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Comment by Dr. Krishna Kumari Challa on August 9, 2014 at 9:21am

Two species of birds — carrion crows, which predominate in western Germany, and the closely related hooded crows that prevail further to the east, in Sweden and Poland can mate with each other, but they look very different — carrion crows are black, and hooded crows have black-and-gray bodies — and the birds strongly prefer mates of their own kind. For a long as anyone can remember, the two groups have remained distinct, save for a narrow band of habitat stretching from Denmark through eastern Germany to northern Italy where they sometimes intermingle.

The crows present a puzzling question to biologists, which gets to the heart of what it means to be a species: Given that hooded and carrion crows can mate and swap genes, how do the two groups maintain their individual identities? It’s as if you mixed red and yellow paint in a bucket but the two colors stubbornly refused to make orange.

In new research published in June in the journal Science, Wolf’s ( an Evolutionary Biologist) team has found that a surprisingly small chunk of DNA may hold the answer. A comparison of the carrion and hooded-crow genomes showed that the sequences are almost identical. Differences in just 82 DNA letters, out of a total of about 1.2 billion, appear to separate the two groups. Almost all of them are clustered in a small part of one chromosome. “Maybe just a few genes make a species what they are,” said Chris Jiggins, a biologist at the University of Cambridge in England, who was not involved in the study. “Maybe the rest of genome can flow, so species are much more fluid than we imagined before.”

The findings are striking because they suggest that just a few genes can keep two populations apart. Something within that segment of DNA stops black crows from mating with gray ones and vice versa, creating a tenuous mating barrier that could represent one of the earliest steps in the formation of new species. “They look very different and prefer to mate with their own kind, and all of that must be controlled by these narrow regions,” Jiggins said.
http://www.ncbi.nlm.nih.gov/pubmed/24948738
http://www.simonsfoundation.org/quanta/20140805-as-animals-mingle-a...

Crows aren’t alone in their behavio

Comment by Dr. Krishna Kumari Challa on August 9, 2014 at 6:04am

MIT creates magnetic microhair that lets water defy gravity

Researchers have created an elastic material bristling with microscopic strands of nickel that can direct the flow of liquids and light.

Comment by Dr. Krishna Kumari Challa on August 8, 2014 at 6:40am

Why Can’t You Remember Being a Baby?
The fast growth of young brains may come at the expense of infant memories
The results of a study , published in May in the journal Science, neuro-scientists Frankland and Josselyn think that rapid neuron growth during early childhood disrupts the brain circuitry that stores old memories, making them inaccessible. Young children also have an underdeveloped prefrontal cortex, another region of the brain that encodes memories, so infantile amnesia may be a combination of these two factors.

Comment by Dr. Krishna Kumari Challa on August 8, 2014 at 5:20am

Bugs that can co-operate best with each other are most likely to be able to infect new species, including humans, a new study has found.

Scientists have discovered that bacteria co-operate with each other when causing infection, a finding that may help identify animal diseases that transmit to people such as anthrax and the superbug MRSA.

Bacteria interact by releasing molecules to help them adapt to their environment - for example, when killing competing infections in their victim. They co-ordinate these actions by releasing tiny amounts of chemicals as signals.

Bacteria that can co-operate to create an environment in which they can thrive are potentially able to infect lots of different species, including humans, researchers said.

Discovering why some diseases are better equipped to infect more species than others - and therefore could affect humans - could be valuable in predicting and managing health threats.

Most new human infections arise from diseases that transmit from animals to humans. Many of these cause serious infections and are difficult to control, such as anthrax and the superbug MRSA.

Research led by the University of Edinburgh used a combination of mathematical models and scientific analysis of genetic code in almost 200 types of bacteria.

They found that those bugs that carry lots of genes that help them to co-operate are best equipped to adapt to various environments.

"Humans have been able to colonise almost all of their planet by collectively modifying the environment to suit themselves. Our study shows bugs try to do the same - co-operation is important for the spread of bacteria to new species," Dr Luke McNally of the University of Edinburgh' School of Biological Sciences, who led the study, said.

The study was published in the journal Nature Communications.

