Sexual behaviour and its olfactory control in the desert woodrat (Neotoma lepida lepida)

In studies 1 and 2 nine pairs of desert woodrats (Neotoma lepida lepida) were observed for copulatory behaviour when the female was in a state of naturally occurring oestrus (study 1) and following ovariectomy and oestrogen and progesterone replacement (study 2). Males and females respond in a similar way under conditions of natural and hormone-induced oestrus. Males show a consummatory pattern involving multiple mounts and ejaculations, with ejaculations occurring after single intromissions. Females show the lordosis reflex accompanied by hop-and-dart and ear-wiggling responses. In addition, both sexes show appetitive precopulatory behaviours; the male emits an audible rasping vocalization as he trails and mounts the female, following a period of intense sniffing of the female's anogenital region. The female also frequently approaches and sniffs the male. In study 3, the role of female odours in the sexual behaviour of the male was examined in eight of the nine pairs used in studies 1 and 2. This was done by applying to the anogenital region of ovariectomized females a combination of urine and vaginal secretions taken from familiar and unfamiliar, and oestrogen-primed or non-oestrogen-primed females. The results show that odours from oestrogen-primed females are not sufficient to elicit male sexual behaviour, if the female is not sexually active. In study 4 the eight males were tested for their preferences for urine and vaginal secretion odours taken from females in different reproductive states and applied to cotton swabs. These males spent more time sniffing unfamiliar oestrous odours than unfamiliar non-oestrous odours and more time sniffing oestrous odours from a familiar female over those taken from an unfamiliar female.In study 5, 12 sexually active males were tested with oestrogen-primed females before and after either olfactory bulb removal or sham-surgery. Bulbectomized animals ceased copulating with females although females showed precopulatory approaches.Taken together, these studies suggest that normal sexual behaviour in the male woodrat requires that the female both possess the attractive odours (of oestrus) and that she engage in appetitive precopulatory behaviour.     

Social organization in the dusky-footed woodrat (Neotoma fuscipes): A field and laboratory study

The dusky-footed woodrat has been characterized as solitary and asocial. In this research I sought to determine some of the parameters of woodrat social organization. In the field, I live trapped, marked and released members of a distinct group of woodrats at bi-weekly intervals from February to June. Twenty-two residents were identified and 21 out of 34 houses were found to be occupied. Visiting occurred regularly, most often at non-occupied houses. Males were unlikely to be visited at their house and were more likely to visit occupied houses than females. Females were visited at home and visited each other. In June the population was removed to the laboratory where paired encounters with familiar and unfamiliar woodrats were used to examine the effect of sex and familiarity on social interactions. Both females and males interacted little with familiar same sex conspecifics, with the behaviour of one member of such pairs being very inhibited. Females with strange females were more interactive and spent more time in contact. Neither sex clearly differentiated between familiar and strange conspecifics of the opposite sex. Males were agonistic or affiliative in encounters with females. The type of response was consistent for a given male, and females responded differently to the two types. It is concluded that woodrats differentiate between same sex conspecifics and show sufficient individual variability to make individual recognition possible and adaptive.     

The influence of sex,sexual condition and age on the exploratory behaviour of wild wood mice (Apodemus Sylvaticus L.)

From April 1978 to April 1980 the exploratory behaviour of more than 1000 wild wood mice was studied in a modified open field test situation. The influence of sex, sexual condition and age on the exploratory activity was investigated. Sufficient data being available, the exploratory activity of both sexually active and sexually inactive adult males and adult females, of both sexually active and sexually inactive subadult males and subadult females and of both sexually inactive juvenile males and females was compared by means of a one way analysis of variance for each two-month period. In other analyses the influence of age of adult males and adult females on the exploratory behaviour was further examined. No differences could be found in the exploratory activity displayed by males or females and by sexually active or sexually inactive animals. Also a clear influence of age was absent. The interindividual variation was very large.     

Copulatory behaviour and the process of intromission in Anastrepha ludens (Diptera: Tephritidae)

Complex genitalia occur in many arthropods and in some species extreme female morphologies lead to serious mechanical difficulties for males. Tephritid flies offer examples of such complex genitalia. Because of their economic importance and the extensive use of sterile male releases for tephritid control in Texas and Mexico, studies have been done on various aspects of their basic reproductive biology, but the process of intromission has received little attention. The distiphallus of the male of Anastrepha ludens is complex. One membranous sac on the distiphallus is capable of rhythmic cycles of inflation and deflation. Inflations of the sac near the base of the distiphallus probably help propel the aedeagus deeper into the female along with stiffening of the basiphallus and may drive the genital rod (which does not transfer sperm) into the ventral receptacle. We were unable to establish an association between some of the behaviours displayed by males during mating and intromission process.     

