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Gallistel, C. R., & Cramer, A. E. (1996). Computations on metric maps in mammals: getting oriented and choosing a multi-destination route. J Exp Biol, 199(Pt 1), 211–217.
Abstract: The capacity to construct a cognitive map is hypothesized to rest on two foundations: (1) dead reckoning (path integration); (2) the perception of the direction and distance of terrain features relative to the animal. A map may be constructed by combining these two sources of positional information, with the result that the positions of all terrain features are represented in the coordinate framework used for dead reckoning. When animals need to become reoriented in a mapped space, results from rats and human toddlers indicate that they focus exclusively on the shape of the perceived environment, ignoring non-geometric features such as surface colors. As a result, in a rectangular space, they are misoriented half the time even when the two ends of the space differ strikingly in their appearance. In searching for a hidden object after becoming reoriented, both kinds of subjects search on the basis of the object's mapped position in the space rather than on the basis of its relationship to a goal sign (e.g. a distinctive container or nearby marker), even though they have demonstrably noted the relationship between the goal and the goal sign. When choosing a multidestination foraging route, vervet monkeys look at least three destinations ahead, even though they are only capable of keeping a maximum of six destinations in mind at once.
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Etienne, A. S., Maurer, R., & Seguinot, V. (1996). Path integration in mammals and its interaction with visual landmarks. J Exp Biol, 199(Pt 1), 201–209.
Abstract: During locomotion, mammals update their position with respect to a fixed point of reference, such as their point of departure, by processing inertial cues, proprioceptive feedback and stored motor commands generated during locomotion. This so-called path integration system (dead reckoning) allows the animal to return to its home, or to a familiar feeding place, even when external cues are absent or novel. However, without the use of external cues, the path integration process leads to rapid accumulation of errors involving both the direction and distance of the goal. Therefore, even nocturnal species such as hamsters and mice rely more on previously learned visual references than on the path integration system when the two types of information are in conflict. Recent studies investigate the extent to which path integration and familiar visual cues cooperate to optimize the navigational performance.
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Thor, D. H., & Holloway, W. R. (1982). Social memory of the male laboratory rat. J. Comp. Physiol. Psychol., 96(6), 1000–1006.
Abstract: Used duration of social-investigatory behavior by 36 mature male Long-Evans rats as a measure of individual recognition in 5 experiments to assess social memory. In Exp I, the duration of social investigation during a 2nd exposure to the same juvenile (n[en space]=[en space]12) was directly related to the length of the interexposure interval. In Exp II, Ss were exposed to the same or different juvenile 10 min after an initial 5-min exposure to a novel juvenile; reexposure to the same juvenile elicited significantly less social investigation than an exposure to a different juvenile. Exps III and IV demonstrated that following a 5-min introductory exposure, social memory of the juvenile was relatively brief in comparison with that of mature Ss. Exp V revealed a retroactive interference effect on recently acquired memory for an individual: 12 mature Ss exposed to interpolated social experience engaged in significantly longer investigation of a juvenile than those with no interpolated social experience. The combined results suggest that (1) the rat normally engages in spontaneous learning of individual identity and (2) social memory may be a significant aspect of complex social interactions. (16 ref) (PsycINFO Database Record (c) 2006 APA, all rights reserved)
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Steiner, M. (1982). Biomechanics of tendon healing. J Biomech, 15(12), 951–958.
Abstract: The biomechanics of tendon healing was investigated with unsutured rat achilles tendons. After two, three, and four weeks of healing tensile parameters were assayed with a bone-muscle-tendon-bone preparation elongated to failure at a controlled physiological strain rate. In the third week of healing, stiffness, strength, and energy absorbing capacity all increased approximately 50%. These changes correlated with early fibroplasia. In the fourth week of healing, strength, energy absorbing capacity and elongation to failure all increased relatively more than stiffness. Histologically, larger fibers with better longitudinal alignment developed during this period. At the end of four weeks the tendon's strength was approximately 25% of normal. To summarize, the return of stiffness in a healing tendon preparation correlated with the presence of fibroplasia and the return of other tensile parameters was a function of the amount and organization of the fibroplasia.
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Yokoyama, S., & Radlwimmer, F. B. (1999). The molecular genetics of red and green color vision in mammals. Genetics, 153(2), 919–932.
Abstract: To elucidate the molecular mechanisms of red-green color vision in mammals, we have cloned and sequenced the red and green opsin cDNAs of cat (Felis catus), horse (Equus caballus), gray squirrel (Sciurus carolinensis), white-tailed deer (Odocoileus virginianus), and guinea pig (Cavia porcellus). These opsins were expressed in COS1 cells and reconstituted with 11-cis-retinal. The purified visual pigments of the cat, horse, squirrel, deer, and guinea pig have lambdamax values at 553, 545, 532, 531, and 516 nm, respectively, which are precise to within +/-1 nm. We also regenerated the “true” red pigment of goldfish (Carassius auratus), which has a lambdamax value at 559 +/- 4 nm. Multiple linear regression analyses show that S180A, H197Y, Y277F, T285A, and A308S shift the lambdamax values of the red and green pigments in mammals toward blue by 7, 28, 7, 15, and 16 nm, respectively, and the reverse amino acid changes toward red by the same extents. The additive effects of these amino acid changes fully explain the red-green color vision in a wide range of mammalian species, goldfish, American chameleon (Anolis carolinensis), and pigeon (Columba livia).
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Graham, M., & Letz, R. (1979). Within-species variation in the development of ultrasonic signaling of preweanling rats. Dev Psychobiol, 12(2), 129–136.
Abstract: The development of litter and individual differences in the rate of ultrasonic signaling of neonatal rats was studied. Systematic variations among litters and individuals emerged, without differential treatment. These differences were not correlated with variations in general development as indexed by body weight. Two experiments using a cross-fostering design showed that litter differences developed independently of variations in postnatal environment. These results indicate that the variations among litters in ultrasound rate have a prenatal, possibly genetic, etiology and may represent reliable indicants of response to environmental stress.
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Alexander, F., & Davies, M. E. (1969). Studies on vitamin B12 in the horse. Br. Vet. J., 125(4), 169–176.
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Schmoldt, A., Benthe, H. F., & Haberland, G. (1975). Digitoxin metabolism by rat liver microsomes. Biochem Pharmacol, 24(17), 1639–1641.
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Cowley, J. J., & Griesel, R. D. (1966). The effect on growth and behaviour of rehabilitating first and second generation low protein rats. Anim. Behav., 14(4), 506–517.
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Christensen, H. A., & Herrer, A. (1973). Attractiveness of sentinel animals to vectors of leishmaniasis in Panama. Am J Trop Med Hyg, 22(5), 578–584.
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