African elephants

Moss, C.J. 1996. Getting to know a population. In K. Kangwana (Ed.), Studying Elephants. African Wildlife Foundation, Nairobi, Kenya, pp. 58-74. 

Vogel, J.C., Talma, A.S., Hall-Martin, A.J. and Viljoen, P.J. 1990 Carbon and nitrogen isotopes in elephants. South African Journal of Science 86 147-150. 

Fig. 7.4(b) Palate of foetal African Elephant reception area for finger of trunk (PI. 7.1) and for uptake of protein-bound signal complexes. PS, palatine sulcus and pp, palatine pits PR, ridges (from Eales, 1926). 

Eales N.B. (1926). The anatomy of the head of a foetal African elephant. Phil Trans Roy Soc Edin LIV(III), 491-547. 

Poole J. (1987). Rutting behavior in African elephants — the phenomenon of musth. Behaviour 102, 283-316. 

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. 

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. 

Rasmussen, L.E.L. and Wittemyer, G. (2002) Chemosignaling of musth by individual wild African elephants, (Loxodonta africana). implications for conservation and management. Proc. Royal Soc. London 269, 853-860. 

Rasmussen, L.E.L., Hall-Martin, A.J. and Hess, D.L. (1996) Chemical profiles of male African elephants, Loxodonta africana Physiological and ecological implications. J. Mammal. 77, 422-439. 

Riddle, H.S., Riddle, S.W., Rasmussen, L.E.L. and Goodwin, T.E. (2000) The first disclosure and preliminary investigation of a liquid released from the ears of African elephants. Zoo Biol. 19, 475—480. 

Use of Automated Solid Phase Dynamic Extraction (SPDE)/GC-MS and Novel Macros in the Search for African Elephant Pheromones ... 

Abstract A relatively small number of mammalian pheromones has been identified, in contrast to a plethora of known insect pheromones, but two remarkable Asian elephant/insect pheromonal linkages have been elucidated, namely, (Z)-7-dodecen-1-yl acetate and frontalin. In addition, behavioral bioassays have demonstrated the presence of a chemical signal in the urine of female African elephants around the time of ovulation. Our search for possible ovulatory pheromones in the headspace over female African elephant urine has revealed for the first time the presence of a number of known insect pheromones. This search has been facilitated by the use of a powerful new analytical technique, automated solid phase dynamic extraction (SPDE)/GC-MS, as well as by novel macros for enhanced and rapid comparison of multiple mass spectral data files from Agilent ChemStation . This chapter will focus on our methodologies and results, as well as on a comparison of SPDE and the more established techniques of solid phase microextraction (SPME) and stir bar sorptive extraction (SBSE). 

Fig. 2.1 Compounds identified in female African elephant urine headspace that are known insect pheromones...

Use of SPDE/GC-MS for Analysis of African Elephant Urine Headspace... 

Use of automated headspace SPDE/GC-MS not only enabled the identification in female African elephant urine of a number of known insect pheromones (compounds 2-6, Fig. 2.1), but also revealed the presence of the beetle biochemical precursors to frontalin (2), exo-brevicomin (3) and ent/o-brevicomin (4), thus suggesting a common biosynthetic pathway (Goodwin et al. 2006). Extensive behavioral bioassays must be performed to determine whether any of these compounds is functioning as a pheromone among African elephants. 

Schulte, B.A., Bagley, K.R., Groover, M., Loizi, H., Merte, C., Meyer, J.M., Napora, E., Stanley, L., Vyas, D.K., Wollett, K., Goodwin, T.E. and Rasmussen, L.E.L. (2007) Comparisons of state and likelihood of performing chemosensory event behaviors in two populations of African elephants (Loxodonta africana). In J. Hurst, R. Beynon, C. Roberts and T. Wyatt (Eds.), Chemical Signals in Vertebrates 11. Springer Press, New York, pp. 70-79. 

Comparisons of State and Likelihood of Performing Chemosensory Event Behaviors in Two Populations of African Elephants (Loxodonta africanaf... 

The purpose of the current study was to compare the state and chemosensory behaviors of African elephants at our two African study sites. While similarity in these behaviors does not guarantee that chemical signals will be identical in structure and function, the absence of large differences would suggest that such a situation is probable. 

One of our field sites involves free-ranging African elephants at Ndarakwai Ranch, Tanzania. Ndarakwai Ranch is a privately owned area of ca. 4300 ha located in northern Tanzania. The habitat is a mix of grassland and mixed acacia woodland. This region typically experiences annually a short and a long wet season separated by dry seasons (Vyas 2006), similar to nearby Amboseli National Park, where rainfall averages 350 mm annually (Poole 1999). 

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