Researchers discovered a legless lizard and a tiny woodpecker along with 12 other suspected new species in Brazil’s Cerrado, one of the world’s 34 biodiversity conservation hotspots.

The Cerrado’s wooded grassland once covered an area half the size of Europe, but is now being converted to cropland and ranchland at twice the rate of the neighboring Amazon rainforest, resulting in the loss of native vegetation and unique species.

An expedition comprising scientists from Conservation International (CI) and Brazilian universities found 14 species believed new to science — eight fish, three reptiles, one amphibian, one mammal, and one bird — in and around the Serra Geral do Tocantins Ecological Station, a 716,000-hectare (1,769,274-acre) protected area that is the Cerrado’s second largest.

The lizard, of the Bachia genus, resembles a snake due to its lack of legs and pointed snout, which help it move across the predominantly sandy soil formed by the natural erosion of the escarpments of the Serra Geral. Other suspected new species include a dwarf woodpecker (genus Picumnus) and horned toad (genus Proceratophrys).

“It’s very exciting to find new species and data on the richness, abundance, and distribution of wildlife in one of the most extensive, complex, and unknown regions of the Cerrado,” said CI biologist Cristiano Nogueira, the expedition leader. “Protected areas such as the Ecological Station are home to some of the last remaining healthy ecosystems in a region increasingly threatened by urban growth and mechanized agriculture.”

The team also recorded several threatened species such as the hyacinth macaw, marsh deer, three-banded armadillo (tatu-bola), the Brazilian merganser, and the dwarf tinamou among more than 440 species of vertebrates documented during the 29-day field expedition.

Comprising 21 percent of Brazil, the Cerrado is the most extensive woodland-savanna in South America. Large mammals such as the giant anteater, giant armadillo, jaguar and maned wolf struggle to survive in the fast-changing habitat also know as Brazil’s breadbasket.

The expedition included 26 researchers from the University of São Paulo and its Museum of Zoology; the federal universities of São Carlos and Tocantins; and CI-Brazil. It was funded by the O Boticário Foundation for Conservation of Nature, with the support of the NGO Pequi–Pesquisa e Conservação do Cerrado (Research & Conservation of the Cerrado).

“The geographic distribution of some of the species registered is restricted to the area of the ecological station; thus their survival depends on the good management of the protected area and its immediate surroundings,” said Luís Fabio Silveira, of the Department of Zoology of the University of São Paulo. “From the survey we can obtain data concerning the anatomy, reproductive biology, life cycle, and distribution of the species, all of which help us in future conservation programs.”

Final results of the study, including the formal description of new species, will be used to support the development of a management plan for the Ecological Station, which was created in 2001.

“We need to know our protected areas better, especially the ecological stations whose principal objective is to generate scientific knowledge of Brazilian biodiversity, so little studied and already so severely threatened,” Nogueira said. “Unfortunately, extensive areas of the Cerrado, like the Ecological Station, are becoming increasingly rare, thus making the data collected even more important. Above all, it is necessary to know to conserve.”

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A team of scientists from Princeton University has found that one of the most intriguing phenomena in condensed-matter physics — known as the quantum Hall effect — can occur in nature in a way that no one has ever before seen.

Writing in the April 24 issue of Nature, the scientists report that they have recorded this exotic behavior of electrons in a bulk crystal of bismuth-antimony without any external magnetic field being present. The work, while significant in a fundamental way, could also lead to advances in new kinds of fast quantum or “spintronic” computing devices, of potential use in future electronic technologies, the authors said.

“We had the right tool and the right set of ideas,” said Zahid Hasan, an assistant professor of physics who led the research and propelled X-ray photons at the surface of the crystal to find the effect. The team used a high-energy, accelerator-based technique called “synchrotron photo-electron spectroscopy.”

And, Hasan added, “We had the right material.”

The quantum Hall effect has only been seen previously in atomically thin layers of semiconductors in the presence of a very high applied magnetic field. In exploring new realms and subjecting materials to extreme conditions, the scientists are seeking to enrich the basis for understanding how electrons move.

Robert Cava, the Russell Wellman Moore Professor of Chemistry and a co-author on the paper, worked with members of his team to produce the crystal in his lab over many months of trial-and-error. “This is one of those wonderful examples in science of an intense, extended collaboration between scientists in different fields,” said Cava, also chair of the Department of Chemistry.

“This remarkable experiment is a major home run for the Princeton team,” said Phuan Ong, a Princeton professor of physics who was not involved in the research. Ong, who also serves as assistant director of the Princeton Center for Complex Materials, added that the experiment “will spark a worldwide scramble to understand the new states and a major program to manipulate them for new electronic applications.”

Electrons, which are electrically charged particles, behave in a magnetic field, as some scientists have put it, like a cloud of mosquitoes in a crosswind. In a material that conducts electricity, like copper, the magnetic “wind” pushes the electrons to the edges. An electrical voltage rises in the direction of this wind — at right angles to the direction of the current flow. Edwin Hall discovered this unexpected phenomenon, which came to be known as the Hall effect, in 1879. The Hall effect has become a standard tool for assessing charge in electrical materials in physics labs worldwide.

