Predicting Capacity Demand on Sanctuaries for African Chimpanzees (<Emphasis Type="Italic">Pan troglodytes</Emphasis>)

Wildlife sanctuaries rescue, rehabilitate, reintroduce, and provide life-long care for orphaned and injured animals. Understanding a sanctuary’s patterns in arrival, mortality, and projected changes in population size can help managers plan carefully for future needs, as well as illuminate patterns in source populations of wildlife. We studied these dynamics for chimpanzees (Pan troglodytes) in 11 sanctuaries of the Pan African Sanctuary Alliance (PASA). We analyzed historic demographic patterns and projected future population dynamics using an individual-based demographic model. From 2000 to 2006, the population in these sanctuaries has been growing at a rate of 15% per year. This growth is driven by arrivals of new individuals, with an average of 56 arrivals per year. The median age of the 760 chimpanzees living in these sanctuaries as of 2007 was 9 yr, with 76% of the population <15 yr. We found no significant difference in survivorship to age 20 between these chimpanzees and those maintained in North American accredited zoos. The size of the population in 20 yr is projected to be between 550 and 1800, depending on different assumptions about arrival and reintroduction rates. Projected shifts in age structure, including increases in the proportions of adolescent (9–19 yr of age) and older (35+) chimpanzees, may necessitate adjustments to management, veterinary care, and housing. This research illustrates how data on historic population dynamics can be modeled to inform future sanctuary capacity and management needs, allowing sanctuaries to plan better for their populations’ long-term care.     

Coordination of Chimpanzees (<Emphasis Type="Italic">Pan troglodytes</Emphasis>) in a Stag Hunt Game

Group-living animals frequently face situations in which they must coordinate individual and sometimes conflicting goals. We assessed chimpanzees’ ability to coordinate in a Stag Hunt game. Dyads were confronted with a situation in which each individual was already foraging on a low-value food (hare) when a high-value food (stag) appeared that required collaboration for retrieval, with a solo attempt to get the stag resulting in a loss of both options. In one condition visibility between partners was open whereas in the other it was blocked by a barrier. Regardless of condition, dyads almost always (91%) coordinated to choose the higher valued collaborative option. Intentional communication or monitoring of the partner’s behavior before decision making—characteristic of much human coordination—were limited. Instead, all dyads adopted a leader–follower strategy in which one partner took the risk of going first, presumably predicting that this would induce the other to join in (sometimes communicating if she was slow to do so). These results show that humans’ closest primate relatives do not use complex communication to coordinate but most often use a less cognitively complex strategy that achieves the same end.     

The Occurrence of Postconflict Skills in Captive Immature Chimpanzees (<Emphasis Type="Italic">Pan troglodytes</Emphasis>)

Conflict management strategies can reduce costs of aggressive competition in group-living animals. Postconflict behaviors such as reconciliation and third-party postconflict affiliation are widely accepted as social skills in primates and have been demonstrated in many species. Although immature primates possess a repertoire of species-specific behaviors, it is thought that they gradually develop appropriate social skills throughout prolonged juvenility to establish and maintain complex social relationships within their group. We examined the occurrence of postconflict skills in five immature chimpanzees (Pan troglodytes) over 15 mo, focusing on interactions that were not with the subject’s mother. We observed reconciliation, with conciliatory tendencies comparable to adults, and provide the first evidence that captive immature chimpanzees commonly reconciled using social play. However, immatures were not more likely to reconcile valuable than nonvaluable relationships. We also observed third party postconflict affiliation although at a lower level than reported for adults. Our results provide evidence for postconflict skills in immature chimpanzees but the lack of higher conciliatory tendency with valuable partners and low occurrence of third-party affiliation indicates extended juvenility may be required refine these skills. Further work is needed to investigate whether these behaviors have the same function and effectiveness as those found in adults.     

