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Studies of hybrid zones can inform our understanding of reproductive isolation and speciation. Two species of brown lemur (Eulemur rufifrons and E. cinereiceps) form an apparently stable hybrid zone in the Andringitra region of south-eastern Madagascar. The aim of this study was to identify factors that contribute to this stability. We sampled animals at 11 sites along a 90-km transect through the hybrid zone and examined variation in 26 microsatellites, the D-loop region of mitochondrial DNA, six pelage and nine morphological traits; we also included samples collected in more distant allopatric sites. Clines in these traits were noncoincident, and there was no increase in either inbreeding coefficients or linkage disequilibrium at the centre of the zone. These results could suggest that the hybrid zone is maintained by weak selection against hybrids, conforming to either the tension zone or geographical selection-gradient model. However, a closer examination of clines in pelage and microsatellites indicates that these clines are not sigmoid or stepped in shape but instead plateau at their centre. Sites within the hybrid zone also occur in a distinct habitat, characterized by greater seasonality in precipitation and lower seasonality in temperature. Together, these findings suggest that the hybrid zone may follow the bounded superiority model, with exogenous selection favouring hybrids within the transitional zone. These findings are noteworthy, as examples supporting the bounded superiority model are rare and may indicate a process of ecologically driven speciation without geographical isolation.

Thornicroft's giraffe, Giraffa camelopardalis thornicrofti, is a geographically isolated subspecies of giraffe found only in north-east Zambia. The population only occurs in Zambia's South Luangwa Valley, an area which interestingly places it between the current distribution of Masai (G.c.tippelskirchi) giraffe to the north, and the Angolan (G.c.angolensis) and South African (G.c.giraffa) giraffe in the south-west and south, respectively. Specific studies have been undertaken on the ecology of this subspecies, but their population genetics remains unknown. We studied 34 individuals from the South Luangwa National Park and adjacent Lupande Game Management Area and seven individuals from northern Botswana. The complete cytochrome b and control region sequences of the mitochondrial genome were sequenced and analysed together with database data by maximum likelihood tree reconstruction and maximum parsimony network analyses. The giraffe from Zambia's South Luangwa Valley are most closely related to the subspecies G.c.tippelskirchi and part of their radiation. However, they form a unique population that would benefit from increased research and conservation management. Resume La girafe de Thornicroft, Giraffa camelopardalis thornicrofti, est une sous-espece isolee geographiquement que l'on ne trouve qu'au nord-est de la Zambie. Cette population ne vit que dans le sud zambien de la Vallee de la Luangwa, une zone qui la situe entre la distribution actuelle de la girafe masai (G.c.tippelskirchi) au nord, celle de la girafe d'Angola (G.c.angolensis) et celle d'Afrique du Sud (G.c.giraffa), respectivement au sud-ouest et au sud. Des etudes specifiques ont ete entreprises sur l'ecologie de cette sous-espece, mais la genetique de cette population reste inconnue. Nous avons etudie 34 individus du Parc National de South Luangwa et de l'Aire de gestion de la faune de Lupande qui lui est proche et sept individus du nord du Botswana. Les sequences completes du cytochromeb et d'une region de reference du genome mitochondrial ont ete realisees et analysees en regard des donnees de reference par des analyses par reconstruction de l'arbre selon le principe du maximum de vraisemblance et par la methode de parcimonie maximale. Les girafes de la Vallee de South Luangwa en Zambie sont plus etroitement apparentees a la sous-espece G.c.tippelskirchi et font partie de leur radiation. Cependant, elles constituent une population unique qui aurait tout interet a faire l'objet de nouvelles recherches et d'une meilleure gestion de conservation.

To assess genetic diversity in North American captive Asian elephants Elephas maximus, one mitochondrial DNA (mtDNA) segment was sequenced in combination with multilocus genotypes generated from 20 nuclear microsatellite loci for 201 individuals. The analysis of 627 bp of the C-terminal of cyt b and the hypervariable left domain of the noncoding control region (labeled as MDL fragment) sequences revealed the existence of two mtDNA lineages (α and β clade). Analysis of the MDL confirmed that North American captive Asian elephants belong to either the previously characterized α or β clade. An average nucleotide diversity of 0.017 was observed for the Asian elephant mtDNA MDL fragment sequences. Regardless whether an individual possessed mtDNA α or β clade haplotype, all individuals belonged to one nuclear gene lineage for the two X-linked (BGN and PHKA2) and one Y-linked (AMELY) genes sequenced. Analysis of multilocus genotypes indicated an average observed and expected heterozygosities were 0.543 and 0.539 in wild-sourced and 0.579 and 0.547 in the captive-born Asian elephants, respectively. No subdivision among the sampled individuals was detected, including data partitioned by mtDNA clades. Aside from parent–offspring dyads, no further relationships were detected among wild-sourced and captive-born Asian elephants (average relatedness value

