Zoological Society of San Diego

About: Zoological Society of San Diego is a nonprofit organization based out in San Diego, California, United States. It is known for research contribution in the topics: Population & Animal ecology. The organization has 427 authors who have published 669 publications receiving 36032 citations.

Evolution of mammals and their gut microbes

Abstract: Mammals are metagenomic in that they are composed of not only their own gene complements but also those of all of their associated microbes. To understand the coevolution of the mammals and their indigenous microbial communities, we conducted a network-based analysis of bacterial 16S ribosomal RNA gene sequences from the fecal microbiota of humans and 59 other mammalian species living in two zoos and in the wild. The results indicate that host diet and phylogeny both influence bacterial diversity, which increases from carnivory to omnivory to herbivory; that bacterial communities codiversified with their hosts; and that the gut microbiota of humans living a modern life-style is typical of omnivorous primates.

Diclofenac residues as the cause of vulture population decline in Pakistan

Abstract: The Oriental white-backed vulture (OWBV; Gyps bengalensis) was once one of the most common raptors in the Indian subcontinent A population decline of >95%, starting in the 1990s, was first noted at Keoladeo National Park, India Since then, catastrophic declines, also involving Gyps indicus and Gyps tenuirostris, have continued to be reported across the subcontinent Consequently these vultures are now listed as critically endangered by BirdLife International In 2000, the Peregrine Fund initiated its Asian Vulture Crisis Project with the Ornithological Society of Pakistan, establishing study sites at 16 OWBV colonies in the Kasur, Khanewal and Muzaffargarh-Layyah Districts of Pakistan to measure mortality at over 2,400 active nest sites Between 2000 and 2003, high annual adult and subadult mortality (5-86%) and resulting population declines (34-95%) (ref 5 and MG, manuscript in preparation) were associated with renal failure and visceral gout Here, we provide results that directly correlate residues of the anti-inflammatory drug diclofenac with renal failure Diclofenac residues and renal disease were reproduced experimentally in OWBVs by direct oral exposure and through feeding vultures diclofenac-treated livestock We propose that residues of veterinary diclofenac are responsible for the OWBV decline

Molecular phylogenetics and the origins of placental mammals

Abstract: The precise hierarchy of ancient divergence events that led to the present assemblage of modern placental mammals has been an area of controversy among morphologists, palaeontologists and molecular evolutionists. Here we address the potential weaknesses of limited character and taxon sampling in a comprehensive molecular phylogenetic analysis of 64 species sampled across all extant orders of placental mammals. We examined sequence variation in 18 homologous gene segments (including nearly 10,000 base pairs) that were selected for maximal phylogenetic informativeness in resolving the hierarchy of early mammalian divergence. Phylogenetic analyses identify four primary superordinal clades: (I) Afrotheria (elephants, manatees, hyraxes, tenrecs, aardvark and elephant shrews); (II) Xenarthra (sloths, anteaters and armadillos); (III) Glires (rodents and lagomorphs), as a sister taxon to primates, flying lemurs and tree shrews; and (IV) the remaining orders of placental mammals (cetaceans, artiodactyls, perissodactyls, carnivores, pangolins, bats and core insectivores). Our results provide new insight into the pattern of the early placental mammal radiation.

Resolution of the early placental mammal radiation using Bayesian phylogenetics

Abstract: Molecular phylogenetic studies have resolved placental mammals into four major groups, but have not established the full hierarchy of interordinal relationships, including the position of the root. The latter is critical for understanding the early biogeographic history of placentals. We investigated placental phylogeny using Bayesian and maximum-likelihood methods and a 16.4-kilobase molecular data set. Interordinal relationships are almost entirely resolved. The basal split is between Afrotheria and other placentals, at about 103 million years, and may be accounted for by the separation of South America and Africa in the Cretaceous. Crown-group Eutheria may have their most recent common ancestry in the Southern Hemisphere (Gondwana).

Emerging infectious disease and the loss of biodiversity in a Neotropical amphibian community

Abstract: Pathogens rarely cause extinctions of host species, and there are few examples of a pathogen changing species richness and diversity of an ecological community by causing local extinctions across a wide range of species. We report the link between the rapid appearance of a pathogenic chytrid fungus Batrachochytrium dendrobatidis in an amphibian community at El Cope, Panama, and subsequent mass mortality and loss of amphibian biodiversity across eight families of frogs and salamanders. We describe an outbreak of chytridiomycosis in Panama and argue that this infectious disease has played an important role in amphibian population declines. The high virulence and large number of potential hosts of this emerging infectious disease threaten global amphibian diversity.