Whether treatment programs are effective at rehabilitating rapists is yet to be determined empirically. From a scientist-practitioner perspective, treatment should be based on an empirical understanding of rape and rapists, and evidence-based knowledge of treatment outcome with rapists. In this paper we comprehensively review the characteristics of rapists, etiological features implicated in the commission of rape, and relevant treatment outcome research. We pay particular attention to contemporary knowledge about the core vulnerabilities and features required to understand and treat rapists effectively, and, where possible, highlight similarities and differences between rapists, child molesters and non-sexual violent offenders. We use an epistemological framework to (a) critique the various etiological accounts of rape available and (b) help guide professionals' use of such knowledge in both treatment design and evaluation. Gaps in the understanding of rapists' characteristics and etiological features are highlighted, as are discrepancies between current knowledge and treatment approaches. We conclude by highlighting areas for future research and practice innovation.

This study examined the locomotor behavior of wild Bornean orangutans (P. p. wurmbii) in an area of disturbed peat swamp forest (Sabangau Catchment, Indonesia) in relation to the height in the canopy, age-sex class, behavior (feeding or traveling), and the number of supports used to bear body mass. Backward elimination log-linear modeling was employed to expose the main influences on orangutan locomotion. Our results showed that the most important distinctions with regard to locomotion were between suspensory and compressive, or, orthograde (vertical trunk) and pronograde (horizontal trunk) behavior. Whether orangutans were traveling or feeding had the most important influence on locomotion whereby compressive locomotion had a strong association with feeding, suspensory locomotion had a strong association with travel in the peripheral strata using multiple supports, whereas vertical climb/descent and oscillation showed a strong association with travel on single supports in the core stratum. In contrast to theoretical predictions on positional behavior and body size, age-sex category had a limited influence on locomotion. The study revealed that torso orthograde suspension dominates orangutan locomotion, concurring with previous studies in dipterocarp forest. But, orangutans in the Sabangau exhibited substantially higher frequencies of oscillatory locomotion than observed at other sites, suggesting this behavior confers particular benefits for traversing the highly compliant arboreal environment typical of disturbed peat swamp forest. In addition, torso pronograde suspensory locomotion was observed at much lower levels than in the Sumatran species. Together these results highlight the necessity for further examination of differences between species, which control for habitat.