Spatial rotations and transpositions in orangutans (<Emphasis Type="Italic">Pongo pygmaeus</Emphasis>) and chimpanzees (<Emphasis Type="Italic">Pan troglodytes</Emphasis>)

This study investigated the ability of three chimpanzees and three orangutans to track the position of a reward after a series of displacements. The reward was placed under one of two opaque containers resting on a platform. Experiment 1 investigated rotational displacements in which the platform was rotated 0°, 180°, or 360°. Experiment 2 investigated transpositional displacements in which the platform remained stationary while the containers either remained stationary, or swapped their positions (in a one- two- or three-step sequence). In both experiments, the initial position of the reward was indicated either by directly showing the reward under the containers, or by placing a landmark, which had been previously associated with the reward, on top of the baited container. Subjects successfully tracked the reward through rotations and transpositions when they had seen it, but their performance substantially deteriorated when the landmark indicated the reward's initial position, even though subjects successfully used the landmark to find the reward in the absence of displacements. This decrease was especially pronounced in rotational displacements. A language-trained orangutan outperformed all the other apes and solved all problems.     

Chimpanzees (<Emphasis Type="Italic">Pan troglodytes</Emphasis>) learn to act with other individuals in a cooperative task

We presented two chimpanzees with a task in which they were required to pull each end of a rope simultaneously to drag blocks supporting food into reach. The chimpanzees did not succeed in initial tests. They did not immediately understand the necessity for cooperation, and they did not adjust their behavior to work with the partner. However, the frequency of success gradually increased as the number of sessions increased and the task was varied. They began to look at the partner frequently, wait if the partner was not holding the rope, and pull the rope in synchrony with the partner. However, they did not use interactive behaviors or eye contact to synchronize their behavior. One chimpanzee was then paired with a human partner in the same situation. After initial failures, the chimpanzee began to solicit the human partner for cooperation: looking up at his face, vocalizing, and taking the partner’s hand. When this chimpanzee was again paired with the chimpanzee partner, no soliciting behavior was observed. Thus, the chimpanzees could learn to coordinate their behavior through trial and error. Communicative behavior emerged during the task, but the communication differed according to the identity of the partner.     

Linkage of <Emphasis Type="Italic">Patr-AL</Emphasis> to <Emphasis Type="Italic">Patr-A</Emphasis> and-<Emphasis Type="Italic">B</Emphasis> in the major histocompatibility complex of the common chimpanzee (<Emphasis Type="Italic">Pan troglodytes</Emphasis>)

Patr-AL is a recently described gene found only in the common chimpanzee, but closely related in structure to the highly polymorphic Patr-A and HLA-A genes of the chimpanzee and human MHCs, respectively. Unlike Patr-A and HLA-A, the Patr-AL gene has little polymorphism and is not fixed in the chimpanzee genome. To determine whether Patr-AL is located in the MHC or elsewhere, we compared segregation of the Patr-AL gene with segregation of Patr-A and - B alleles in chimpanzee families. The results demonstrate that Patr-AL is an MHC class I gene present on different MHC haplotypes as defined by their combination of Patr-A and B alleles.     

Survey of gorillas (<Emphasis Type="Italic">Gorilla gorilla gorilla</Emphasis>) and chimpanzees (<Emphasis Type="Italic">Pan troglodytes troglodytes</Emphasis>) in Southwestern Cameroon

A study on the distribution and population density of the western lowland gorilla (Gorilla g. gorilla) and the central chimpanzee (Pan t. troglodytes) was undertaken between December 1997 and August 2000 in the Campo and Maan Forests in southwestern Cameroon. The aim of this survey was to estimate the densities of the apes in different parts of the area, to assess the importance of the region for the conservation of these endangered species and to determine the influence of human activities such as logging and hunting. The survey was based on night nest counts on a total of 665.5 km of line transects. The overall density in the Campo Forest was estimated at 0.2 gorillas/km² and at 0.63–0.78 chimpanzees/km². The overall density of chimpanzees in the Maan Forest was estimated at 0.8–1 individuals/km². Gorilla density in this area was too low to allow an estimation. The highest gorilla nest density was found in secondary forest. The gorilla density in unlogged forest was significantly lower. Chimpanzees showed a clear preference for less disturbed areas. In unlogged forest, old secondary forests (logging more than 23 years ago) and areas of recent logging with large remaining patches of primary forest, significantly higher densities were calculated than inside the more heavily exploited logging concession. In areas with both logging and high hunting pressure both species were rare or even absent. The Campo Maan area is considered a very important area for the conservation of gorillas and chimpanzees. Conservation measures are urgently required to reduce the impact of logging and hunting. The creation of the Campo Maan National Park in January 2000 is an important measure to preserve the unique biodiversity in this so far hardly protected area.     

