Three species of boid snakes are recognized in Madagascar, namely the genus Sanzinia (one species... more Three species of boid snakes are recognized in Madagascar, namely the genus Sanzinia (one species and two subspecies) and the genus Acrantophis (two species). In the present study, we studied the patterns of genetic variation of these species across Madagascar using a fragment of the mitochondrial 16S rRNA gene in 77 specimens. To support the phylogenetic relationships of the lineages identified, three further gene fragments (cytochrome b, 12S rRNA and c-mos) were analyzed in a reduced but representative set of samples. The results obtained corroborate that the genus Sanzinia includes two highly divergent mitochondrial lineages that evolved independently from each other on the east versus the west side of Madagascar. Each of these lineages presents a further subdivision that separates northern from southern groups. The nuclear marker showed no variation among the Malagasy boas, indicating either very low substitution rates in this gene or relatively recent speciation events coupled ...
A new species of dwarf lemur, Cheirogaleus shethi sp. nov., of the C. medius group is described f... more A new species of dwarf lemur, Cheirogaleus shethi sp. nov., of the C. medius group is described from the dry and transitional forests of northern Madagascar. This species can be found along the forest corridor from Ankarana Special Reserve east to the Analamerana Special Reserve down to the Bekaraoka forest in the Loky-Manambato Protected Area. This species is genetically distinct from other members of the C. medius species group and is sister to a poorly known lineage in Sambava. The identification of this new species highlights the importance of northern Madagascar as a reservoir of biodiversity.
Dyscophus antongilii and D. guineti are two morphologically very similar microhylid frogs from Ma... more Dyscophus antongilii and D. guineti are two morphologically very similar microhylid frogs from Mada-gascar of uncertain taxonomy. D. antongilii is currently included in Appendix I of the Convention on the International Trade in Endangered Species (CITES) and its exportation is banned completely. In contrast, D. guineti does not receive any legal protection and it is regularly exported. Field data on ecology and behaviour are to a large extent lacking. Here we report on a genetic survey of D. antongilii and D. guineti using nuclear and mitochondrial DNA markers. Sequences of a fragment of 501 bp of the mitochondrial cytochrome b gene from one population of D. antongilii and two populations of D. guineti resulted in a single haplotype network, without haplotype sharing among the populations. However, haplotypes of D. guineti were only 1–4 mutational steps from those of D. antongilii, and did not form a clade. The analysis of eight microsatellites newly developed and standardized for D...
Abstract.—Squamate reptiles (snakes, lizards, and amphisbaenians) serve as model systems for evol... more Abstract.—Squamate reptiles (snakes, lizards, and amphisbaenians) serve as model systems for evolutionary studies of a variety of morphological and behavioral traits, and phylogeny is crucial to many generalizations derived from such studies. Specifically, the traditional dichotomy between Iguania (anoles, iguanas, chameleons, etc.) and Scleroglossa (skinks, geckos, snakes, etc.) has been correlated with major evolutionary shifts within Squamata. We present a molecular phylogenetic study of 69 squamate species using approximately 4600 (2876 parsimony-informative) base pairs (bp) of DNA sequence data from the nuclear genes RAG-1 (∼2750 bp) and c-mos (∼360 bp) and the mitochondrial ND2 region (∼1500 bp), sampling all major clades and most major subclades. Under our hypothesis, species previously placed in Iguania, Anguimorpha, and almost all recognized squamate families form strongly supported monophyletic groups. However, species previously placed in Scleroglossa, Varanoidea, and sev...