This report summarizes a variety of research findings and tips from web designers on how to make web sites more appealing, educational and entertaining for children. Given the great importance of computers and Internet technology in children’s lives, web sites that appeal to tweens (pre-teenaged children usually between the ages of nine and twelve) are in great demand. To design web sites that are appropriate for, and appeal to children, designers must understand the characteristics that make children different than adult web users and use specific design strategies that will facilitate a functional and appealing design based on the preferences and needs of the target audience. Factors that motivate children's online activities Self-expression Whether creating web pages, content, or new identities, the expression of self is an important reason for kids to come to online venues. Kids are avid communicators in the online world, often creating characters or “handles” that express real or fantasy element of themselves. Additionally, kids often like sites where they can “leave a footprint”, or impression of their presence. They enjoy venting frustrations, writing fan letters, expressing ideas to their peers and site experts, or even designing their own areas, pages, or worlds. (Bruckman, 1997; Sullivan, Norris, Soloway & Peet, 2000; Wartella, O'Keefe & Scantlin, 2000) Social Relationships A primary use of online media is the capacity to enrich, reinforce, and even create social relationships with peers. (Bruckman, 1997; Fishler, 1998) Interestingly, this phenomenon may be stronger for boys than for girls. Boys report that playing games online is a compelling social activity that they engage in with playmates. They use gaming in a social context as an integral part of conversation, comparing scores, strategies and progress. Additionally, boys that game together are more likely to play together, or visit each other’s homes. (Wartella, O'Keefe & Scantlin, 2000) Though females are not as likely to use online interactions to strengthen existing relationships, females do engage in online communication that is social in nature. Females are much less likely to play networked games together, but they are much more likely to use electronic mail, instant messaging, “buddy lists” and other technological innovations as tools to broaden the network of personal communication beyond the realm of family and close friends. (Makela, Giller Tscheligi & Sefelin, 2000; Sullivan, Norris, Soloway & Peet, 2000; Wartella, O'Keefe & Scantlin, 2000) Social Identity Formation As kids approach adolescence, the concept of group membership as a definition of self becomes more and more prevalent. In the real world they are contending with cliques, and labels and in the virtual world they can reinforce or transcend these practices. For boys, gaming can result in groups that train and play together, and even the games that they play help them define the groups that they are part of. For all children, the anonymity of the web can be a great place to pair up based on interests. Kids group together based on traits that may not be salient for friendship formation if they met in the real world. For example, in one study of a children’s MOO (a more socially-oriented version of an online world that evolved from MUDs that were created for online role playing games), users that were brainy befriended the popular kids, a situation that probably would not have happened had the kids met face-to-face. (Bruckman, 1997; Sullivan, Norris, Soloway & Peet, 2000) Additional Gender Differences There are slight gender differences in media usage, and this differentiation in media usage widens with age. (Beatto, 1997; Bernard, 2001; Howard, 1998) Though boys and girls spend approximately the same amount of time using media each day, girls are apt to listen to more music. Boys generally watch more television and play more video games than girls. Boys in the 2-7 year old age group use an average of 19 minutes more media a day than girls in the same age group. By the time children reach the tweens, the gap has widened to a 24-minute difference. The types of media preferred differ by gender as well. Research findings show that girls are comfortable on the Internet, in fact some studies have shown that girls use the Internet more than boys. While spending roughly the same amount of time, the types of activities that boys and girls engage in online are somewhat different. Girls are more likely to use the Internet for education, schoolwork, email and chat rooms while boys are more likely to use the Internet for entertainment and games. (NSBF, 2000) Generally speaking boys tend to spend more time playing games than girls, and there are differences in the types of games that boys and girls play. Boys generally preferring sports, action adventure and violent action games, while girls generally prefer educational, puzzle, spatial relation and fantasy-adventure games. (Berselli, 1998) Generalizations of the differences between genders are summarized below. GIRLS ONLINE BOYS ONLINE When online, girls tend to engage in activities that are educational or communicative in nature. Schoolwork, email and chatting are common uses; other activities include music and shopping. (NSBF, 2000) Girls use technology to share, create and express themselves. (Bruner, Bennet & Honey, 1998) Boys use Internet and computer technology primarily for entertainment and recreation purposes and as a way to exert control and power or to express their autonomy. Games are the primary activity of most boys online. (NSBF, 2000) Reasons for their interest in games include a sense of challenge, competition, complexity, reward and stimulation. Design Tips for Designers creating Web Sites for Children Seek Feedback from kids during the design process The golden rule for designing web sites for kids is to seek input and feedback from children throughout the design process. Children are fundamentally different than adults and can have profoundly different responses to media content. According to KimWimpsett, a web designer and author of a series of articles on web design for cNET, "Children think and learn differently than adults do, and the Web sites they like are different too. Basic Web design principles still apply—keep pages fast and lean, for example-but kidoriented Web builders face unique issues when designing sites specifically for a young audience." (Wimpsett, 1998) It is also important to consider the fact that today's youth may be inherently different than previous generations. Children today have had access to different media and have experienced different world events than those that helped to mold and shape their predecessors. According to Donald Tapscott, "The changing nature of childhood makes itself most obvious when N-Geners are contrasted with the baby boomers who, as a generation, have spent their lives obsessed with being youthful. N-Geners insist that they are more mature than adults expect." (Tapscott, 1998) By way of the Internet and new media children today have access to much of the world's knowledge, millions of other children, and countless places and sites to explore at their fingertips—things that were virtually unimaginable by children growing up without the Internet. Adults will sometimes design products for kids with the assumption that we they know what is best for them. Where interactive design for children is concerned children sometimes know best, and it’s important for adults to feel comfortable handing them the reigns from time to time. (Druin, 1999) The only real authorities on what makes a site appealing to children are children themselves. Richly mediated environments offer an appeal for children Kids enjoy being immersed in richly mediated environments. It is important to take advantage of what the web has to offer in terms of design options—being web-imaginative in our designs ensures that the full potential of the Internet is realized. Thinking beyond flashy graphics and images can also be of benefit when designing for kids. Research shows that kids prefer and learn better with a rich combination of text, graphics, sound and animation. (Harel, 2001) Having arrived as a true multimedia medium, the web allows designers the opportunity to include sound and animated content as well as text and static images. Bright and bold visual elements, especially things that move, are favorites among children. (Bruckman, in press) "Where adults might be satisfied with an informative page of plain text, kids need more in order for them to stick around. Good content is very important, but it’s just not enough to simply offer information. That information must be delivered in an interesting way." (Andrea Mulder as quoted in Wimpsett, 1998) As a counter point to the belief that a flashier site is, by default, better than one less flashy, researchers at the Department of Technology and Cognition at the University of Texas have conducted research on children's preference for different types of web sites. So far their research has yet to support the fact that sites with visually rich graphical presentation increase site traffic. (Sullivan, Norris, Soloway & Peet, 2000) Past research has suggested that sites aimed at adults should avoid unnecessary graphics or animations while sites for kids offer more room for the addition of these features. (Wimpsett, 1998) While the verdict is still out on whether or not this is true, initial research has shown that children, not unlike adults, can also find web animations to be distracting and desire to remove them from their visual field. (Sullivan, Norris, Soloway & Peet, 2000) Appropriate use of animation can be beneficial Animation, when used appropriately, can be a valuable tool for designers building web pages for kids. Animation is not the complete solution for providing a fun and engaging experience for kids, but it may be a good place to start. In addit