The karyotype of the golden monkey (Rhinopithecus r. roxellanae)

In this paper, the karyotype and G-banding pattern of the chromosomes of cultured peripheral blood lymphocytes in R. r. roxellanae were investigated. The chromosome number of this species is 44 in both sexes. In R. r. roxellanae, as in other monkeys, sex is determined by specific sex chromosomes, i.e. the male is XY and the female is XX. The 21 pairs of autosomes consist of 7 pairs of metacentric chromoomes, 13 pairs of submetacentric chromosomes and one acrocentric pair. Chromosome measurements were made from highly enlarged photographic prints. They included the relative length, arm ratio and centromere index of each chromosome. Both chromosomal and chromatid aberrations were observed. They were 0·67 and 2%, respectively. Finally, G-banding pattern analysis of chromosomes of R. r. roxellanae were carried out. The results show that each homologous pair has its own special banding pattern, so that each of them is easily recognizable. Idiograms of chromosome complements with the Giemsa banding pattern are constructed.     

Copulatory behaviour and differential reproduction of laboratory rats in a two-male,one-female competitive situation

In order to relate copulatory behaviour to differential reproductiion, 20 Long-Evans and 20 F344 male rats were observed in both one-male and two-male tests with an F344 female. Copulatory behaviour was quite similar in the two conditions, although there were some quantitative differences. Little fighting occurred. Long-Evans males attained 56% of the ejaculations and sired 76% of the offspring. The first male to ejaculate gained no advantage with respect to siring offspring. By contrast, the male ejaculating last or most frequently gained a significant reproductive advantage. Far from being wasted activity, persistent copulation in male rats plays an integral role in differential reproduction.     

Superovulation and embryo transfer in wood bison (Bison bison athabascae)

Two experiments were done to develop an effective superovulatory treatment protocol in wood bison for the purpose of embryo collection and transfer. In experiment 1, donor bison were assigned randomly to four treatment groups (N = 5 per group) to examine the effects of method of synchronization (follicular ablation vs. estradiol-progesterone treatment) and ovarian follicular superstimulation (single slow-release vs. split dose of FSH). Recipient bison were synchronized with donor bison by either follicular ablation (N = 8) or estradiol-progesterone treatment (N = 9). In experiment 2, bison were assigned randomly to four treatment groups (N = 5 per group) to examine the ovarian response to two versus four doses of FSH, and the effect of progesterone (ovarian superstimulation with or without an intravaginal progesterone-releasing device). Donor bison were inseminated with fresh chilled wood bison semen 12 and 24 hours after treatment with GnRH (experiment 1) or LH (experiment 2). The ovarian response was assessed using ultrasonography. In experiment 1, the number of large follicles (≥7 mm) increased in response to both FSH treatments, but the diameter of the largest follicle detected 4 and 5 days after the start of ovarian superstimulation was greater in bison treated with a single dose of FSH than in those treated with two doses (P < 0.05). A total of 10 ova and/or embryos were collected. One blastocyst was transferred to each of five recipient bison resulting in the birth of two live wood bison calves. In experiment 2, two doses of FSH resulted in a greater number of large follicles (≥9 mm) on Days 4, 5, and 6 (P < 0.05) after beginning of superstimulation (Day 0), and more ovulations than four doses of FSH (11.2 ± 2.4 vs. 6.4 ± 0.8; P < 0.05). Embryo collection was performed on only five donors, and a total of 19 ova and/or embryos were recovered. In summary, fewer FSH treatments were as good or better than multiple treatments, consistent with the notion that minimizing handling stress improves the superovulatory response in bison. Follicular ablation and estradiol plus progesterone treatment were effective for inducing ovarian synchronization in embryo donor and recipient bison, and an intravaginal progesterone-releasing device during superstimulatory treatment did not influence the superovulatory response or embryo collection. Delaying ovulation-inducing treatment (GnRH or LH) to 5 days after superstimulatory treatment resulted in a greater number of ovulations and improved embryo collection efficiency (experiment 2). Embryo collection and transfer resulted in live offspring from wild wood bison.     

The behaviour and ecology of wild orang-utans (Pongo pygmaeus)

Between June 1968 and November 1971, 21 months of fieldwork were spent studying wild populations of orang-utans in Borneo and Sumatra. Fifteen hundred hours of daylight observation were made on these animals. In contrast to other higher primates, the dispersed distribution of food and the orang-utan's slow mode of travel seem to favour solitary habits. Over, 80 per cent of foraging units seen contined only one independent animal, either alone or with dependent young. Larger groupings were seen when adolescents joined up with other animals or when males and females formed temporary consortships for mating purposes. Comparison between several populations revealed an interesting mechanisms for the natural regulation of animal numbers. Differences between Bornean and Sumatran orang-utans are discussed in relation to the zoogeography of these two islands.     

