Elephants Rasmussen

The edulans and dihydroedulans were first identified in passionfruit (Whitfield and Stanley, 1977 Prestwich et al., 1976). Subsequently, edulans were seen in human urine (Mills and Walker, 2001), while dihydroedulans have also been found in male scent organs of African butterflies (Schulz et al., 1993). The theaspiranes have been identified in green and black tea, as well as in a number of finits and berries (Schmidt et al., 1992). Later, a theaspirane was observed by SPME/GC-MS in urine from a female Asian elephant (Rasmussen, 2001). Recently, a dihydroedulan and a theaspirane were reported from giant panda urine (Dehnhard et al., 2003). 

The flehmen trunk movement is easy to differentiate from other trunk movements irrespective of elephant species or sex. Variation in the duration and frequency of flehmen may be dependent on the chemical sample or perhaps on the particular style of an individual elephant (Rasmussen, unpubl. data). Check and place responses also are distinct. Because African elephants have two trunk tip fingers, compared to one for the Asian species, checks can be more variable for the African species (i.e., anterior, posterior or simultaneous checks are possible). Behaviorally, the multiple positions in which the trunk moves for sniffing are perhaps the most intriguing types of variation. As defined for a bioassay scenario, a sniff occurs when the trunk hovers over a sample that we place on the ground (Figure 1). This is the most direct means by which an elephant... 

Fig. 2.17 Microvilli in Asian Elephant ( 1 maximus), lumen surface. VNOR with branched and unbranched organelles tip of supporting cell (from Rasmussen and Hultgrcn, 1990).

In rabbits, the as yet unidentified maternal signal during lactation has analogous properties in guiding the reliable orientation of suckling, mainly via MOS input (Hudson and Distel, 1986 Schaal et al., unpubl.). Minor fractions may still function as flag contributors, exemplified by the attractiveness of proestrous elephant urine. Male responses show that intact urine is conspicuously more attractive in comparison with the pure insect mammal pheromone (9.) presented in water (Rasmussen et al., 1996). 

Fig. 7.4(a) Chemoinvestigation with F. in male Indian Elephant L, Sampling of urino-genital secretions (in situ) with trunk-tip (pre-Flehmen) => R. trunk (and upper-lip) curl, sample placed on palate => (b. below) (after Eisenberg et al, 1971 after Rasmussen et al., 1982). 

PI. 7.1 Nasal chemosampling, trunk-tip of Asian Elephant anterior finger region, showing tactile area + pits (DT, arrows). Vibrissa hairs (LVH and SVH), muscular walls (LDT and VT) (from Rasmussen and Munger, 1996). 

Perrin T. and Rasmussen L.E.L. (1994). Chemosensory responses of female Asian elephants (Elephas maximus) to cyclohexanone. J Chern Ecol 20, 2953-2958. 

Rasmussen L.E.L. and Hultgren B. (1990). Gross and microscopic anatomy of vomeronasal organ in the Asian Elephant (Elephas maximus). In Chemical Signals in Vertebrates 5 (MacDonald D., Milller-Schwarze D. and Natynczuk S.E., eds.). Oxford University Press, pp. 154-161. 

Rasmussen L.E.L., Lee T.D., Daves G. and Schmidt M.J. (1993). Female-to-male sex-pheromones of low volatility in the Asian Elephant, Elephas maximus. J Chem Ecol 19, 2115-2128. 

Rasmussen L.E.L. and Munger B.L. (1996). The sensorineural specializations of the trunk tip (finger) of the Asian elephant, Elephas maximus. Anat Rec 246, 127-134. 

Rasmussen L.E.L., Schmidt M.J. and Daves G. (1982). Asian bull elephants Flehmen-like responses to extractable components of female elephant estrus urine. Science 217, 159-162. 

Rasmussen L.E.L. and Schulte B. (1998). Chemical signals in the reproduction of Asian (Elephas maximus) and African (Loxodonta africana) elephants. Anim Reprod Sci 53, 19-34. 

On September 17, 2006, the world lost a great scientist, the world s elephants lost a tireless benefactor, and we lost a superb collaborator, wise mentor, and dear friend. Dr. L.E.L. Bets Rasmussen was a wonderful and remarkable human being, with an infectious joie de vivre, boundless energy, a brilliant and probing intellect, an insatiable curiosity about nature, and an impish wit. She was clearly the world s leading authority on chemical communication among elephants, and a leader in the study of elephant biochemistry. 

Bets was enamored with the signals involved in musth, and in their evolution (Rasmussen 1998 Rasmussen and Schulte 1998 Rasmussen 1999). She collaborated with many young researchers in her pursuit of a better understanding of musth in Asian and African elephants (e.g., Perrin and Rasmussen 1994 Rasmussen and Perrin 1999 Schulte and Rasmussen 1999a Rasmussen and Wittemyer 2002). As a Research Professor at OGI, Bets had the intellectual freedom to pursue a variety of research topics and collaborate with numerous individuals however, she was away on research ventures so often that overseeing students was not easy. One of the authors of this tribute (B.A.S.) was fortunate to have a recommendation from his major professor, Dietland Miiller-Schwarze, which... 

Our recent NSF-funded collaboration with Bets has yielded, for example, the first statistically significant evidence that male African elephants can distinguish conspecific female urine collected at the time of ovulation from urine obtained at the mid-luteal time of the estrous cycle (Bagley, Goodwin, Rasmussen and Schulte 2006). Additionally, we have published the first report of insect pheromones in the urine of female African elephants (Goodwin, Eggert, House, Weddell, Schulte and Rasmussen 2006). These findings bode well for the eventual discovery of the first African elephant pheromones. 

Bagley, K.R., Goodwin, T.E., Rasmussen, L.E.L. and Schulte, B.A. (2006) Male African elephants (Loxodonta africana) can distinguish oestrous status via urinary signals. Anim. Behav. 71, 1439-1445. 

Buss, I.O., Rasmussen, L.E. and Smuts, G.L. (1976) The role of stress and individual recognition in the function of the African elephant s temporal gland. Mammalia 40, 437—451. 

Johnson, E.W. and Rasmussen, L.E.L. (2002) Morphological characteristics of the vomeronasal organ of the newborn Asian elephant, Elephas maximus. Anat. Rec. 267, 252-59. 

Lazar, J., Greenwood, D.R., Rasmussen, L.E.L. and Prestwich, G.D. (2002) Molecular and functional characterization of an odorant binding protein of the Asian elephant, Elephas maximas Implications for the role of lipocalins in mammalian olfaction. Biochemistry 41, 11786-11794. 

Rasmussen, L.E.L. (1999) Evolution of chemical signals in the Asian elephant, Elephas maximus behavioural and ecological influences. J. Biosci. (Bangalore) 24, 241-251. 

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