The behavioral development of young apes is influenced by their physical and social environments. Deficient or limited environments can result in reproductive insufficiencies (see Beck and Power, 1988) and behavioral deficits, such as Stereotypic movements (see Puleo, et al., 1983; Meder, 1989). The role of the environment in behavioral deficits is evident from studies where stereotypies were reduced or eliminated when the physical or social environments were enhanced (Clarke, et al., 1982; Puleo, et al., 1983; Meder, 1989). The mere presence of conspecifics, however, does not guarantee the development of species-typical behavior, even in complex social groups. For example, a young orangutan reared in a social group containing only adults is limited in its opportunities for social play (Zucker, et al., 1986; see Baldwin, 1986, for more about social and ecological constraints on play). Although adult orangutans of both sexes do play, the rate of adult play is much lower than that of immature orangutans (Zucker, et al., 1986), and in playing with immature orangutans, the style of play of adult females differs from that of adult males (Zucker, et al., 1978). Nursery-reared apes are at risk for behavioral deficits as their social and physical environments usually are less complex than their respective natural environments, although nursery environments and rearing protocols can be made relatively complex and stimulating.

The Asian apes, orangutans and gibbons, possess unusual social systems among anthropoid primates. Social groups of gibbons consist of mated adult pairs and their offspring; mature orangutans are primarily solitary. Recent experimental field research has begun to yield insights into the behavioral mechanisms employed by these animals to maintain their characteristic patterns of social dispersion. While spatial separation between female orangutans appears to be maintained passively, aggression, which is manifest during direct encounters and long-distance vocal interactions, mediates male asociality. Male-male aggression is the result of intense intrasexual competition occurring between animals for mating access to females. To reduce intrasexual competition, male orangutans have adopted alternative mating tactics. In contrast to female orangutans, female gibbons show marked agonistic tendencies toward conspecifics. Female territoriality contributes to preventing males from becoming polygynous. Male gibbons, restricted to monogamous relationships, attempt to ensure their paternity through intrasexual aggression. These observations suggest that the spatial dispersion of females constrains male mating options in both species. However, variations between orangutan and gibbon social systems can be understood as consequences of the temporal dispersion of sexually receptive females. The temporal clumping of females, due to relatively high operational sex ratios, limits the ability of male gibbons to acquire multiple mates. Conversely, an extremely low operational sex ratio in orangutans creates a strong selection pressure for intrasexual competition and polygamous mating. These considerations provide a novel framework for interpreting the social systems of the African apes.