A core set of microsatellite markers for conservation genetics studies of Korean goral (Naemorhed... more A core set of microsatellite markers for conservation genetics studies of Korean goral (Naemorhedus caudatus) and its cross-species amplification in Caprinae species
The critically endangered ploughshare tortoise, Astrochelys yniphora, is endemic to the Baly Bay ... more The critically endangered ploughshare tortoise, Astrochelys yniphora, is endemic to the Baly Bay region of western Madagascar. In 2015, the wild population was estimated to be < 500 subadults/adults across a fragmented habitat, with subsequent field surveys reporting a further decline to a perilously low number of adult tortoises. The primary cause of this decline was poaching for the illegal international pet trade, which has escalated since 2006 leading to the extirpation of ploughshare tortoises from at least two localities. Seizures of smuggled tortoises increased over this same period, with most confiscated animals being incorporated into assurance populations. This study presents a genetic reference, including samples from the extirpated localities. Mitochondrial sequence data and 25 nuclear microsatellite markers were utilized to estimate genetic diversity of the wild population prior to a > 50% decline, identify Management Units (MUs), and present a dataset to assign confiscated individuals to their subpopulation of origin. Despite a long history of exploitation, heterozygosity appeared healthy, ranging from 0.612 to 0.758 across four localities, and no recent genetic bottlenecks were observed. In contrast, the Western Complex, consisting of the Ambatomainty, Andrafiafaly, and Andranolava regions, exhibited a possible decline in allelic diversity. Four genetic clusters were recovered and used to define three MUs corresponding to the following localities: Cap Sada, Beheta, and a combined Western Complex plus Betainalika. Results are discussed in the context of conservation genetic management advising that MUs be treated as conservation units for wild and captive management to maintain the breadth of genetic diversity present in the wild.
Tigers are among the most charismatic of endangered species, yet little is known about their evol... more Tigers are among the most charismatic of endangered species, yet little is known about their evolutionary history. We sequenced 65 individual genomes representing extant tiger geographic range. We found strong genetic differentiation between putative tiger subspecies, divergence within the last 10,000 years, and demographic histories dominated by population bottlenecks. Indian tigers have substantial genetic variation and substructure stemming from population isolation and intense recent bottlenecks here. Despite high genetic diversity across India, individual tigers host longer runs of homozygosity, potentially suggesting recent inbreeding here. Amur tiger genomes revealed the strongest signals of selection and over-representation of gene ontology categories potentially involved in metabolic adaptation to cold. Novel insights highlight the antiquity of northeast Indian tigers. Our results demonstrate recent evolution, with differential isolation, selection and drift in extant tiger...
The Philippine crocodile (Crocodylus mindorensis) is considered one of the most endangered of the... more The Philippine crocodile (Crocodylus mindorensis) is considered one of the most endangered of the crocodilian species.Rumors or anecdotal concerns have existed for some time as to the possibility of hybrid individuals existing in a captivecollection under consideration for providing reintroduction candidates; however, visual observations failed to identify sus-pected hybrids. Samples were collected from 619 Philippine crocodiles from several captive facilities and two free-rang-ing populations. Mitochondrial DNA D-loop (601 bp) fragments were sequenced for each crocodile and compared to 28individuals representing ten crocodile species. Among Philippine crocodiles, 48 variable sites (47 parsimony informativesites) were identified, which defined six C. mindorensis haplotypes and one C. porosus-derived haplotype. Data were alsogenerated for a 965 bp fragment of the ND4 subunit gene fragment for two samples of each D-loop haplotype. Amongthem, 91 variable sites (90 parsimony informative...
Endemic to Madagascar, the genus Uroplatus of the family Gekkonidae consists of 13 nominal specie... more Endemic to Madagascar, the genus Uroplatus of the family Gekkonidae consists of 13 nominal species of leaf-tailed geckos. These forest dwelling lizards are famous for their cryptic and odd appearance. We describe a new species of the Uroplatus ebenaui group from the Montagne d’Ambre massif in northern Madagascar. Uroplatus finiavana sp. nov., is morphologically similar to the sympatric U. ebenaui but differs in multiple character state expressions, among which are a longer tail and an unpigmentated oral mucosa. It also can be differentiated from U. ebenaui and all other Uroplatus species based on a high level of divergence in the mitochondrial ND4 gene and the nuclear C-mos gene, and no instances of haplotype sharing exist in these genes among the analysed species. The new species is relatively abundant at Montagne d'Ambre National Park where at lower elevations (ca. 700 m) it occurs together with U. ebenaui, without any signal of genetic admixture. Records of U. ebenaui in the ...
