildebrand distinguishes between diagonal and lateral sequences, but his definitions for the terms are the opposite of Howell's. Hildebrand's gait terminology consists of all three descriptors: walking/running, gait and order of sequence (lateral vs. diagonal). Thus, according to Hildebrand, "the running singlefoot in lateral sequence is a smooth gait used by elephants" (p.40).
Another term, charging, while not a scientifically recognized phrase, has a significant impact on how elephant information has been presented. It is no coincidence that all of the fastest velocity overestimates all mention that the maximum velocity is of a "charging" elephant (Baker, Andrews, Le Rue III, etc.). The phrase "charging" is not used or defined in any of the texts exploring animal locomotion. Where the phrase has been employed it appears to be used as if it were an explanation for an otherwise illogically fast speed.
A superb example of the power of anecdotal misinformation comes from Sir J. E. Tennet's 1867 book The Wild Elephant. On page 41 Tennet makes the assertion that "I am disposed to think that the elephant is too weighty and unwieldy to leap" and that the elephant cannot "gallop", but rather "shuffles." The reason for Tennet's lack of conviction regarding his idea that elephants cannot jump is an account in the 1866 Colombo Observer claiming that an angered bull elephant "fairly leaped the barrier, of some fifteen feet in high, only carrying away the top cross beam with a great crash." Tennet was skeptical of the claim, and questioned the accuracy of the report. In the book's preface is a letter from the office of the Observer who did some further investigation, reporting that "the result is the usual one whenever exact measurements are substituted for guess-work." The barrier the elephant scaled had not been a full 15 feet, but 12 feet in full, and only 9 below the top bar. In addition there was a 2.5 foot mound behind the fence, meaning the elephant only had to scale a meager 6.5 feet. Elephants, particularly a full-grown "Tusker", are quite capable of having limbs over 6 feet in length, rendering a 6.5 foot barrier little barrier at all. Tennet's correct conclusion that elephants could not leap had been undermined by unreliable observational misinformation. Tennet's situation was not unique. For as long as elephant locomotion has been studied there have been over-estimations of elephant's abilities. While modern technology has replaced visual guesses with guesses from Land Rover speedometers today, we are still hindered by "guess-work" and in a severe shortage of "exact measurements."
The understanding of elephant locomotion has been doubly stymied. First, there is the inaccessibility of the animals themselves, which has led to more anecdotal guesses and the spread of misinformation. Second, the lack of a consistent language to describe the movements of elephants has hindered the spread of what knowledge does exist. The purpose of our studies (Hutchinson et al., 2003,2006) were to accurately quantify and describe the basic kinematics of elephants and inspect whether they showed signs of a gait transition. Future work is needed to test whether they truly run, why their speed and gait are limited, and how their unusual locomotion evolved, but some clarity regarding the speed and gait of fast elephants is emerging at last.
Andrews, R.C. (1937) Wings Win. Natural History, (October 1937) v. 40 p. 559-65.
Alexander, R. McN. (1979) Mechanical stresses in fast locomotion of buffalo (Syncerus caffer) and elephant (Loxodonta africana). Journal of Zoological Society of London, (1979) v. 189 p. 135-44.
Alexander R. McN. (1982) Locomotion of Animals. Blackie & Son Ltd., Glascow UK.
Alexander, S (2000) The Astonishing Elephant. Random House, New York.
Baker, S.W. Sir. (1890) Wild Beasts and Their Ways. 2 volumes. Macmillan, New York.
Beebe, B.F. (1968) African Elephants. David McKay Co, Inc., New York.
Borst, J. (1969) A Field Guide to The Larger Mammals of Africa. Houghton Milon Co., Boston.
Bourliere, F. (1964) The Natural History of Animals, 3rd ed. Alfred E Knopf., New York.
Breeland, O.P. (1948) Animal Facts and Fallacies. Harper & Bros., New York.
Christiansen, P. (2002) Locomotion in terrestrial mammals: the influence of body mass, limb length and bone proportions on speed. Zoological Journal of the Linnaean Society (2002) v. 136 p. 685-714.
Eltringham, S.K. (1982) Elephants. Blandford Press, Poole Dorset, UK.
Estes, R.D. (1991) The Behavior Guide to African Mammals..
Famini, D., , J.R., and Kram, R. (1999) Locomotion kinematics of African elephants. American Zoologist (1999) v. 39 p.84A.
Gale U.T. (1974) Burmese Timber Elephant. Trade Corp. 9, Printer: Toppan Print, Co.
Gambaryan, P.P. (1974) How Mammals Run: Anatomical Adaptations. Wiley, New York.
Garland, T. (1983) The relation between maximal running speed and body mass in terrestrial mammals. Journal of the Zoological Society of (1983) v. 199 p. 157-70.
Gregory, W. (1912) Notes on principles of quadrupedal locomotion and the mechanisms of limbs in hoofed mammals. Annals of the New York of Sciences (1912) v. 22 p. 267-294.
Groning, K. (1998) Elephants. Kohemann Verlagsgesellschaft.
