BackgroundTiming the origin of human malarias has been a focus of great interest. Previous studies on the mitochondrial genome concluded that Plasmodium in primates, including those parasitic to humans, radiated relatively recently during a process where host switches were common. Those investigations, however, assumed constant rate of evolution and tightly bound (fixed) calibration points based on host fossils or host distribution. We investigate the effect of such assumptions using different molecular dating methods. We include parasites from Lemuroidea since their distribution provides an external validation to time estimates allowing us to disregard scenarios that cannot explain their introduction in Madagascar.ResultsWe reject the assumption that the Plasmodium mitochondrial genome, as a unit or each gene separately, evolves at a constant rate. Our analyses show that Lemuroidea parasites are a monophyletic group that shares a common ancestor with all Catarrhini malarias except those related to P. falciparum. However, we found no evidence that this group of parasites branched with their hosts early in the evolution of primates. We applied relaxed clock methods and different calibrations points to explore the origin of primate malarias including those found in African apes. We showed that previous studies likely underestimated the origin of malarial parasites in primates.ConclusionsThe use of fossils from the host as absolute calibration and the assumption of a strict clock likely underestimate time when performing molecular dating analyses on malarial parasites. Indeed, by exploring different calibration points, we found that the time for the radiation of primate parasites may have taken place in the Eocene, a time consistent with the radiation of African anthropoids. The radiation of the four human parasite lineages was part of such events. The time frame estimated in this investigation, together with our phylogenetic analyses, made plausible a scenario where gorillas and humans acquired malaria from a Pan lineage.

The objective of this project was to better define the similarities and differences in gastrointestinal morphology present in lemur species. Measurements of the gastrointestinal tract of lemurs were obtained at necropsy from the captive population at Duke University Primate Center. Measurements of body length and weight, as well as gastrointestinal length, were recorded from five prosimian species: Propithecus tattersalli, Propithecus verreauxi, Varecia variegata, Hapalemur griseus, and Lemur catta. Photographs and measurements were used to obtain illustrations. Preliminary results suggest differences in gastrointestinal morphology among lemur species that coincide with differences in diet. Distinct sacculations in either the cecum or the colon were present for H. griseus, L. catta, P. verreauxi, and P. tattersalli, but not for V. variegata. The Propithecus specimens possessed a much greater ratio of gastrointestinal length to body length than the other three species. A short, blunt cecum and a shortened and sacculated colon were unique characteristics of the H. griseus specimens. These differences correlate well with a dietary shift from consumption of large amounts of structural plant cell wall (Propithecus sp.) to consumption of variable or moderate amounts (H. griseus, L. catta, and V. variegata). They also suggest that captive groups would benefit from further diet refinement in captivity. Am. J. Primatol. 52:133–142, 2000. © 2000 Wiley‐Liss, Inc.

If gut microbes influence host behavioral ecology in the short term, over evolutionary time, they could drive host niche differentiation. We explored this possibility by comparing the gut microbiota of Madagascar’s folivorous lemurs from Indriidae and Lepilemuridae. Occurring sympatrically in the eastern rainforest, our four, target species have different dietary specializations, including frugo-folivory (sifakas), young-leaf folivory (indri and woolly lemurs), and mature-leaf folivory (sportive lemurs). We collected fecal samples, from 2013 to 2017, and used amplicon sequencing, metagenomic sequencing, and nuclear magnetic resonance spectroscopy, respectively, to integrate analyses of gut microbiome structure and function with analysis of the colonic metabolome. The lemurs harbored species-specific microbiomes, metagenomes, and metabolomes that were tuned to their dietary specializations: Frugo-folivores had greater microbial and metagenomic diversity, and harbored generalist taxa. Mature-leaf folivores had greater individual microbiome variation, and taxa and metabolites putatively involved in cellulolysis. The consortia even differed between related, young-leaf specialists, with indri prioritizing metabolism of fiber and plant secondary compounds, and woolly lemurs prioritizing amino-acid cycling. Specialized gut microbiota and associated gastrointestinal morphologies enable folivores to variably tolerate resource fluctuation and support nutrient extraction from challenging resources (e.g., by metabolizing plant secondary compounds or recalcitrant fibers), perhaps ultimately facilitating host species’ diversity and specialized feeding ecologies.