Chameleons of the Madagascan endemic genus Brookesia Gray are small to extremely small reptiles w... more Chameleons of the Madagascan endemic genus Brookesia Gray are small to extremely small reptiles with a mostly terrestrial lifestyle, and due to their low mobility and their camouflage they are nearly invisible in the leaf litter of Madagascar's forests. The genus Brookesia is widely distributed (except in the arid south and south-west) but many Brookesia species are restricted to a relatively small area of the island (Glaw & Vences 2007). Speciation has been most prolific in the northern parts of Madagascar, an area that currently host about two-thirds of the 27 nominal Brookesia species (Raxworthy & Nussbaum 1995; Glaw & Vences 2007; Townsend et al. 2009).
The greater bamboo lemur (Prolemur simus) is a member of the Family Lemuridae that is unique in t... more The greater bamboo lemur (Prolemur simus) is a member of the Family Lemuridae that is unique in their dependency on bamboo as a primary food source. This Critically Endangered species lives in small forest patches in eastern Madagascar, occupying a fraction of its historical range. Here we sequence the genome of the greater bamboo lemur for the first time, and provide genome resources for future studies of this species that can be applied across its distribution. Following whole genome sequencing of five individuals we identified over 152,000 polymorphic single nucleotide variants (SNVs), and evaluated geographic structuring across nearly 19 k SNVs. We characterized a stronger signal associated with a north-south divide than across elevations for our limited samples. We also evaluated the demographic history of this species, and infer a dramatic population crash. This species had the largest effective population size (estimated between ~ 900,000 to one million individuals) between a...
Aye-aye (Daubentonia madagascariensis) feeding behavior has become synonymous with deadwood forag... more Aye-aye (Daubentonia madagascariensis) feeding behavior has become synonymous with deadwood foraging. However, deadwood is not always the most frequently used substrate, as some aye-ayes use live trees more often to access invertebrates. We sought to compare the frequency of aye-aye invertebrate foraging in deadwood and live trees to better understand their feeding behaviors. We followed two male aye-ayes at Kianjavato, a heavily disturbed habitat in southeastern Madagascar, from October 2013 to October 2014, and one male and one female aye-aye at Torotorofotsy, a continuous forest in eastern Madagascar, from July 2014 to December 2015. We collected feeding data by recording the behavior of a focal aye-aye every 5 min for a total of 373 h at Kianjavato and 383 h at Torotorofotsy. Our results showed no difference in the amount of deadwood used between the individuals. However, there was a significant difference in the amount of live tree feeding between the female at Torotorofotsy an...
Folia primatologica; international journal of primatology, 2018
Previous studies found that aye-ayes (Daubentonia madagascariensis) consume a variety of non-inve... more Previous studies found that aye-ayes (Daubentonia madagascariensis) consume a variety of non-invertebrate resources, supporting the hypothesis that aye-ayes are too large-bodied to focus feeding efforts on insects. However, these conclusions were based on introduced populations, with little known about aye-aye behaviour and ecology in its natural habitat. This study investigates activity budgets, diet, and home range/territories of 2 male aye-ayes in the Kianjavato Classified Forest, a disturbed forest in south-eastern Madagascar, from October 2013 to October 2014. We used radiotelemetry and focal-animal sampling methods to collect behavioural data. We recorded GPS coordinates of the focal animal every 20 min, calculating the home range size for each individual. Results showed that male aye-ayes spent most of their time feeding and travelling. Their feeding time primarily focussed on larvae and adult insects from various substrates, and to a lesser extent Canarium spp. seeds. Home r...
General and comparative endocrinology, Nov 6, 2017
The critically endangered Radiated Tortoise (Astrochelys radiata) is endemic to the southern coas... more The critically endangered Radiated Tortoise (Astrochelys radiata) is endemic to the southern coastlines of Madagascar. Once common, wild populations of this tortoise have undergone dramatic declines in recent years. Although there have been studies documenting reproductive activities, reproductive physiological parameters are unknown yet may be crucial in the recovery of the species. Over four research seasons in remote field locations native to A. radiata, we surveyed for, radio-tracked, and sampled wild, free ranging tortoises. We sampled and measured stress and reproductive parameters (corticosterone [CORT], testosterone [T], estradiol-17β [E2], and progesterone [P]) in 311 plasma samples from 203 wild A. radiata, capturing their active period. Generally, hormone concentrations were associated with body condition, temperature, and humidity. There was wide variation in CORT that varied monthly and by group. Juvenile tortoises maintained more than twice the mean basal CORT concentr...