Chimpanzees (<Emphasis Type="Italic">Pan troglodytes</Emphasis>) Flexibly Use Introduced Species for Nesting and Bark Feeding in a Human-Dominated Habitat

As habitat loss and fragmentation place growing pressure on endangered nonhuman primate populations, researchers find increasing evidence for novel responses in behavior. In western Uganda between the Budongo and Bugoma Forests, chimpanzees (Pan troglodytes schweinfurthii) inhabit a mosaic landscape comprising forest fragments, human settlements, and agricultural land. We recorded nests and feeding evidence of unhabituated chimpanzees in this region over a 12-mo period. We found extensive evidence of nesting in introduced tree species, including eucalyptus (Eucalyptus grandis), guava (Psidium guajava), cocoa (Theobroma cacao), and Caribbean pine (Pinus caribaea). In addition, we found instances of ground nesting, nest reuse, and composite nests constructed from branches of multiple trees. This evidence may indicate a lack of suitable nesting trees or attempts by chimpanzees to nest in areas of riparian forest that allow them to avoid human detection. We also found new evidence for eucalyptus bark feeding by chimpanzees. Such evidence suggests chimpanzees respond flexibly to mitigate anthropogenic pressures in human-dominated landscapes. The limits of such flexibility remain unknown. Further research is needed to examine systematically the factors influencing the use of such resources and to understand better the extent to which chimpanzees can persist while relying on them.     

Successful reproduction in wild-released orphan chimpanzees (<Emphasis Type="Italic">Pan troglodytes troglodytes</Emphasis>)

We report a case of successful reproduction in wild-released orphan chimpanzees. Using non-invasive genetic analysis, we determined the paternity of an infant born to a female chimpanzee released by HELP (Habitat Ecologique et Liberté des Primates) Congo into the Conkouati-Douli National Park, Republic of Congo. The sire was a released male, thus demonstrating successful reproduction in both male and female released chimpanzees. These results provide evidence that release into the wild may be a viable response to the plight of orphan chimpanzees in Africa, and we discuss further applications of non-invasive genetic tagging to release programs. Electronic Publication     

A Comparison of Female Mating Strategies in <Emphasis Type="Italic">Pan troglodytes</Emphasis> and <Emphasis Type="Italic">Pongo</Emphasis> spp.

Orangutans and chimpanzees differ in many aspects of their mating and social systems. Nevertheless, because both great apes require enormous maternal investment in offspring and because female reproductive potential is limited, female orangutans and chimpanzees should be selective of their mates, yet expected to exhibit anti-infanticide strategies such as mating with multiple males. We review and compare mating patterns in orangutans and chimpanzees to understand how these critical pressures are filtered through the different demands of the socioecology of each species. We highlight the variation in female mating behavior as a function of the proximity of ovulation. We conclude that both genera pursue tactics for paternity confusion by mating with multiple males and by mating cooperatively or even proceptively with nonpreferred partners when conception is unlikely. Mating selectivity is suggested by variation in proceptive behavior toward particular partners and by increased resistance of nonpreferred partners during the periovulatory period. Thus, data for both species support a mixed mating strategy whereby females shift their mating behavior in accordance with ovulatory status to accommodate the competing demands of mate selectivity and paternity confusion.     

Human Fatality by Escaped <Emphasis Type="Italic">Pan troglodytes</Emphasis> in Sierra Leone

In April 2006, a group of chimpanzees escaped from the Tacugama Chimpanzee Sanctuary in Sierra Leone, resulting in the death of 1 local citizen and injury of another. The chimpanzees caused no further damage after the initial incident. Of the 31 escaped chimpanzees, 27 returned to the sanctuary by the end of 2006, 21 of them voluntarily. The sanctuary is in a forest reserve, a habitat of wild chimpanzees. Ironically, the tragic incident provided an opportunity to observe the behavior of the escaped chimpanzees and their adaptability in the forest. As a result of the incident, local communities could have come to fear the chimpanzees or develop negative feelings toward the sanctuary and its activities, which include keeping a colony of orphaned chimpanzees for rehabilitation and promoting the protection of wild populations. However, collaboration and understanding among the sanctuary, local communities, and government authorities resulted in peaceful handling of the situation and the humane retrieval of 27 of the escaped chimpanzees. As the number of chimpanzees in African sanctuaries increases, they are responsible more than ever for minimizing hazards to surrounding communities. It is important for sanctuaries to develop understanding and to raise support from local communities and government authorities to help them avoid crises and continue their activities.     