Two geographically distinct populations of giraffe (Giraffa camelopardalis) were sampled for this study, the northern Namib Desert and Etosha National Park. Population genetic parameters and relationships within subpopulations were estimated to better understand the genetic architecture of this isolated subspecies. Gene flow between the geographically separated populations can be attributed to recent translocation of giraffe between the two populations. Inbreeding estimates in the six subpopulations studied were low though we found evidence that genetic drift may be affecting the genetic diversity of the isolated populations in northern Namibia. Population dynamics of the sampling locations was inferred with relationship coefficient analyses. Recent molecular systematics of the Namibian giraffe populations indicates that they are distinct from the subspecies Giraffa camelopardalis giraffa and classified as G. c. angolensis. Based on genetic analyses, these giraffe populations of northern Namibia, the desert-dwelling giraffe and those protected in Etosha National Park, are a distinct subspecies from that previously assumed; thus we add data on G. c. angolensis to our scientific knowledge of this giraffe of southern Africa.

Giraffe were historically free-ranging across most of sub-Saharan Africa but are now most often confined to national parks, conservation areas, or private ranches. Five viable populations of Rothschild’s giraffe (Giraffa camelopardalis rothschildi) remain in protected areas in Kenya and Uganda. The viable population in Uganda is Murchison Falls National Park and the four populations in Kenya are Lake Nakuru National Park (LNNP), Ruma National Park, Giraffe Manor, and Mwea Natural Reserve. The Kenya Wildlife Service queried a rapid decline in LNNP giraffe numbers falling from 153 individuals (1995) to 62 individuals (2002) and the failure of that population to recruit young in those years. Significantly reduced browse options, inbreeding depression and preferential lion predation were considered as potential reasons for this trend. Population genetic parameter estimates derived from multilocus genotype analyses suggest that the LNNP population was in good genetic health with respect to the likelihood of inbreeding depression. The population decline coincided with the drought attributed to the 1994 El Nino. Possible dietary complications from highly concentrated tannin levels because of forced over consumption of the park’s declining acacia trees may have compromised young giraffe, making them easy and opportunistic prey for the park’s lion population.

This study presents the first detailed morphometric measurements of wild caught black-and-white ruffed lemurs (Varecia variegata) from the eastern rainforests of Madagascar and aims to quantify the morphological variation present throughout their recognized range. One hundred and forty-four adult and juvenile individuals from 15 sites were sampled for 20 cranial, dental and postcranial morphometric and body mass measurements. Data were collected from an equal number of male and female individuals sampled across seasons over a 7-year period (1999–2002, 2004–2006). Results indicate that adult body mass and morphometric measurements varied between sexes across sites; however, the only significant intersexual difference found was that females possessed, on average, longer tails than males. Contrary to previous studies, significant seasonal variation could not be detected in either male or female body mass or testicular volume (i.e., breeding vs. nonbreeding, food-scarce vs. food-abundant seasons). Measurements did, however, vary significantly by site and subspecies, though clinal variation could not explain these differences. The introduced population from Nosy Mangabe exhibited significantly lower body mass and overall body length than all other populations; however, this distinction may not have been attributable to natural variation, and may have instead resulted from the ecologically restrictive habitat (e.g., unusually high lemur population densities, limited food resources, ecological isolation) of this introduced population. Finally, although fore-to-hindlimb, brachium-to-thigh and hindlimb indices were comparable to previous values, forelimb indices calculated here deviate significantly from previous reports, placing V. variegata within the upper range of lemurid taxa. It is currently unknown whether this is an artifact of sampling methods (i.e., live vs. skeletal specimens) or whether this is an avenue that warrants further investigation. Am. J. Primatol. 70:913–926, 2008. © 2008 Wiley-Liss, Inc.

Decken's sifaka (Propithecus deckeni deckeni) is found between the Mahavavy and Manambolo Rivers, in western Madagascar. Twenty-one polymorphic nuclear microsatellite loci were isolated from genomic DNA derived from a P. d. deckeni, from Tsingy de Bemaraha National Park. Population genetic parameters were estimated on 10 individuals each, sampled from Tsingy de Bemaraha National Park and Tsiombikibo Classified Forests. Significant null alleles were detected in seven loci which were dropped before population genetic parameters were re-estimated and compared to the full marker suite.