In 1980, the German physicist Klaus von Klitzing studied the Hall effect with new tools. He enclosed the electrons in an atom-thin layer, and cooled them to near absolute zero in very powerful magnetic fields. With the electrons forced to move in a plane, the Hall effect, he found, changed in discrete steps, meaning that the voltage increased in chunks, rather than increasing bit by bit as it was expected to. Electrons, he found, act unpredictably when grouped together. His work won him the Nobel Prize in physics in 1985.

Daniel Tsui (now at Princeton) and Horst Stormer of Bell Laboratories did similar experiments, shortly after von Klitzing’s. They used extremely pure semiconductor layers cooled to near absolute zero and subjected the material to the world’s strongest magnet. In 1982, they suddenly saw something new. The electrons in the atom-thin layer seemed to “cooperate” and work together to form what scientists call a “quantum fluid,” an extremely rare situation where electrons act identically, in lock-step, more like soup than as individually spinning units.

After a year of thinking, Robert Laughlin, now at Stanford University, devised a model that resembled a storm at sea in which the force of the magnetic wind and the electrons of this “quantum fluid” created new phenomena — eddies and waves — without being changed themselves. Simply put, he showed that the electrons in a powerful magnetic field condensed to form this quantum fluid related to the quantum fluids that occur in superconductivity and in liquid helium.

For their efforts, Tsui, Stormer and Laughlin won the Nobel Prize in physics in 1998.

Recently, theorist Charles Kane and his team at the University of Pennsylvania, building upon a model proposed by Duncan Haldane of Princeton, predicted that electrons should be able to form a Hall-like quantum fluid even in the absence of an externally applied magnetic field, in special materials where certain conditions of the electron orbit and the spinning direction are met. The electrons in these special materials are expected to generate their own internal magnetic field when they are traveling near the speed of light and are subject to the laws of relativity.

In search of that exotic electron behavior, Hasan’s team decided to go beyond the conventional tools for measuring quantum Hall effects. They took the bulk three-dimensional crystal of bismuth-antimony, zapped it with ultra-fast X-ray photons and watched as the electrons jumped out. By fine-tuning the X-rays, they could directly take pictures of the dancing patterns of the electrons on the edges of the sample. The nature of the quantum Hall behavior in the bulk of the material was then identified by analyzing the unique dancing patterns observed on the surface of the material in their experiments.

Kane, the Penn theorist, views the Princeton work as extremely significant. “This experiment opens the door to a wide range of further studies,” he said.

The images observed by the Princeton group provide the first direct evidence for quantum Hall-like behavior without external magnetic fields.

“What is exciting about this new method of looking at the quantum Hall-like behavior is that one can directly image the electrons on the edges of the sample, which was never done before,” said Hasan. “This very direct look opens up a wide range of future possibilities for fundamental research opportunities into the quantum Hall behavior of matter.”

Other researchers on the paper include graduate students David Hsieh, Andrew Lewis Wray, YuQi Xia and postdoctoral fellows Dong Qian and Yew San Hor. The team members are in the departments of physics and chemistry, and are members of the Princeton Center for Complex Materials. They used facilities at the Lawrence Berkeley Laboratory in Berkeley, Calif., and the University of Wisconsin’s Synchrotron Radiation Center in Stoughton, Wis.

This work was supported by U.S. Department of Energy and the National Science Foundation.

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The Centre for Addiction and Mental Health (CAMH) has discovered a new form of intellectual disability involving mental retardation (MR) along with the eye defect retinitis pigmentosa (RP). CAMH also discovered the previously unidentified gene that causes this disorder, CC2D2A. This scientific advance will help understand the developmental and biological processes involved in brain development, and may help identify ways to diagnose and treat intellectual disabilities.

Under the direction of Dr. John Vincent, scientist at CAMH, the team identified a mutation in CC2D2A that causes the production of a shortened protein missing the C2, or calcium-binding, domain. This protein mutation results in faulty cell function, which leads to MR with RP.

Most genes for intellectual disabilities that have been found so far are on the X chromosome. As Dr. Vincent explains, this mutation was found on the autosome (The 22 pairs of non-sex chromosomes, that make up the 46 chromosomes in the human body). Autosomal-recessive inheritance (where both mother and father carry a gene mutation on one chromosome, but both maternal and paternal copies must be passed on to the offspring to cause the disorder) is believed to be relatively common in intellectual disability, though only four genes causing this type of disability have been identified to date.

“What’s really exciting is that the new gene, CC2D2A, encodes a protein with domains similar to those found in one of the previous four autosomal recessive MR genes. This link could suggest a common function that is essential for normal brain development,” says Dr. Vincent.

Dr. Vincent and his team will continue exploring these initial findings, to help identify more people with mutations affecting the CC2D2A gene. This additional research will provide scientists more clues to understand, diagnose and treat intellectual disabilities.

Intellectual disabilities, also known as developmental delay or mental retardation, are a group of disorders defined by deficits in cognitive and adaptive development. Impacting between one and three percent of the population, a higher proportion of men are affected by this type of disability.

A full copy of the this paper, published in The American Journal of Human Genetics, is available under the title “CC2D2A, Encoding A Coiled-Coil and C2 Domain Protein, Causes Autosomal-Recessive Mental Retardation with Retinitis Pigmentosa”.

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