Comment by Dr. Krishna Kumari Challa on August 8, 2014 at 5:19am

Scientists turn a brown butterfly purple—in just six generations
Structural and pigment changes combine to turn brown into purple.
The results show that, although the individual structures are tiny and delicate, the butterfly's wing as a whole is remarkably robust and can easily undergo rearrangements that radically change its optical properties. In fact, as the authors point out, a bit of variability in these properties appears to be a normal part of the genetic background of these species. This natural variability means that evolution doesn't have to wait for a fortunate mutation to get to work.
http://arstechnica.com/science/2014/08/scientists-turn-a-brown-butt...

Comment by Dr. Krishna Kumari Challa on August 8, 2014 at 5:14am

Unmanned aerial vehicles or drones will soon fly over India's forests to monitor poaching, track wildlife and even count the population of tigers.

Scientists at the Wildlife Institute of India (WII) are coming up with a series of such drones which are being customised indigenously to suit different types of forest landscape.
Under a joint collaboration with the National Tiger Conservation Authority (NTCA) and international environment body WWF, they are preparing a detailed project report for introducing drone monitoring in 10 wildlife-rich areas across the country.

The primary objectives of these drones would be to track the movements of wildlife and monitor poaching.

They may also be used in counting the population of animals like tiger.
A drone can be put on autopilot mode and sent as far as 40-50 km deep into the forest where it can record images and videos and transmit them on a realtime basis. Its movement can also be controlled through a GPS-based system.

Such drones were recently tested successfully in Panna Tiger Reserve and Kaziranga.
Drones can also be used for night surveillance and tracking of many elusive and shy animals like the red panda and snow leopard, which are very rarely seen by the human eye in their natural wild habitat.

Travelling at a speed of 40 -100km per hour, the drones can be used for around 40-50 minutes.

Comment by Dr. Krishna Kumari Challa on August 7, 2014 at 5:57am

Comment by Dr. Krishna Kumari Challa on August 6, 2014 at 9:21am

Elderly patients could benefit from pretreatment with imiquimod before seasonal influenza vaccination.
Scientists have found that treating elderly patients with imiquimod before immunizing them against influenza improved the protective effects of the vaccine. This study has been published in the journal Clinical Infectious Diseases.
In a study, a team led by Professor Yuen Kwok-yung, Chair Professor of Department of Microbiology, Li Ka Shing Faculty of Medicine of The University of Hong Kong (HKU) has discovered a simple and practical way of protecting elderly patients with medical illness from seasonal influenza. By applying the Toll-like receptor 7 agonist imiquimod before intradermal injection, the protection by flu vaccine is enhanced, thus decreasing the risk of hospitalization. Imiquimod is a safe immune-stimulatory drug, which has used topically to treat skin warts for many years.
http://cid.oxfordjournals.org/content/early/2014/07/20/cid.ciu582

Comment by Dr. Krishna Kumari Challa on August 6, 2014 at 9:18am

Himalayas ‘Too Seismic’ For Big Dams
Scientists have raised concerns that the ambitious dam projects planned in the Himalayan region do not adequately account for seismic activity
http://www.currentscience.ac.in/Volumes/106/12/1658.p

Comment by Dr. Krishna Kumari Challa on August 6, 2014 at 9:12am

Prof Sir Alec Jeffreys, who discovered DNA fingerprinting, win's the world’s oldest science prize
The man who discovered DNA fingerprinting has won the world's oldest science prize — Royal Society's Copley Medal.

In 1984, Prof Sir Alec Jeffreys stumbled on a method for distinguishing individuals based on their DNA. It was a discovery that went on to transform forensic science and resolve questions of identity and kinship.

He received the medal "for his pioneering work on variation and mutation in the human genome".

The Copley medal was first awarded by the Royal Society in 1731, 170 years before the first Nobel Prize. It is awarded for outstanding achievements in scientific research and has been awarded to eminent scientists such as Charles Darwin, Michael Faraday, Albert Einstein and Stephen Hawking.

In 1984 Jeffreys discovered a method of showing the variation between individuals' DNA, a technique which he developed and became known as genetic fingerprinting.

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