Recent research suggests profound sex and sexual orientation differences in sexual response. These results, however, are based on measures of genital arousal, which have potential limitations such as volunteer bias and differential measures for the sexes. The present study introduces a measure less affected by these limitations. We assessed the pupil dilation of 325 men and women of various sexual orientations to male and female erotic stimuli. Results supported hypotheses. In general, self-reported sexual orientation corresponded with pupil dilation to men and women. Among men, substantial dilation to both sexes was most common in bisexual-identified men. In contrast, among women, substantial dilation to both sexes was most common in heterosexual-identified women. Possible reasons for these differences are discussed. Because the measure of pupil dilation is less invasive than previous measures of sexual response, it allows for studying diverse age and cultural populations, usually not included in sexuality research.

Orangutans are the only great apes found outside of Africa. At present, they occur only on the two large Sunda‐shelf islands of Sumatra and Borneo. Most researchers recognize two separate subspecies, Pongo pygmaeus abelii in Sumatra and P.p. pygmaeus in Borneo.1,2 Relative to other primates, they have a variety of unusual features. These large‐bodied frugivores are among the most solitary of anthropoid primates.3–5 They are also highly dimorphic, with the average body mass (78 kg) of males being more than twice that of females (36 kg).6 Despite its large body size the red ape has more specialized morphological adaptations for arboreality than do the African great apes. Researchers generally recognize sexually mature male orangutans with two physically distinct morphs, a phenomenon described as bimaturism. Males of the relatively smaller morph are known for forcing copulations with adult females.5,7–9.

Intersexual conflicts over mating can engender antagonistic coevolution of strategies, such as coercion by males and selective resistance by females. Orangutans are exceptional among mammals for their high levels of forced copulation. This has typically been viewed as an alternative mating tactic used by the competitively disadvantaged unflanged male morph, with little understanding of how female strategies may have shaped and responded to this behaviour. Here, we show that male morph is not by itself a good predictor of mating dynamics in wild Bornean orangutans but that female conception risk mediated the occurrence and quality of male–female interactions. Near ovulation, females mated cooperatively only with prime flanged males who they encountered at higher rates. When conception risk was low, willingness to associate and mate with non-prime males increased. Our results support the hypothesis that, together with concealed ovulation, facultative association is a mechanism of female choice in a species in which females can rarely avoid coercive mating attempts. Female resistance, which reduced copulation time, may provide an additional mechanism for mate selection. However, coercive factors were also important as prime males were frequently aggressive to females and females used mating strategies consistent with infanticide avoidance.

During a four‐year period, more than 6,800 hours of observation were collected on 58 individually recognized wild orangutans in a 35‐km2 study area at the Tanjung Puting Reserve, Kalimantan Tengah (Central Indonesian Borneo). As in other areas, although small temporary associations of orangutans recurred, the basic units of populations consisted of (1) adult males, (2) adult females with one or two dependent offspring, and (3) independent immatures (adolescent males and females and subadult males) with units predominantly solitary. However, independent immatures were more gregarious and social than adults. Adolescent females in particular spent more time in groupings than did adult females. Although successfully consorting adult males might spend up to 22% of time observed in association with other orangutans, adult males were the least social of all age/sex classes once consortships were excluded. Ninety percent of their participation in social groupings consisted of sexual consortships. Adult males were totally intolerant of each other; only four encounters between adult males were observed. All involved avoidance or aggression, including one lengthy combat. Adult females were solitary but social and participated in a variety of groupings. However, with the exception of adult females briefly following consorting couples, nonreceptive adult females did not initiate or maintain social contact with orangutans other than adult females. Comparisons with results of studies from other areas indicate that, once samples used in each study are made explicit and aggregations owing to chance encounters at major food sources excluded, orangutan sociality seems relatively consistent over the entire range in which the species is found. Bornean orangutans are not as totally asocial as the first studies in the wild indicated. In fact, it would probably be better to characterize wild orangutans as semisolitary, rather than solitary.