We investigated the acute stress response associated with animal personalities by measuring plasm... more We investigated the acute stress response associated with animal personalities by measuring plasma glucocorticoids throughout handling and collected ~2 years of movement and behavioural data in a wild, Critically Endangered animal, Astrochelys radiata (radiated tortoise). To determine whether our standard, brief conscientious handling procedures induce a stress response in our target species, we applied a stressor by way of initial animal processing and deployment of telemetry equipment. During surveys and processing, we sampled animals immediately upon detection, again after completing transmitter attachment and processing, and a final time the following day. We then used radiotelemetry to follow a subset of the animals for 22 months while collecting behavioural, climatic and location data. We found that brief and conscientious handling did not illicit consistent changes in plasma concentrations of the stress hormone corticosterone (CORT) but did reveal tremendous individual variat...
Some primate populations include both trichromatic and dichromatic (red-green colour blind) indiv... more Some primate populations include both trichromatic and dichromatic (red-green colour blind) individuals due to allelic variation at the X-linked opsin locus. This polymorphic trichromacy is well described in day-active New World monkeys. Less is known about colour vision in Malagasy lemurs, but, unlike New World monkeys, only some day-active lemurs are polymorphic, while others are dichromatic. The evolutionary pressures underlying these differences in lemurs are unknown, but aspects of species ecology, including variation in activity pattern, are hypothesized to play a role. Limited data on X-linked opsin variation in lemurs make such hypotheses difficult to evaluate. We provide the first detailed examination of X-linked opsin variation across a lemur clade (Indriidae). We sequenced the X-linked opsin in the most strictly diurnal and largest extant lemur, Indri indri, and nine species of smaller, generally diurnal indriids (Propithecus). Although nocturnal Avahi (sister taxon to Pr...
Three species of boid snakes are recognized in Madagascar, namely the genus Sanzinia (one species... more Three species of boid snakes are recognized in Madagascar, namely the genus Sanzinia (one species and two subspecies) and the genus Acrantophis (two species). In the present study, we studied the patterns of genetic variation of these species across Madagascar using a fragment of the mitochondrial 16S rRNA gene in 77 specimens. To support the phylogenetic relationships of the lineages identified, three further gene fragments (cytochrome b, 12S rRNA and c-mos) were analyzed in a reduced but representative set of samples. The results obtained corroborate that the genus Sanzinia includes two highly divergent mitochondrial lineages that evolved independently from each other on the east versus the west side of Madagascar. Each of these lineages presents a further subdivision that separates northern from southern groups. The nuclear marker showed no variation among the Malagasy boas, indicating either very low substitution rates in this gene or relatively recent speciation events coupled ...
A new species of dwarf lemur, Cheirogaleus shethi sp. nov., of the C. medius group is described f... more A new species of dwarf lemur, Cheirogaleus shethi sp. nov., of the C. medius group is described from the dry and transitional forests of northern Madagascar. This species can be found along the forest corridor from Ankarana Special Reserve east to the Analamerana Special Reserve down to the Bekaraoka forest in the Loky-Manambato Protected Area. This species is genetically distinct from other members of the C. medius species group and is sister to a poorly known lineage in Sambava. The identification of this new species highlights the importance of northern Madagascar as a reservoir of biodiversity.
Dyscophus antongilii and D. guineti are two morphologically very similar microhylid frogs from Ma... more Dyscophus antongilii and D. guineti are two morphologically very similar microhylid frogs from Mada-gascar of uncertain taxonomy. D. antongilii is currently included in Appendix I of the Convention on the International Trade in Endangered Species (CITES) and its exportation is banned completely. In contrast, D. guineti does not receive any legal protection and it is regularly exported. Field data on ecology and behaviour are to a large extent lacking. Here we report on a genetic survey of D. antongilii and D. guineti using nuclear and mitochondrial DNA markers. Sequences of a fragment of 501 bp of the mitochondrial cytochrome b gene from one population of D. antongilii and two populations of D. guineti resulted in a single haplotype network, without haplotype sharing among the populations. However, haplotypes of D. guineti were only 1–4 mutational steps from those of D. antongilii, and did not form a clade. The analysis of eight microsatellites newly developed and standardized for D...
