Dry future climate could reduce orchid bee habitat

During Pleistocene era climate changes, neotropical orchid bees that relied on year-round warmth and wet weather found their habitats reduced by 30 to 50 percent, according to a Cornell University study that used computer models and genetic data to understand bee distributions during past climate changes.In previous studies, researchers have tracked male and female orchid bees and found that while females stay near their nests, male orchid bees travel, with one study concluding they roam as far as 7 kilometers per day. These past findings, corroborated by genetic data in the current study, reveal that males are more mobile than females.The study, published online in the journal Molecular Ecology, has important implications for future climate changes.”The dataset tells us that if the tendency is to have lower precipitation in combination with deforestation, the suitable habitat for the bees is going to be reduced,” said Margarita Lpez-Uribe, the paper’s first author and a graduate student at Cornell.The good news is that since male orchid bees habitually travel far, they can keep bee populations connected and healthy.”The males are mediating genetic exchange among populations, maintaining connectivity in spite of fragmentation of habitats,” said Lpez-Uribe. “This is a possible mechanism bees could use to ameliorate the negative impacts of population isolation resulting from future climate changes and deforestation.”By looking at current climate and bee distributions, Lpez-Uribe and colleagues assessed parameters of climate conditions that each of three bee species within the genus Eulaema could tolerate physiologically, including temperature and precipitation variability. She found that one of the three species, Eulaema cingulata, was three times more tolerant to a variety of climatic conditions.By proceeding with the caveat that physiological tolerance has remained constant — species tend to be evolutionarily conservative about shifting their niches — the researchers used computer models to simulate past bee distributions based on climate conditions in the Pleistocene. The results showed that in the past, during periods when the neotropics had lowered precipitation, each species experienced significant reduction in suitable habitat, with E. cingulata maintaining the largest geographical ranges.Climate and ecological niche computer model simulations were closely matched by genetic data of the two less-tolerant orchid bee species. The genetic data included mitochondrial markers, which are only inherited from females, and nuclear markers, which come from males and females. The mitochondrial DNA showed that individual bees in one geographic area were more closely related to each other than to bees from other areas. The findings suggest the maternal lines of these bees remained in the area and shared the same pools of DNA over time. But the bi-parental nuclear DNA showed more variation between individuals within an area, offering evidence that males traveled and shared their DNA with other regional groups.Orchid bees live in the neotropics, an ecozone that includes part of South and Central America, the Mexican lowlands and the Caribbean islands. …

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Fresh analysis of dinosaur skulls shows three ‘species’ are actually one

Aug. 10, 2013 — A new analysis of dinosaur fossils by University of Pennsylvania researchers has revealed that a number of specimens of the genus Psittacosaurus — once believed to represent three different species — are all members of a single species. The differences among the fossil remains that led other scientists to label them as separate species in fact arose from how the animals were buried and compressed, the study found.”Because of the vagaries of fossilization, no two fossils are the same,” said senior author Peter Dodson, professor of anatomy in Penn’s School of Veterinary Medicine and professor of paleontology in the School of Arts and Sciences’ Department of Earth and Environmental Science. “Animals are alive and they die, but what’s crucial in paleontology is what happens to the animals after they die.”The research involved a cutting-edge technique, known as three-dimensional geometric morphometrics, which uses lasers to generate data about the shape of different specimens. This is the first time the approach has been used to study dinosaur fossils and could lead to a re-examination of the taxonomic classifications of additional dinosaur species as well as other long-extinct fossil organisms.Brandon Hedrick, a doctoral student in the Department of Earth and Environmental Science, led the study in collaboration with Dodson. Their research will be reported in the journal PLOS ONE.The investigation focused on dinosaurs in the genus Psittacosaurus, a word that comes from the Greek for “parrot lizard.” The group was named for the animal’s beaked face, not unlike that of a turtle. Originally discovered in 1923, 15 species have been classified as Psittacosaurus, though a recent analysis confirmed only nine of these as definite members of the genus. These animals were small plant-eaters that lived 120 to 125 million years ago. Paleontologists have discovered Psittacosaurus fossils in Mongolia, China and Russia and possibly in Thailand.”Meat-eaters are sexy; plant-eaters are not,” Dodson said. “This isn’t a flashy dinosaur. …

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New primate species native of Madagascar, Lavasoa Dwarf Lemur, discovered

July 29, 2013 — The island of Madagascar harbors a unique biodiversity that evolved due to its long-lasting isolation from other land masses. Numerous plant and animal species are found solely on Madagascar. Lemurs, a subgroup of primates, are among the most prominent representatives of the island’s unique fauna. They are found almost exclusively on Madagascar. The only exceptions are two species of the genus Eulemur that also live on the Comoros Islands, where they probably have been introduced by humans.Thanks to extensive field research over the past decades, numerous previously unknown lemur species have been discovered. Dwarf lemurs in turn received relatively little attention to date and the diversity within this genus is still not well known. Researchers of the universities of Mainz and Antananarivo have investigated lemur populations in southern Madagascar. Based on fieldwork and laboratory analyses, they now identified a previously unknown species of dwarf lemur. The findings of the research project have recently been published in the journal Molecular Phylogenetics and Evolution.”Together with Malagasy scientists, we have been studying the diversity of lemurs for several years now,” said Dr. Andreas Hapke of the Institute of Anthropology at Johannes Gutenberg University Mainz (JGU). …

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The jewels of the ocean: Two new species and a new genus of octocorals from the Pacific

June 3, 2013 — The flora and fauna of the American west coast is generally believed to be well explored and studied. However, a new study and a taxonomic assessment of the octocorals from the north eastern Pacific Ocean proves such assumptions wrong, with two new beautiful and colourful species of soft corals alongside a new genus.Share This:The study was published in the open access journal Zookeys.”It is remarkable that in a region previously thought to be as familiar and well known as the west coast of North America — with its numerous large urban centers and major marine laboratories — revisionary systematics are not only still possible, but essential for our understanding of global biodiversity,” comments the author of the study Dr Williams, California Academy of Sciences.The paper describes four aspects of the North American west coast fauna, such as a new species of pale orange stoloniferous soft coral from San Diego, California. Also included is a revisionary assessment of a well-known soft coral previously misidentified as Gersemia rubiformis from the Pacific Northwest. Another new species of the soft coral Gersemia from the coast of British Columbia, Canada has been also described. This new species is found in colonies with beautiful pink to reddish coloration in life.The study also defines a new genus named for a species previously placed in a tropical Indo-Pacific genus for the past century. The species for which the genus was erected inhabits the Gulf of the Farallones National Marine Sanctuary near San Francisco, California, as well as several other localities on the Pacific Coast. The remarkable diversity of octocorals accounts for around 3400 species described worldwide. Although the majority of octocoral taxa was described in the 19th and early 20th centuries, much of this colourful marine fauna is in fact only minimally studied and continues to surprise with new discoveries nowadays.Share this story on Facebook, Twitter, and Google:Other social bookmarking and sharing tools:|Story Source: The above story is reprinted from materials provided by Pensoft Publishers. The original story is licensed under a Creative Commons License. Note: Materials may be edited for content and length. …

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