Data on the presence of wild orang-utans, Pongo pygmaeus, in the Ketambe area (Sumatera, Indonesia), collected over 12 consecutive years, were analysed to study population structure and residential status. Forty-three individuals could be identified during the study period. The socionomic sex ratio was close to unity, at least when subadault and adult males were considered as one category. The adult sex ratio was skewed towards females. A clear distinction between residents and non-residents could be made, but there was apparently no transient sex and no positive correlation between the densities of non-resident males and local females capable of conceiving. Hence, the hypothesis that non-resident males wander to locate receptive females was not supported. Instead, the data reveal seasonal movements and show that non-residents of both sexes are equally attracted to the study area when food is abundant. Two (not mutually exclusive) mechanisms that may explain how ranging of non-residents is tuned to food available are proposed.

Comparative studies of birth interval dynamics in wild primates suffer from several problems of analysis and interpretation: (1) the data are always right-censored, (2) sample sizes are usually small, (3) the distribution of birth intervals is expected to be non-normal, (4) early offspring mortality is a confounding variable, and (5) differences in life history (e.g., presence or absence of menopause) can complicate interpretation of the results. A survival analysis designed to minimize these problems is applied to published data on wild chimpanzees and gorillas from Gombe and Virunga Parks, respectively, and to new data on wild orangutans from Tanjung Puting National Park and on a human population, the Gainj of highland Papua New Guinea. According to this analysis, the estimated median birth interval (when the offspring whose birth opens the interval does not die within the interval) is 43.3 +/- 1.0 months for the Gainj, 45.5 +/- 1.2 months for gorillas, 66.6 +/- 1.3 months for chimpanzees, and 92.6 +/- 2.4 months for orangutans.

Both in the wild and in captivity, a marked and enduring arrest of secondary sexual developmental occurs in some male orangutans (Pongo pygmaeus) (Kingsley [1982] The Orang-Utan: Its Biology and Conservation, The Hague: Junk; Utami [2000]). Researchers have hypothesized that chronic stress, perhaps related to aggression from mature males, causes endocrine changes altering growth and maturation rates in these males (Maple [1980] Orangutan Behavior, New York: Van Nostrand Reinhold; Graham [1988] Orangutan Biology, Oxford: Oxford University Press). In this study, urine samples were collected over a 3-year period from 23 captive male orangutans to test the hypothesis that developmentally arrested male orangutans have an endocrine profile consistent with chronic stress. Three study males were juveniles, seven were arrested adolescents, six were developing adolescents, and seven were mature adults. Morning samples were analyzed by radioimmunoassay for levels of the stress hormones cortisol and prolactin, and group hormone profiles were compared by analysis of variance. Results indicate that developing adolescent male orangutans have a significantly higher stress hormone profile than juvenile, developmentally arrested adolescent, or adult males. These results imply that the arrest of secondary sexual development in some male orangutans is not stress-induced, but instead perhaps an adaptation for stress avoidance during the adolescent or "subadult" period. These data, together with previously reported data on levels of gonadotropins, testicular steroids, and growth-related hormones, define endocrine profiles associated with alternative reproductive strategies for males with and males without secondary sexual features (Maggioncalda et al. [1999], [2000].

Behavioural observations suggest that orang‐utans are semi‐solitary animals with females being philopatric and males roaming more widely in search of receptive partners, leading to the prediction that females are more closely related than males at any given site. In contrast, our study presents evidence for male and female philopatry in the orang‐utan. We examined patterns of relatedness and parentage in a wild orang‐utan population in Borneo using noninvasively collected DNA samples from animals observed to defecate, and microsatellite markers to assess dispersal and mating strategies. Surprisingly, resident females were equally as related to other resident females (mean rxy = 0.303) as resident males were to other resident males (mean rxy = 0.305). Moreover, resident females were more related to each other and to the resident males than they were to nonresident females, and resident males were more related to each other (and resident females) than they were to nonresident males. We assigned genetic mothers to 12 individuals in the population, while sires could be identified for eight. Both flanged males and unflanged males achieved paternity, similar to findings reported for Sumatran orang‐utans.