Marking behaviour of the bahaman hutia (Geocapromys ingrahami)

The marking behaviour of a rare hystricomorph rodent, the Bahaman hutia (Geocapromys ingrahami), was studied in captivity. Hutias were more likely to mark urine-scented sticks than to mark unscented controls. The odour of conspecific urine readily induced marking and the sight and/or odour of an animal marking often immediately led to marking by other animals. Marking was exhibited by both males and females regardless of whether females were in oestrus. Olfactory investigation and marking by males was more intense, however, in the presence of oestrous females or their scent. Marking appears to be primarily a non-agonistic, social behaviour which may be important in the social organization of this gregarious, nocturnal species.     

Predatory behaviour of young great kiskadees (Pitangus sulphuratus)

Six hand-reared great kiskadees (Pitangus sulphuratus) were given still and moving models of prey. Series A bore various combinations of eyes, tail, neck and motion; eyes and tail were the most strongly directing. Series B bore various colours and patterns, both as covering the whole model, and as covering only one-third (middle or end). The birds were not inhibited by any plain colour tested but strongly avoided patterns resembling coral snakes. Given sufficient contrast, kiskadees were attracted to the painted section of the partly painted models, regardless of location (middle or end). This attraction to the contrasting section, plus the directed responses to eyes, tail and motion, should allow kiskadees to take small vertebrates like lizards quickly and efficiently.     

Metabolic and ventilatory physiology of the Barrow Island golden bandicoot (Isoodon auratus barrowensis) and the northern brown bandicoot (Isoodon macrourus)

Metabolic and ventilatory parameters were measured for the smallest and largest Isoodon bandicoots; the arid-adapted Barrow Island golden bandicoot (Isoodon auratus barrowensis) and the tropical northern brown bandicoot (Isoodon macrourus). I. a. barrowensis has a number of physiological characteristics that aid its tolerance of high T_a and survival in a hot and dry climate, including a low and labile body temperature, a very low basal metabolic rate, low total evaporative water loss, and an effective panting mechanism. I. macrourus generally has an “average” physiology for a bandicoot despite its size, although a number of its physiological characteristics aid survival in (sub)tropical conditions. These include a low body temperature, low total evaporative water loss and minute ventilation at high ambient temperatures, and an average thermal conductance. These data support the theory that phylogeny is a more important predictor of bandicoot physiology than habitat/distribution.     

Genetics of social behaviour in charrs (Salvelinus species)

Juvenile brook charr (Salvelinus fontinalis) are territorial and have high levels of agonistic behaviour. Juvenile lake charr (S. namaycush) rarely show any indication of territoriality and have very low levels of agonistic behaviour. The inheritance of behaviour in their reciprocal hybrids was investigated by multivariate stepwise discriminant analysis. Lateral display, charge, chase, and forage composed the first canonical axis (87.2% of total dispersion). Pooled hybrid means were closer to that of brook charr, suggesting either directional dominance or modification of the behaviour of hybrids in response to water flow. The mean values of reciprocal hybrids were skewed towards the maternal parent, suggesting a maternal effect in the phenotypic expression of behaviour in these fish.     

Comparative study on the delignification of Azadirachta indica (L) Del., wood by Chrysosporium asperatum and Trichoderma harzianum

Structural alterations induced in response to degradation by two white rot Basidiomycetes on the secondary xylem of Azadirachta indica (L) Del., was compared. In vitro decay test was employed to investigate the pattern of delignification of Azadirachta wood by Trichoderma harzianum and Chrysosporium asperatum. Wood samples inoculated with both the strains were analyzed for different periods viz. 30, 60, 90 and 120 days after fungal inoculation. Initially there was no appreciable percent weight loss of the wood blocks but later on (after 60 days) it increased rapidly and was found similar for both the strains (43-46% of wood mass). Samples inoculated with both the strains showed dual pattern of degradation i.e. selective delignification in the initial stage followed by simultaneous rot during advance stage of decay. Separation of the cells due to dissolution of middle lamella was the characteristic feature of both strains but in the advanced stage of decay, formation of erosion troughs were conspicuous in all the cell types. Other features such as cell wall thinning, rounded pit erosion, formation of erosion channels and bore holes were also observed frequently. Initially, fungal invasion started through the vessel lumen, followed by all the cell types of the xylem. From the vessels, mycelia entered into the adjacent rays and parenchyma cells through the pits. In advanced stage, degradation was so pronounced that rays were partially or even completely destroyed while many cells including vessels were either deformed or destroyed due to loss of rigidity of their walls. Structural alterations induced in response to C. asperatum and T. harzianum attack is described in details.