Abstract.—Squamate reptiles (snakes, lizards, and amphisbaenians) serve as model systems for evol... more Abstract.—Squamate reptiles (snakes, lizards, and amphisbaenians) serve as model systems for evolutionary studies of a variety of morphological and behavioral traits, and phylogeny is crucial to many generalizations derived from such studies. Specifically, the traditional dichotomy between Iguania (anoles, iguanas, chameleons, etc.) and Scleroglossa (skinks, geckos, snakes, etc.) has been correlated with major evolutionary shifts within Squamata. We present a molecular phylogenetic study of 69 squamate species using approximately 4600 (2876 parsimony-informative) base pairs (bp) of DNA sequence data from the nuclear genes RAG-1 (∼2750 bp) and c-mos (∼360 bp) and the mitochondrial ND2 region (∼1500 bp), sampling all major clades and most major subclades. Under our hypothesis, species previously placed in Iguania, Anguimorpha, and almost all recognized squamate families form strongly supported monophyletic groups. However, species previously placed in Scleroglossa, Varanoidea, and sev...
A core set of microsatellite markers for conservation genetics studies of Korean goral (Naemorhed... more A core set of microsatellite markers for conservation genetics studies of Korean goral (Naemorhedus caudatus) and its cross-species amplification in Caprinae species
The critically endangered ploughshare tortoise, Astrochelys yniphora, is endemic to the Baly Bay ... more The critically endangered ploughshare tortoise, Astrochelys yniphora, is endemic to the Baly Bay region of western Madagascar. In 2015, the wild population was estimated to be < 500 subadults/adults across a fragmented habitat, with subsequent field surveys reporting a further decline to a perilously low number of adult tortoises. The primary cause of this decline was poaching for the illegal international pet trade, which has escalated since 2006 leading to the extirpation of ploughshare tortoises from at least two localities. Seizures of smuggled tortoises increased over this same period, with most confiscated animals being incorporated into assurance populations. This study presents a genetic reference, including samples from the extirpated localities. Mitochondrial sequence data and 25 nuclear microsatellite markers were utilized to estimate genetic diversity of the wild population prior to a > 50% decline, identify Management Units (MUs), and present a dataset to assign confiscated individuals to their subpopulation of origin. Despite a long history of exploitation, heterozygosity appeared healthy, ranging from 0.612 to 0.758 across four localities, and no recent genetic bottlenecks were observed. In contrast, the Western Complex, consisting of the Ambatomainty, Andrafiafaly, and Andranolava regions, exhibited a possible decline in allelic diversity. Four genetic clusters were recovered and used to define three MUs corresponding to the following localities: Cap Sada, Beheta, and a combined Western Complex plus Betainalika. Results are discussed in the context of conservation genetic management advising that MUs be treated as conservation units for wild and captive management to maintain the breadth of genetic diversity present in the wild.
Tigers are among the most charismatic of endangered species, yet little is known about their evol... more Tigers are among the most charismatic of endangered species, yet little is known about their evolutionary history. We sequenced 65 individual genomes representing extant tiger geographic range. We found strong genetic differentiation between putative tiger subspecies, divergence within the last 10,000 years, and demographic histories dominated by population bottlenecks. Indian tigers have substantial genetic variation and substructure stemming from population isolation and intense recent bottlenecks here. Despite high genetic diversity across India, individual tigers host longer runs of homozygosity, potentially suggesting recent inbreeding here. Amur tiger genomes revealed the strongest signals of selection and over-representation of gene ontology categories potentially involved in metabolic adaptation to cold. Novel insights highlight the antiquity of northeast Indian tigers. Our results demonstrate recent evolution, with differential isolation, selection and drift in extant tiger...