At first sight, the orangutan may well be the least spectacular of the great apes. In comparison with its African cousins, this solitary creature seems to lead a far less exciting life. Superficially, its social organization is exceptional in comparison with that of other diurnal primates. It is precisely this exceptional characteristic which makes the red ape an interesting test case for socio-ecological theorizing.

At Tanjung Puting, adolescent female orangutans were the most social of all age/sex classes and should not be described as solitary or even semi-solitary. Non-exclusive groupings involving adolescent females and subadult males were the associations most commonly seen at Tanjung Puting. Adolescent female interactions with adult males were almost totally restricted to consortships which the female initiated, maintained, and terminated. Adolescent female interactions with adult females were largely absent due to adult female agonism. This agonism probably relates to child-care constraints and food competition experienced by the adult female. Adolescent female interactions with subadult males involved long term associations in which no copulations took place and short term (<1 day) association in which “resisted mating” occurred. Overall, heterosexual associations were social. Adolescent females did not consort with subadult males. Adolescent female interactions with their own age/sex class were invariably social, and adolescent females always traveled together following encounters. Adolescent females were the only age/sex class observed to carry out interunit grooming. First parturition for wild orangutan females is estimated at approximately 14 or 15 years of age. Adolescent females experience a period of sterility which may exceed one year prior to first parturition. Adolescent females copulate at higher rates than do adult females. Adolescent females were the only age/sex class at Tanjung Puting to display high levels of proceptive behavior. This proceptive behavior, while not always successful, appeared crucial to inducing consorts to copulate. Adolescent females preferred adult males as sexual partners, but themselves were not preferred by adult males. A large amount of learning appears to take place during the orangutan’s adolescence as a result of increased sociality. Due to their small size, rapid travel and long day ranges, sociality probably is not as costly for adolescent female orangutans as it is for adults. Adolescent females probably benefit from associating with other orangutan units because, based on the age/sex class they are associating with, grouping provides: a) a potential context in which to learn adaptive solutions to social and/or environmental problems, b) increased foraging efficiency, c) protection from predators and/or “enemies,” and d) a potential context in which dominance and affiliative relations between individuals can be developed.

Although orang-utans live solitary lives most of the time, they have a complex social structure and are characterized by extreme sexual dimorphism. However, whereas some adult male orang-utans develop full secondary sexual characteristics, such as cheek flanges, others may stay in an "arrested" unflanged condition for up to 20 years after reaching sexual maturity. The result is a marked bimaturism among adult males. Flanged males allow females to overlap with their home range and often tolerate the presence of unflanged males. However, wherever possible flanged males actively prevent unflanged males from copulating with females. Two competing hypotheses, previously untested, have been advanced to explain male reproductive behavior and bimaturism in orang-utans: (1) the "range-guardian" hypothesis, which asserts that the flanged males are postreproductive and defend a range in which they tolerate sexually active, unflanged male relatives; and (2) the "female choice" hypothesis, which asserts that flanged males tolerate unflanged males in their range because they rely on female preference to favor flanged males. We investigated these hypotheses and a third hypothesis that the two male morphs represent co-existing alternative male reproductive strategies ("sitting, calling, and waiting" for flanged males versus "going, searching, and finding" for unflanged males). Fecal samples were collected from a well-studied population in Indonesia, and eight human microsatellites were analyzed for 30 individuals that have been behaviorally monitored for up to 27 years. By carrying out paternity analysis on 11 offspring born over 15 years, we found that unflanged males fathered about half (6) of the offspring. Relatedness between successful unflanged males and resident dominant males was significantly lower than 0.5, and for some unflanged/flanged male pairs, relatedness values were negative, indicating that unflanged males are not offspring of the flanged males. Copyright 2002.

Abstract Striking secondary sexual traits, such as brightly colored “sexual skin,” capes of hair, beards, and other facial adornments occur in adult males of many anthropoid primate species. This review focuses upon the role of sexual selection in the evolution of these traits. A quantitative approach is used to measure sexually dimorphic characters and to compare their development in the monogamous, polygynous, and multimale-multifemale mating systems of monkeys, apes, and human beings.