Neoplastic diseases in prosimians have been sporadically reported in the literature. To provide a comprehensive review of prosimian neoplasia, a retrospective evaluation of neoplasia in a large captive prosimian colony and an extensive literature review were performed. Primates that belong to the Order Primata, Suborder Prosimii with histologic evidence of neoplasia were included. One hundred twenty-three cases of spontaneous neoplasia were identified in 101 prosimians from the Duke Lemur Center, and 124 cases were reported in 116 prosimians in the literature. Overall, this review compiled a total of 247 neoplasms in 217 prosimians. Of the 217 affected animals, 88 of 217 were males (41%), 100 of 217 were females (46%), and sex was not reported in 29 of 217 (13%). Ages ranged from 2 days to 36 years. Prosimian families represented were Lemuridae (80/217 [37%]), Cheirogaleidae (61/217 [28%]), Galagidae (44/217 [20%]), Lorisidae (28/217 [13%]), and Indriidae (4/217 [2%]). The most commonly affected species were the gray mouse lemur (Microcebus murinus) (28/217 [13%]), thick-tailed greater bush baby (Otolemur crassicaudatus) (23/217 [11%]), and black lemur (Eulemur macaco) (19/217 [9%]). Organ systems affected, in order of descending occurrence, were digestive (75/247 [30%]), reproductive (40/247 [16%]), hematopoietic (34/247 [14%]), integumentary (28/247 [11%]), endocrine (26/247 [11%]), and urinary (17/247 [7%]). The respiratory, nervous, musculoskeletal, and cardiovascular systems were infrequently affected. The most common neoplasms were hepatocellular (32/247 [13%]), lymphoma and/or leukemia (29/247 [12%]), biliary (15/247 [6%]), and mammary neoplasms (12/247 [5%]). This article should serve as a valuable reference for the types and relative frequencies of neoplasms that occur in prosimian species.

The consequences of inbreeding have been well studied in a variety of taxa, revealing that inbreeding has major negative impacts in numerous species, both in captivity and in the wild; however, as trans-generational health data are difficult to obtain for long-lived, free-ranging species, similar analyses are generally lacking for nonhuman primates. Here, we examined the long-term effects of inbreeding on numerous health estimates in a captive colony of ring-tailed lemurs (Lemur catta), housed under semi-natural conditions. This vulnerable strepsirrhine primate is endemic to Madagascar, a threatened hotspot of biodiversity; consequently, this captive population represents an important surrogate. Despite significant attention to maintaining the genetic diversity of captive animals, breeding colonies invariably suffer from various degrees of inbreeding. We used neutral heterozygosity as an estimate of inbreeding and showed that our results reflect genome-wide inbreeding, rather than local genetic effects. In particular, we found that genetic diversity affects several fitness correlates, including the prevalence and burden of Cuterebra parasites and a third (N = 6) of the blood parameters analyzed, some of which reflect immunocompetence. As a final validation of inbreeding depression in this captive colony, we showed that, compared to outbred individuals, inbred lemurs were more likely to die earlier from diseases. Through these analyses, we highlight the importance of monitoring genetic variation in captive animals-a key objective for conservation geneticists-and provide insight into the potential negative consequences faced by small or isolated populations in the wild.

will be interesting to see how the reformed NHS deals with this question. This is vet another reason for our erring on the side of financial caution. ConclusionWe have to ask ourselves whether or not we are really enhancing patient choice and using monev to the best effect. What is absolutely certain is that we are spending a lot of management and clinical time making decisions on a relatively small number of patients. This time may not be used to its best advantage.

The N1303K mutation was identified in the second nucleotide binding fold of the cystic fibrosis (CF) gene last year. We have gathered data from laboratories throughout Europe and the United States of America in order to estimate its frequency and to attempt to characterise the clinical manifestations of this mutation. N1303K, identified on 216 of nearly 15,000 CF chromosomes tested, accounts for 1.5% of all CF chromosomes. The frequency of the N1303K allele varies significantly between countries and ethnic groups, being more common in Southern than in Northern Europe. This variation is independent of the delta F508 allele. It was not found on UK Asian, American Black or Australian chromosomes. N1303K is associated with four different linked marker haplotypes for the polymorphic markers XV-2c, KM.19 and pMP6d-9. Ten patients are homozygous for this mutation, whereas 106 of the remainder carry one of 12 known CF mutations in the other CF allele. We classify N1303K as a "severe" mutation with respect to the pancreas, but can find no correlation between this mutation, in either the homozygous or heterozygous state, and the severity of lung disease.

Few mammals-cetaceans, domestic cats and select bats and rodents-can send and receive vocal signals contained within the ultrasonic domain, or pure ultrasound (greater than 20 kHz). Here, we use the auditory brainstem response (ABR) method to demonstrate that a species of nocturnal primate, the Philippine tarsier (Tarsius syrichta), has a high-frequency limit of auditory sensitivity of ca 91 kHz. We also recorded a vocalization with a dominant frequency of 70 kHz. Such values are among the highest recorded for any terrestrial mammal, and a relatively extreme example of ultrasonic communication. For Philippine tarsiers, ultrasonic vocalizations might represent a private channel of communication that subverts detection by predators, prey and competitors, enhances energetic efficiency, or improves detection against low-frequency background noise.