Abstract: As there is no statistical evidence that saddle fit influences the load exerted on a horse's back this study was performed to assess the hypothesis that the width of the tree significantly alters the pressure distribution on the back beneath the saddle. Nineteen sound horses were ridden at walk and trot on a treadmill with three saddles differing only in tree width. Kinetic data were recorded by a sensor mat. A minimum of 14 motion cycles were used in each trial. The saddles were classified into four groups depending on fit. For each horse, the saddle with the lowest overall force (LOF) was determined. Saddles were classified as “too-narrow” if they were one size (2 cm) narrower than the LOF saddle, and “too-wide” if they were one size (2 cm) wider than the LOF saddle. Saddles two sizes wider than LOF saddles were classified as “very-wide”. In the group of narrow saddles, the pressure in the caudal third (walk 0.63 N/cm2 +/- 0.10; trot 1.08 N/cm2 +/- 0.26) was significantly higher compared to the LOF saddles (walk 0.50 N/cm2 +/- 0.09; trot 0.86 N/cm2 +/- 0.28). In the middle transversal third, the pressure of the wide saddles (walk 0.73 N/cm2 +/- 0.06; trot 1.52 N/cm2 +/- 0.19) and very-wide saddles (walk 0.77 N/cm2 +/- 0.06; trot 1.57 N/cm2 +/- 0.19) was significantly higher compared to LOF saddles (walk 0.65 N/cm2 +/- 0.10/ 0.63 N/cm2 +/- 0.11; trot 1.33 N/cm2 +/- 0.22/1.27 N/cm2 +/- 0.20). This study demonstrates that the load under poorly fitting saddles is distributed over a smaller area than under properly fitting saddles, leading to potentially harmful pressures peaks.

Abstract: Humans are capable of making inferences about other individuals' intentions and goals by evaluating their actions in relation to the constraints imposed by the environment. This capacity enables humans to go beyond the surface appearance of behavior to draw inferences about an individual's mental states. Presently unclear is whether this capacity is uniquely human or is shared with other animals. We show that cotton-top tamarins, rhesus macaques, and chimpanzees all make spontaneous inferences about a human experimenter's goal by attending to the environmental constraints that guide rational action. These findings rule out simple associative accounts of action perception and show that our capacity to infer rational, goal-directed action likely arose at least as far back as the New World monkeys, some 40 million years ago.

Abstract: Two studies were conducted to determine the relationship of feeding behavior to the phenotypic expression of feed efficiency. In Exp. 1, a feedlot diet containing roughage was fed (traditional). In Exp. 2, a no-roughage diet was fed. Residual feed intake (RFI), a measure of feed efficiency, was calculated for both studies. In Exp. 1, 6 feed efficient (low RFI) steers and 6 feed inefficient steers (high RFI) were selected from a contemporary group of 80 steers, and feeding behaviors were analyzed. In Exp. 2, 9 feed efficient and 8 feed inefficient steers were selected from a contemporary group of 40 steers. There were no differences (P > 0.13) in initial or final BW or ADG between efficient and inefficient groups in either Exp. 1 or 2. In Exp. 1 DMI and average eating bouts daily differed (P < 0.001) with efficient steers consuming less feed and eating fewer times per day. In Exp. 2, efficient steers consumed less (P < 0.001) feed, and average eating bouts daily tended (P = 0.07) to be fewer in efficient animals. Limited differences were noted in feeding behavior between groups, with inefficient steers from both studies having a more variable eating pattern throughout the day. The average daily eating rate did not differ (P > 0.20) between groups in either experiment. The average number of days comprising a feeding pattern for both feed efficiency groups in Exp. 1 and 2 was found to be 2 to 3 d and multiples of 2 to 3 d. In Exp. 1 the feed intake pattern of efficient and inefficient steers changed once they reached a BW of approximately 391 kg and 381 kg, respectively. This occurred near d 47 for the efficient steers and near d 32 for inefficient steers. In Exp. 2 the feed intake pattern of both efficient and inefficient steers changed once they reached a BW of approximately 399 kg, which occurred on d 31 for the efficient steers and on d 33 for the inefficient steers. From the measured variables there were no differences in growth and limited differences noted in feeding behavior between feed efficient and feed inefficient groups. The results of the trials suggest increased variability of feed intake throughout the day for feed inefficient animals.

Abstract: About the Book
“Few can rival what Rolf Peterson has accomplished on Isle Royale. His study, a true classic, offers lessons and examples to us all who hope to do the same. This book reveals some of the secrets and details of this one-of-a-kind wolf study.”
-Douglas W. Smith, Leader, Yellowstone Wolf Project
For nearly half a century Isle Royale National Park has been the site of a comprehensive study on wolves (2008 marks the fiftieth anniversary)-the world's longest-running study on any wild animal. With its lush northern landscape and wolf and moose populations, the pristine and isolated park presents an ideal laboratory for wildlife biologists.
The Wolves of Isle Royale is author and wildlife biologist Rolf Peterson's fascinating firsthand account of the relationship that exists between the wolf and the moose on the island. Illustrated with over 100 photographs, this book reveals the true nature of the mysterious and little-understood wolf, and it offers novel solutions to the conservation crisis as the wolf population falters to its lowest recorded level.
Rolf O. Peterson is known worldwide for his wolf research. His photographs have been published in National Geographic, Audubon, and National Wildlife. He is Professor of Wildlife Ecology at Michigan Technological University.
Cover photo credit: Rolf O. Peterson

Abstract: Time-space learning reflects an ability to represent in memory event-stimulus properties together with the place and time of the event; a capacity well developed in birds. Homing pigeons were trained in an indoor octagonal arena to locate one food goal in the morning and a different food goal in the late afternoon. The goals differed with respect to their angular/directional relationship to an artificial light source located outside the arena. Further, the angular difference in reward position approximated the displacement of the sun's azimuth that would occur during the same time period. The experimental birds quickly learned the task, demonstrating the apparent ease with which birds can adopt an artificial light source to discriminate among alternative spatial responses at different times of the day. However, a novel midday probe session following successful learning revealed that the light source was interpreted as a stable landmark and not as a surrogate sun that would support compass orientation. Probe sessions following a phase shift of the light-dark cycle revealed that the mechanism employed to make the temporal discrimination was prevailingly based on an endogenous circadian rhythm and not an interval timing mechanism.