Imitation of facial gestures by an infant chimpanzee

A nursery-reared infant chimpanzee (Pan troglodytes) was tested for the ability to imitate human facial gestures, following the procedure ofMeltzoff andMoore (1977). The subject was observed between 5 to 15 weeks of ages. The results showed that the subject could imitate tongue protrusion in the age of 5–10 weeks and mouth opening between the ages of 5–11 weeks. However, from 12 to 15 weeks, the infant did not imitate the facial gestures. The present study clearly demonstrated that the infant chimpanzee could imitate human facial gestures in a particular period.     

Coxsackievirus in an infant chimpanzee.

Coxsackie B viruses may cause a severe, often fatal, illness in newborn and infant human subjects. As recorded in this case, infant chimpanzees respond similarly to Coxsackie B-5 virus.     

A case of the adoption of an infant chimpanzee by a suckling foster chimpanzee

Chimpanzees in captivity have grown up in a rather unnatural social environment and there frequently are problems when they have to nurse their own offspring. It is most remarkable that a chimpanzee mother in a captive colony, who had lost her child almost immediately after birth, adopted without problems a five-week-old infant, which had been reared by humans from the day of its birth. Successful adoption has not been reported for feral chimpanzees; similar cases in captivity are not known.     

Ventricular septal defect in an infant chimpanzee (Pan troglodytes)

During clinical examinations and imaging studies of a prematurely born chimpanzee, a heart murmur, tachypnea, dyspnea, and disturbances of blood flow were observed. At necropsy, cardiomegaly, ventricular hypertrophy, and septal defects confirmed the presence of congenital VSD.     

Treatment of myocardial dysfunction and pulmonary oedema in an infant chimpanzee

Abstract: The care of any critically ill infant requires special technical equipment for monitoring of cardiac and pulmonary functions including mechanical ventilators and blood gas analysers. The present paper describes the treatment of myocardial dysfunction and pulmonary distress, complicated by severe brain oedema in an infant chimpanzee admitted to an intensive care unit in the Department of Neonatology of the Children's Hospital of the University of Leipzig. The condition of the chimpanzee was diagnosed and monitored by standard clinical tooös including radiography, echocardiography, cerebral Doppler sonography and laboratory parameters. The chimpanzee was treated in close cooperation between veterinarians and paediatricians.     

Preference for an estrous female over a non-estrous female evinced by female rats requires dihydrotestosterone plus estradiol

The effects were studied of long-term treatment with testosterone metabolites (dihydrotestosterone, DHT, and estradiol, E2, in sc Silastic implants) on preference behavior of ovariectomized female rats for an estrous female over a non-estrous female. For measuring this behavior a residential plus-maze was used which harbored two ovariectomized “stimulus” females on the top of peripheral boxes, one of which was made estrus by injection of estradiol benzoate and progesterone. When both steroids (DHT plus E2) were circulating simultaneously they evoked preference for an estrous female, while neither steroid by itself sufficed. In earlier work with adult male rats castrated on the day of birth, E2 was effective in the absence of DHT. This sex difference, therefore, seems to have arisen before birth. Further, administration of DHT alone caused a profound lack of interest in both “stimulus” females, which cannot be fully explained by the reduced locomotor activity which has been found to be induced by DHT in earlier Studies.     

Wild chimpanzee infant urine and saliva sampled noninvasively usable for DNA analyses

In many genetic studies on the great apes, fecal or hair samples have been used as sources of DNA. However, feces and hairs are difficult to collect from chimpanzee infants under 3 years of age. As alternative DNA sources, we investigated the efficiency of collecting urine samples from infants compared with fecal samples, as well as the validity of the DNA extracted from urine and saliva samples of well-habituated M group chimpanzees (Pan troglodytes schweinfurthii) in the Mahale Mountains National Park, Tanzania. We collected 40 urine and 3 fecal samples from 10 infants under 3 years. Compared with feces, the urine samples were relatively easy to collect. The saliva of infants, which remained on the twigs sucked by them, was collected using cotton swabs. The average amounts of DNA extracted from the 40 urine and 6 saliva samples were 3,920 and 458 pg/μl, respectively. The rate of positive PCR was low and the allelic dropout rate was high when using less than 25 pg of template DNA in the PCR mixtures. Based on the amounts of DNA, 50% of the urine samples and 100% of the saliva samples were judged usable for accurate microsatellite genotyping. For infant chimpanzees in particular, collecting urine and saliva as an alternative to fecal and hair samples can reduce the effort invested in collection in the field.     

Fatal attack on an infant by an adult female tonkean macaque

We describe a fatal attack on a 10-month-old female infant by an adult female Tonkean macaque (Macaca tonkeana)in a semi-free-ranging group. During an intense conflict involving many group members, an adult female, the second most dominant in the group, attacked the infant of a lower-ranking female. The attacker remained near the victim for approximately 20 min, grabbing and biting it repeatedly, until the mother retrieved the infant. She died 2 days later. An autopsy revealed no lethal injury;the main cause of death was starvation or dehydration or both. We discuss social conditions under which a fatal attack by an adult female might occur.     