Hildebrand, M. (1985) Functional Vertebrate Morphology: Chapt. 3 - Walking and Running. The Belknap Press.
Howell, A.B. (1944) Speed in Animals. of Press, Chicago.
Hutchinson, J.R., D. Schwerda, D. Famini, R.H.I. Dale, M. Fischer, R. Kram. 2006. The locomotor kinematics of African and Asian elephants: changes with speed and size. Journal of Experimental Biology (2006) v.209 p.3812-3827.
Hutchinson, J.R., Famini, D., Lair, R., and Kram, R. (2003) Are fast-moving elephants really running? Nature (2003) v. 422 p. 493-494.
Hutchinson, J.R., Famini, D., Kram, R., and Lair, R. (2002) Do elephants run? American Zoologist v. 41 p. 1479.
Iriarte-Díaz, J. (2002) Differential scaling of locomotor performance in small and large terrestrial mammals. Journal of Experimental Biology v. 205 p.2897-2908.
Jackson, P. (1990) Endangered Species: Elephants. Chartwell Books.
Le Rue III, L. (1994) A Portrait of the Animal World. Todtri Prod. Limited, New York.
May, M. (1999) Speed demons. The Sciences (January/February 1999) p. 16-18.
McKay, G. (1973) Behavior and Ecology of the Asiatic Elephant in S.E. Asia. Smithsonian Institute Press< Washington.
Muybridge, E. (1899) Animals In Motion. Dover Publications Inc., New York.
Paul, G.S. (1998) Limb design, function and running performance in ostrich-mimics and tyrannosaurs. Gaia v. 15 p. 257-70.
Sikes, S. (1971) The Natural History of the African Elephant. American Isevier Pub. Co, New York.
Sikes, S. (1994) Elephants. T & AD Poyser Ltd.
Tennet, Sir J. E. (1867) The Wild Elephant. Longmans, Green, and co.
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Williams, J.H. (1950). Elephant Bill. Doubleday, Garden City, NY.
|
author |
year |
mph |
kph |
m/s |
comments |
|
Le Rue III |
1994 |
1 |
1.6 |
0.44 |
|
|
Alexander, S |
2000 |
2.5 |
4 |
1.11 |
Asian normal |
|
Alexander, S |
2000 |
3 |
4.8 |
1.33 |
avg. Asian speed (quotes Ivan T Sanderson |
|
Estes |
1991 |
6 to 8 |
1.6-2.2 |
avg. |
|
|
Le Rue III |
1994 |
5 |
8 |
2.22 |
from walking along side |
|
Spinage |
1994 |
6.25 |
10 |
2.78 |
African normal |
|
Alexander, R.McN. |
1979 |
8.55 |
13.68 |
3.80 |
Muybridge photos |
|
Alexander, R.McN. |
1979 |
10.13 |
16.2 |
4-4.5 |
film |
|
Paul |
1998 |
12 |
20 |
5.56 |
max; claims 19 kph from Asian in filmed race |
|
Baker |
1890 |
15 |
24 |
6.67 |
200-300 yards; Asian and African |
|
Gale |
1974 |
15 |
24 |
6.67 |
Asian max (100 yards) |
|
Spinage |
1994 |
15 |
24 |
6.67 |
African shuffling walk |
|
Alexander, S |
2000 |
15 |
24 |
6.67 |
Asian max (quotes Sanderson) |
|
Hutchinson et al. |
2003, 2006 |
15 |
24 |
6.80 |
Asian and African near-maximal speed |
|
|
1990 |
15.5 |
25 |
6.94 |
|
|
Iriarte-Díaz |
2002 |
16 |
26 |
7.00 |
Asian max |
|
Estes |
1991 |
18.75 |
30 |
8.33 |
max |
|
Spinage |
1994 |
18.75 |
30 |
8.33 |
African charging |
|
Spinage |
1994 |
20 |
32 |
8.89 |
max Asian (also says Asian is slower?!?) |
|
Iriarte-Díaz |
2002 |
21 |
34 |
9.50 |
African max |
|
|
1983 |
21.88 |
35 |
9.72 |
knockdown of Howell |
|
Breeland |
1948 |
24 |
38.4 |
10.67 |
120 yards |
|
Beebe |
1968 |
24 |
38.4 |
10.67 |
120 yards |
|
Andrews |
1937 |
24.5 |
39.2 |
10.89 |
120 yards |
|
Van Gelder |
1969 |
25 |
40 |
11.11 |
120 yards |
|
Borst |
1969 |
25 |
40 |
11.11 |
avg. speed is 4 mph |
|
|
1977 |
25 |
40 |
11.11 |
|
|
Le Rue III |
1994 |
25 |
40 |
11.11 |
charging (land rover) |
|
Groning |
1998 |
25 |
40 |
11.11 |
|
|
Alexander, S |
2000 |
30 |
48 |
13.33 |
African max |
|
Muybridge |
1899 |
see Baker |
|||
|
Howell |
1944 |
see Muybridge and Andrews |
|||
|
Bourliere |
1964 |
see Howell |
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