The Philippine crocodile (Crocodylus mindorensis) is considered one of the most endangered of the... more The Philippine crocodile (Crocodylus mindorensis) is considered one of the most endangered of the crocodilian species.Rumors or anecdotal concerns have existed for some time as to the possibility of hybrid individuals existing in a captivecollection under consideration for providing reintroduction candidates; however, visual observations failed to identify sus-pected hybrids. Samples were collected from 619 Philippine crocodiles from several captive facilities and two free-rang-ing populations. Mitochondrial DNA D-loop (601 bp) fragments were sequenced for each crocodile and compared to 28individuals representing ten crocodile species. Among Philippine crocodiles, 48 variable sites (47 parsimony informativesites) were identified, which defined six C. mindorensis haplotypes and one C. porosus-derived haplotype. Data were alsogenerated for a 965 bp fragment of the ND4 subunit gene fragment for two samples of each D-loop haplotype. Amongthem, 91 variable sites (90 parsimony informative...
Endemic to Madagascar, the genus Uroplatus of the family Gekkonidae consists of 13 nominal specie... more Endemic to Madagascar, the genus Uroplatus of the family Gekkonidae consists of 13 nominal species of leaf-tailed geckos. These forest dwelling lizards are famous for their cryptic and odd appearance. We describe a new species of the Uroplatus ebenaui group from the Montagne d’Ambre massif in northern Madagascar. Uroplatus finiavana sp. nov., is morphologically similar to the sympatric U. ebenaui but differs in multiple character state expressions, among which are a longer tail and an unpigmentated oral mucosa. It also can be differentiated from U. ebenaui and all other Uroplatus species based on a high level of divergence in the mitochondrial ND4 gene and the nuclear C-mos gene, and no instances of haplotype sharing exist in these genes among the analysed species. The new species is relatively abundant at Montagne d'Ambre National Park where at lower elevations (ca. 700 m) it occurs together with U. ebenaui, without any signal of genetic admixture. Records of U. ebenaui in the ...
Chameleons of the Madagascan endemic genus Brookesia Gray are small to extremely small reptiles w... more Chameleons of the Madagascan endemic genus Brookesia Gray are small to extremely small reptiles with a mostly terrestrial lifestyle, and due to their low mobility and their camouflage they are nearly invisible in the leaf litter of Madagascar's forests. The genus Brookesia is widely distributed (except in the arid south and south-west) but many Brookesia species are restricted to a relatively small area of the island (Glaw & Vences 2007). Speciation has been most prolific in the northern parts of Madagascar, an area that currently host about two-thirds of the 27 nominal Brookesia species (Raxworthy & Nussbaum 1995; Glaw & Vences 2007; Townsend et al. 2009).
The greater bamboo lemur (Prolemur simus) is a member of the Family Lemuridae that is unique in t... more The greater bamboo lemur (Prolemur simus) is a member of the Family Lemuridae that is unique in their dependency on bamboo as a primary food source. This Critically Endangered species lives in small forest patches in eastern Madagascar, occupying a fraction of its historical range. Here we sequence the genome of the greater bamboo lemur for the first time, and provide genome resources for future studies of this species that can be applied across its distribution. Following whole genome sequencing of five individuals we identified over 152,000 polymorphic single nucleotide variants (SNVs), and evaluated geographic structuring across nearly 19 k SNVs. We characterized a stronger signal associated with a north-south divide than across elevations for our limited samples. We also evaluated the demographic history of this species, and infer a dramatic population crash. This species had the largest effective population size (estimated between ~ 900,000 to one million individuals) between a...
Aye-aye (Daubentonia madagascariensis) feeding behavior has become synonymous with deadwood forag... more Aye-aye (Daubentonia madagascariensis) feeding behavior has become synonymous with deadwood foraging. However, deadwood is not always the most frequently used substrate, as some aye-ayes use live trees more often to access invertebrates. We sought to compare the frequency of aye-aye invertebrate foraging in deadwood and live trees to better understand their feeding behaviors. We followed two male aye-ayes at Kianjavato, a heavily disturbed habitat in southeastern Madagascar, from October 2013 to October 2014, and one male and one female aye-aye at Torotorofotsy, a continuous forest in eastern Madagascar, from July 2014 to December 2015. We collected feeding data by recording the behavior of a focal aye-aye every 5 min for a total of 373 h at Kianjavato and 383 h at Torotorofotsy. Our results showed no difference in the amount of deadwood used between the individuals. However, there was a significant difference in the amount of live tree feeding between the female at Torotorofotsy an...