Factors Influencing the Survival of Sympatric Gorilla (<Emphasis Type="Italic">Gorilla gorilla gorilla</Emphasis>) and Chimpanzee (<Emphasis Type="Italic">Pan troglodytes troglodytes</Emphasis>) Nests

Accurate and precise surveys of primate abundance provide the basis for understanding species ecology and essential information for conservation assessments. Owing to the elusive nature of wild apes and the vast region of dense forest they inhabit, population estimates of central chimpanzees (Pan troglodytes troglodytes) and western lowland gorillas (Gorilla gorilla gorilla) have largely relied on surveys of their nests. Specific information about the nesting behavior of apes permits the estimation of the number of nests built (nest creation rate). Similarly, information on nest characteristics and environmental factors can be used to estimate the time it takes nests to decay (nest decay rate). Nest creation and decay rates are then used to convert nest density estimates to absolute ape densities. Population estimates that use site-specific estimates of nest creation and decay rates are more accurate and precise. However, it is common practice to generalize these conversion factors across sites because of the additional cost of studies required to gather the information to estimate them. Over a 9-mo study period, we detected and monitored the time to decay of gorilla nests (N = 514) and chimpanzee nests (N = 521) in northern Republic of Congo. We investigated the influence of nest characteristics and environmental factors on nest survivorship and estimated the mean time to nest decay (or equivalently survival) using MARK. Key factors influencing nest decay rate included ape species, forest type, nest height, mean rainfall, nest structure, nest type, and primary aspects of nest construction. Our findings highlight the synergistic effect of behavior and environment on great ape nest degradation, as well as providing practical insights for improving measures to monitor remaining populations of these endangered species.     

Bone Growth Dynamics of the Facial Skeleton and Mandible in <Emphasis Type="Italic">Gorilla gorilla</Emphasis> and <Emphasis Type="Italic">Pan troglodytes</Emphasis>

Adult craniofacial morphology results from complex processes that involve growth by bone modelling and interactions of skeletal components to keep a functional and structural balance. Previous analyses of growth dynamics in humans revealed critical changes during late ontogeny explaining particular morphological features in our species. Data on bone modelling patterns from other primate species could help us to determine whether postnatal changes in the growth dynamics of the craniofacial complex are human specific or are shared with other primates. However, characterizations of bone modelling patterns through ontogeny in non-human hominids are scarce and restricted to isolated data on facial and mandibular regions. In the present study, we analyse the bone modelling patterns in an ontogenetic series of Pan and Gorilla to infer the growth dynamics of their craniofacial complex during postnatal development. Our results show that both Pan troglodytes and Gorilla gorilla are characterized by species-specific bone modelling patterns indicative of a mainly forward growth direction during postnatal development. Both species show minor but consistent ontogenetic changes in the distribution of bone modelling fields in specific regions of the face and mandible, in contrast to other regions which show more constant bone modelling patterns. In addition, we carry out a preliminary integrative study merging histological and geometric morphometric data. Both approaches yield highly complementary data, each analysis providing details on specific growth dynamics unavailable to the other. Moreover, geometric morphometric data show that ontogenetic variation in the modelling pattern of the mandibular ramus may be linked to sexual dimorphism.     