Twenty nuclear microsatellite loci were isolated from a genomic DNA library derived from a free-ranging red-bellied brown lemur (Eulemur rubriventer), from the Ranomafana National Park, Madagascar. Population genetic parameters were estimated as baseline values from samples collected from populations harboured in the Ranomafana and Andringitra National Parks. The marker suite will be used in a future study on the population dynamics of this species.

Twenty novel polymorphic microsatellite loci were isolated and characterized from the Indri, Indri indri, genome. Along with sequence data, this marker suite will be used in future studies to establish population structure throughout its range and to verify the proposed subspecific nomenclature. Gene diversity (0.760 and 0.783) and allelic richness (5.8 and 6.43) were estimated in the Betampona and Andasibe populations, respectively.

The Verreaux's sifaka (Propithecus verreauxi) is one of the species of Propithecus, living in the dry forest of southwest Madagascar. This species is endangered due to the loss and fragmentation of its natural habitat, a consequence of deforestation. Thirteen novel nuclear microsatellite loci were isolated and characterized in three populations of Verreaux's sifaka. The marker suite proved informative with an average of 8.9 alleles per locus and observed heterozygosity across the three populations of 0.675.

The black and white ruffed lemur, Varecia variegata , which is endemic to Madagascar, is under the threat of extinction due to the loss and fragmentation of its natural habitat, a consequence of deforestation. Behavioural researchers studying a population of V. variegata inhabiting the Manombo Special Reserve, noted that over a 4-year period, none of the family groups within the reserve produced offspring while those in neighbouring populations had been reproductively successful. Inbreeding depression was postulated as the trigger for this occurrence. However, another explanation exists. A cyclone, striking the region in 1997, destroyed a large percentage of the mature fruit-producing trees that V. variegata relied upon as a food source, which is likely to have produced a nutritional deficit. A panel of 25 simple sequence repeat (SSR) markers was utilised to assess the genetic diversity within four V. variegata populations, including individuals from Manombo and three other populations in southeastern Madagascar. The data revealed that the level of genetic diversity apparent within the Manombo population is comparable to the other groups studied. Therefore, it seems probable that genetic factors are not responsible for the recent lack of reproductive success on the part of the V. variegata at Manombo Special Reserve.

Twenty-two polymorphic microsatellite loci were isolated and characterized from the Avahi laniger genome. All were polymorphic in both the Eastern Woolly Lemur (A. laniger) and the Western Woolly Lemur (A. occidentalis). One locus, WOOL157, harboured allele structures that were species-specific. This marker suite will be used in future studies to establish the ranges and population structures of the two Avahi species on the island of Madagascar.

Twenty-one polymorphic microsatellite loci were isolated and characterized from the genome of the prehensile-tailed skink (Corucia zebrata). The markers were screened using a set of 16 individuals from the collection of the Philadelphia Zoo. The corresponding characterization indicated significant levels of heterozygosity and information potential for use in future studies. These markers will be a valuable tool in analysing the paternal contributions in twin birth questions and for population genetic studies in wild populations.

The Malagasy big-headed turtle (Erymnochelys madagascariensis) is the only Erymnochelys species living in lakes, rivers and watersheds of western Madagascar. This species is endangered due to over harvesting of natural populations for human consumption. Eleven nuclear microsatellite loci were isolated from a genomic DNA library derived from a free-ranging Malagasy big-headed turtle from the Beroboka Classified Forest, Madagascar. Population genetic parameters were estimated on 10 individuals sampled from Ampijoroa and Andranohobaka River, Madagascar, to determine marker utility and as preliminary baseline values to study future populations in these locations.

The Coquerel's sifaka (Propithecus coquereli) is one of the species of Propithecus, living in the dry forest of northwest Madagascar. This species is endangered due to the loss and fragmentation of its natural habitat, consequential of deforestation. Twenty nuclear microsatellite loci were isolated from genomic DNA derived from a free ranging Coquerel's sifaka from the Mariarano Classified Forest, Madagascar. Population genetic parameters were estimated as baseline values from samples collected in that forest.

Sixteen polymorphic microsatellite markers with an average allele size of k = 4.3 are identified from a genomic plasmid library constructed for giraffe (Giraffa camelopardalis ssp.). Primer sequences and marker data are reported in tabular form. The markers were screened in a population of 25 Maasai giraffe (G. c. tippelskirchi) collected near the Athi River, Kenya. The average observed heterozygosity for each marker was 0.36 with an average expected heterozygosity of 0.535. Hardy–Weinberg deviations are reported from this population, which is suspected to be inbred. The markers will be used to screen the captive giraffe population for subspecific or hybrid classification.