Preference for and Discrimination of Paintings by Mice

I measured preference for paintings (Renoir vs. Picasso or Kandinsky vs. Mondrian) in mice. In general mice did not display a painting preference except for two mice: one preferred Renoir to Picasso, and the other preferred Kandinsky to Mondrian. Thereafter, I examined discrimination of paintings with new mice. When exposure to paintings of one artist was associated with an injection of morphine (3.0 mg/kg), mice displayed conditioned preference for those paintings, showing discrimination of paintings by Renoir from those by Picasso, and paintings by Kandinsky from those by Mondrian after the conditioning. They also exhibited generalization of the preference to novel paintings of the artists. After conditioning with morphine for a set of paintings consisting of two artists, mice showed discrimination between two sets of paintings also from the two artists but not in association with morphine. These results suggest that mice can discriminate not only between an artist’s style but also among paintings of the same artist. When mice were trained to discriminate a pair of paintings by Kandinsky and Renoir in an operant chamber equipped with a touch screen, they showed transfer of the discrimination to new pairs of the artists, but did not show transfer of discrimination of paintings by other artists, suggesting generalization.     

Effective use of a joystick by an infant monkey

The acquisition of the ability to use a joystick to maintain contact between a cursor and moving target is described for an infant bonnet macaque (Macaca radiata). The infant was first exposed to a very elementary joystick task while living in a social group at the age of 3.5 months. With task difficulty increased in small increments over a total of only 9 weeks of access to the tasks, the infant was able to maintain contact with a small moving target for over 2.5 sec by the age of 7.5 months. © 1994 Wiley-Liss, Inc.     

Preference for ribose over deoxyribose in loop-closing base pairs of extra stable nucleic acid hairpins

We have investigated the effect of switching ribose to deoxyribose at the closing base-pair of an extra-stable RNA hairpin. Specifically, we studied the sequence 5'-GGAC(UUCG)GUCC, a dodecanucleotide that folds into a well-characterized, "extra stable" RNA hairpin structure. Recently, we showed that hairpins containing a 2',5'-linked (UUCG) loop instead of the native 3',5'-linked loop also exhibit extra-stability (Hannoush and Damha, J. Am. Chem. Soc., 2001, 123, 12368-12374). In this article, we show that the ribose units located at the loop-closing positions (i.e., rC4 and rG9) contribute significantly to the stabilization of RNA hairpins, particularly those containing the 3',5'-UUCG loop. Interestingly, the requirement of rC4 and rG9 is more relaxed for DNA hairpins containing the 2',5'-UUCC loop and, in fact, they may be replaced altogether (ribose--> deoxyribose) without affecting stability. The results broaden our understanding of the behavior of highly stable (UUCG) hairpin loops and how they respond to structural perturbation of the loop-closing base pairs.     

The Development of a Preference for Cocaine over Food Identifies Individual Rats with Addiction-Like Behaviors

Rationale

Cocaine dependence is characterized by compulsive drug taking that supercedes other recreational, occupational or social pursuits. We hypothesized that rats vulnerable to addiction could be identified within the larger population based on their preference for cocaine over palatable food rewards.

Objectives

To validate the choice self-administration paradigm as a preclinical model of addiction, we examined changes in motivation for cocaine and recidivism to drug seeking in cocaine-preferring and pellet-preferring rats. We also examined behavior in males and females to identify sex differences in this “addicted” phenotype.

Methods

Preferences were identified during self-administration on a fixed-ratio schedule with cocaine-only, pellet-only and choice sessions. Motivation for each reward was probed early and late during self-administration using a progressive-ratio schedule. Reinstatement of cocaine- and pellet-seeking was examined following exposure to their cues and non-contingent delivery of each reward.

Results

Cocaine preferring rats increased their drug intake at the expense of pellets, displayed increased motivation for cocaine, attenuated motivation for pellets and greater cocaine and cue-induced reinstatement of drug seeking. Females were more likely to develop cocaine preferences and recidivism of cocaine- and pellet-seeking was sexually dimorphic.

Conclusions

The choice self-administration paradigm is a valid preclinical model of addiction. The unbiased selection criteria also revealed sex-specific vulnerability factors that could be differentiated from generalized sex differences in behavior, which has implications for the neurobiology of addiction and effective treatments in each sex.     

Incestuous Sisters: Mate Preference for Brothers over Unrelated Males in Drosophila melanogaster

The literature is full of examples of inbreeding avoidance, while recent mathematical models predict that inbreeding tolerance or even inbreeding preference should be expected under several realistic conditions like e.g. polygyny. We investigated male and female mate preferences with respect to relatedness in the fruit fly D. melanogaster. Experiments offered the choice between a first order relative (full-sibling or parent) and an unrelated individual with the same age and mating history. We found that females significantly preferred mating with their brothers, thus supporting inbreeding preference. Moreover, females did not avoid mating with their fathers, and males did not avoid mating with their sisters, thus supporting inbreeding tolerance. Our experiments therefore add empirical evidence for inbreeding preference, which strengthens the prediction that inbreeding tolerance and preference can evolve under specific circumstances through the positive effects on inclusive fitness.