Reproductive Parameters of Female<Emphasis Type="Italic">Pan paniscus</Emphasis> and <Emphasis Type="Italic">P. troglodytes</Emphasis>: Quality versus Quantity

We investigated intra- and interspecific differences in life history and reproductive parameters in bonobos (Pan paniscus) and chimpanzees (Pan troglodytes). We compare the parameters of wild and captive females in order to shed light on the influence of habitat or specific differences or both on reproduction. We present new and additional information on reproductive parameters from captive bonobos and chimpanzees. Captive chimpanzees birth more live offspring and have a shorter interbirth interval, but experience higher infant mortality than captive bonobos. Although captive bonobo females tend to start reproduction at a younger age than chimpanzees, this is effectively only so for wild-born females of both species. Ultimately both species reach the same rate of production of offspring surviving to 5 yr. These results contrast with data from the wild. Wild bonobos tend to have higher reproductive success, a higher fertility rate and a shorter interbirth interval than wild chimpanzees. Reproduction is similar for wild and captive bonobos, which suggests that they are producing at their maximum under both conditions. Overall captive chimpanzees perform better than their wild conspecifics, probably because of lower feeding competition. Infant survival is the only specific difference not affected by captivity. Bonobo infants survive better, which suggests that chimpanzee infants are more at risk. We argue that the interspecific variation in reproductive parameters in captivity is related to the different influence of captivity on reproduction and different pressures of external sources of infant and juvenile mortality.     

New combinations and typifications in <Emphasis Type="Italic">Bistorta</Emphasis>, <Emphasis Type="Italic">Persicaria</Emphasis>, <Emphasis Type="Italic">Polygonum,</Emphasis> and <Emphasis Type="Italic">Rumex</Emphasis> (Polygonaceae)

New combinations are proposed in anticipation of the Polygonaceae treatment in the forthcoming volume of Intermountain Flora: Polygonum kelloggii var. esotericum, P. kelloggii var. watsonii , Rumex densiflorus var. pycnanthus , R. salicifolius var. utahensis, and R. occidentalis var. tomentellus. Typifications are proposed to facilitate ongoing studies in Polygonaceae and to maintain current usage.     

<Emphasis Type="Italic">Ty</Emphasis>1<Emphasis Type="Italic">/copia</Emphasis>- and <Emphasis Type="Italic">Ty</Emphasis>3<Emphasis Type="Italic">/gypsy</Emphasis>-like DNA sequences in <Emphasis Type="Italic">Helianthus </Emphasis>species

Two repeated DNA sequences isolated from a partial genomic DNA library of Helianthus annuus, p HaS13 and p HaS211, were shown to represent portions of the int gene of a Ty3 /gypsy retroelement and of the RNase-Hgene of a Ty1 /copia retroelement, respectively. Southern blotting patterns obtained by hybridizing the two probes to BglII- or DraI-digested genomic DNA from different Helianthus species showed p HaS13 and p HaS211 were parts of dispersed repeats at least 8 and 7 kb in length, respectively, that were conserved in all species studied. Comparable hybridization patterns were obtained in all species with p HaS13. By contrast, the patterns obtained by hybridizing p HaS211 clearly differentiated annual species from perennials. The frequencies of p HaS13- and p HaS211-related sequences in different species were 4.3x10(4)-1.3x10(5) copies and 9.9x10(2)-8.1x10(3) copies per picogram of DNA, respectively. The frequency of p HaS13-related sequences varied widely within annual species, while no significant difference was observed among perennial species. Conversely, the frequency variation of p HaS211-related sequences was as large within annual species as within perennials. Sequences of both families were found to be dispersed along the length of all chromosomes in all species studied. However, Ty3 /gypsy-like sequences were localized preferentially at the centromeric regions, whereas Ty1/ copia-like sequences were less represented or absent around the centromeres and plentiful at the chromosome ends. These findings suggest that the two sequence families played a role in Helianthusgenome evolution and species divergence, evolved independently in the same genomic backgrounds and in annual or perennial species, and acquired different possible functions in the host genomes.     