Folia primatologica; international journal of primatology, 2018
Previous studies found that aye-ayes (Daubentonia madagascariensis) consume a variety of non-inve... more Previous studies found that aye-ayes (Daubentonia madagascariensis) consume a variety of non-invertebrate resources, supporting the hypothesis that aye-ayes are too large-bodied to focus feeding efforts on insects. However, these conclusions were based on introduced populations, with little known about aye-aye behaviour and ecology in its natural habitat. This study investigates activity budgets, diet, and home range/territories of 2 male aye-ayes in the Kianjavato Classified Forest, a disturbed forest in south-eastern Madagascar, from October 2013 to October 2014. We used radiotelemetry and focal-animal sampling methods to collect behavioural data. We recorded GPS coordinates of the focal animal every 20 min, calculating the home range size for each individual. Results showed that male aye-ayes spent most of their time feeding and travelling. Their feeding time primarily focussed on larvae and adult insects from various substrates, and to a lesser extent Canarium spp. seeds. Home r...
General and comparative endocrinology, Nov 6, 2017
The critically endangered Radiated Tortoise (Astrochelys radiata) is endemic to the southern coas... more The critically endangered Radiated Tortoise (Astrochelys radiata) is endemic to the southern coastlines of Madagascar. Once common, wild populations of this tortoise have undergone dramatic declines in recent years. Although there have been studies documenting reproductive activities, reproductive physiological parameters are unknown yet may be crucial in the recovery of the species. Over four research seasons in remote field locations native to A. radiata, we surveyed for, radio-tracked, and sampled wild, free ranging tortoises. We sampled and measured stress and reproductive parameters (corticosterone [CORT], testosterone [T], estradiol-17β [E2], and progesterone [P]) in 311 plasma samples from 203 wild A. radiata, capturing their active period. Generally, hormone concentrations were associated with body condition, temperature, and humidity. There was wide variation in CORT that varied monthly and by group. Juvenile tortoises maintained more than twice the mean basal CORT concentr...
We investigated the acute stress response associated with animal personalities by measuring plasm... more We investigated the acute stress response associated with animal personalities by measuring plasma glucocorticoids throughout handling and collected ~2 years of movement and behavioural data in a wild, Critically Endangered animal, Astrochelys radiata (radiated tortoise). To determine whether our standard, brief conscientious handling procedures induce a stress response in our target species, we applied a stressor by way of initial animal processing and deployment of telemetry equipment. During surveys and processing, we sampled animals immediately upon detection, again after completing transmitter attachment and processing, and a final time the following day. We then used radiotelemetry to follow a subset of the animals for 22 months while collecting behavioural, climatic and location data. We found that brief and conscientious handling did not illicit consistent changes in plasma concentrations of the stress hormone corticosterone (CORT) but did reveal tremendous individual variat...
Some primate populations include both trichromatic and dichromatic (red-green colour blind) indiv... more Some primate populations include both trichromatic and dichromatic (red-green colour blind) individuals due to allelic variation at the X-linked opsin locus. This polymorphic trichromacy is well described in day-active New World monkeys. Less is known about colour vision in Malagasy lemurs, but, unlike New World monkeys, only some day-active lemurs are polymorphic, while others are dichromatic. The evolutionary pressures underlying these differences in lemurs are unknown, but aspects of species ecology, including variation in activity pattern, are hypothesized to play a role. Limited data on X-linked opsin variation in lemurs make such hypotheses difficult to evaluate. We provide the first detailed examination of X-linked opsin variation across a lemur clade (Indriidae). We sequenced the X-linked opsin in the most strictly diurnal and largest extant lemur, Indri indri, and nine species of smaller, generally diurnal indriids (Propithecus). Although nocturnal Avahi (sister taxon to Pr...
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Papers by Edward Louis