Behavioral evidence of color vision deficiency in a protanomalia chimpanzee (<Emphasis Type="Italic">Pan troglodytes</Emphasis>)

Although color vision deficiency is very rare among Old World monkeys and apes, one male chimpanzee (Lucky) was identified as protanomalous by genetic and physiological analyses. This study assessed behavioral phenotypes of Lucky and four chimpanzees with normal color vision by discrimination task using the modified Ishihara pseudo-isochromatic plates. Lucky could not discriminate the stimuli that the other chimpanzees could. This is the first behavioral evidence of color vision deficiency in chimpanzees. Electronic Publication     

Floral development and systematic position of <Emphasis Type="Italic">Arillastrum</Emphasis>, <Emphasis Type="Italic">Allosyncarpia</Emphasis>, <Emphasis Type="Italic">Stockwellia</Emphasis> and <Emphasis Type="Italic">Eucalyptopsis</Emphasis> (Myrtaceae)

We have investigated the floral ontogeny of Arillastrum, Allosyncarpia, Stockwellia and Eucalyptopsis (of the eucalypt group, Myrtaceae) using scanning electron microscopy and light microscopy. Several critical characters for establishing relationships between these genera and to the eucalypts have been determined. The absence of compound petaline primordia in Arillastrum, Allosyncarpia, Stockwellia and Eucalyptopsis excludes these taxa from the eucalypt clade. Post-anthesis circumscissile abscission of the hypanthium above the ovary in Stockwellia, Eucalyptopsis and Allosyncarpia is evidence that these three taxa form a monophyletic group; undifferentiated perianth parts and elongated fusiform buds are characters that unite Stockwellia and Eucalyptopsis as sister taxa. No floral characters clearly associate Arillastrum with either the eucalypt clade or the clade of Stockwellia, Eucalyptopsis and Allosyncarpia.We gratefully acknowledge Clyde Dunlop and Bob Harwood (Northern Territory Herbarium) for collecting specimens of Allosyncarpia, and Bruce Gray (Atherton) for collecting specimens of Stockwellia. The Australian National Herbarium (CANB) kindly lent herbarium specimens of Eucalyptopsis for examination. This research was supported by a University of Melbourne Research Development Grant to Andrew Drinnan.     

<Emphasis Type="Italic">In silico</Emphasis> and <Emphasis Type="Italic">in situ</Emphasis> characterization of the zebrafish (<Emphasis Type="Italic">Danio rerio</Emphasis>) <Emphasis Type="Italic">gnrh3</Emphasis> (sGnRH) gene

Background

Gonadotropin releasing hormone (GnRH) is responsible for stimulation of gonadotropic hormone (GtH) in the hypothalamus-pituitary-gonadal axis (HPG). The regulatory mechanisms responsible for brain specificity make the promoter attractive for in silico analysis and reporter gene studies in zebrafish (Danio rerio).

Results

We have characterized a zebrafish [Trp⁷, Leu⁸] or salmon (s) GnRH variant, gnrh 3. The gene includes a 1.6 Kb upstream regulatory region and displays the conserved structure of 4 exons and 3 introns, as seen in other species. An in silico defined enhancer at -976 in the zebrafish promoter, containing adjacent binding sites for Oct-1, CREB and Sp1, was predicted in 2 mammalian and 5 teleost GnRH promoters. Reporter gene studies confirmed the importance of this enhancer for cell specific expression in zebrafish. Interestingly the promoter of human GnRH-I, known as mammalian GnRH (mGnRH), was shown capable of driving cell specific reporter gene expression in transgenic zebrafish.

Conclusions

The characterized zebrafish Gnrh3 decapeptide exhibits complete homology to the Atlantic salmon (Salmo salar) GnRH-III variant. In silico analysis of mammalian and teleost GnRH promoters revealed a conserved enhancer possessing binding sites for Oct-1, CREB and Sp1. Transgenic and transient reporter gene expression in zebrafish larvae, confirmed the importance of the in silico defined zebrafish enhancer at -976. The capability of the human GnRH-I promoter of directing cell specific reporter gene expression in zebrafish supports orthology between GnRH-I and GnRH-III.

     

Pedogamy in <Emphasis Type="Italic">Neidium</Emphasis> (<Emphasis Type="Italic">Bacillariophyceae</Emphasis>)

Single (unpaired) vegetative cells of freshwater pennate diatom Neidium cf. ampliatum differentiated into gametangia and produced a single zygote (auxospore) via a pedogamic process. The gametic nuclei fused after auxospore expansion had begun. The auxospore expanded in parallel to the apical axis of the gametangium.