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Natural selection and color: The devil is in the detail

Researchers have looked at a species of fish to help unravel one of the biggest mysteries in evolutionary biology.

In many species of plants and animals, individuals from the same population often come in different color variants. But the mystery has remained as to why one color doesn't eventually replace the other through natural selection.

Research published in the Journal of Evolutionary Biology has looked at a species of Central American freshwater fish to look at how different colors are maintained in the species.

Andromeda's stellar disk indicates more violent history than Milky Way

A detailed study of the motions of different stellar populations in the disk of the Andromeda galaxy has found striking differences from our own Milky Way, suggesting a more violent history of mergers with smaller galaxies in Andromeda's recent past.

The structure and internal motions of the stellar disk of a spiral galaxy hold important keys to understanding the galaxy's formation history. The Andromeda galaxy, also called M31, is the closest spiral galaxy to the Milky Way and the largest in the local group of galaxies.

Gloger's rule for animals also applies to flowers

In 1833, Constantin Wilhelm Lambert Gloger published his key observation that warm-blooded animals tend to be more heavily pigmented or darker the closer they live to the equator.

triheptanoin as therapeutic for Huntington's disease

A team of researchers has demonstrated the therapeutic potential of triheptanoin in ten patients with Huntington's disease. Derivatives of this triglyceride, with its unique composition, might be able to slow the progression of the disease by improving the energy metabolism of the brain. This research is published in the journal Neurology.

How petunias avoid self-fertilization

The ability of many plant species to recognize and their own pollen enables them to avoid inbreeding and the genetic defects that brings. Plants recognize their own pollen by a molecular mechanism, known as 'self-incompatibility' or 'SI'. Previous studies revealed that plants and animals have evolved so-called one-to-one self-recognition systems where a single male protein is capable of recognizing a single female protein which can trigger a pollen rejection response.

Soot and dirt in North American snow reveal regional patterns

Everyone who has lived in snow knows it is not as white as it looks - it's rarely white at all. Mixed in with the reflective flakes are tiny, dark particles of pollution. University of Washington scientists recently published the first large-scale survey of impurities in North American snow to see whether they might absorb enough sunlight to speed melt rates and influence climate.

The high road and the low road: following the migration path of ancient maize

After wild teosinte grass was first domesticated in southern Mexico, maize, commonly called corn, took both a high road and a coastal low road as it moved into what is now the U.S. Southwest, reports an international research team which did DNA analysis of corn cobs dating back over 4,000 years and provides the most comprehensive tracking to date of the origin and evolution of maize in the Southwest and settles a long debate over whether maize moved via an upland or coastal route into the U.S.

Algae and land plants use same molecular machinery to respond to hormone

Land-based plants respond to hormones in order to survive and it was once assumed that such hormone signaling machinery only existed in these relatively complex plants but new research shows that some types of freshwater algae can also detect ethylene gas - the same stress hormone found in land plants - and might use these signals to adapt to changing environmental conditions.

Algae blooms create their own favorable conditions

Fertilizers are known to promote the growth of toxic cyanobacterial blooms in freshwater and oceans worldwide, but a new multi-institution study shows the aquatic microbes themselves can drive nitrogen and phosphorus cycling in a combined one-two punch in lakes.

When geckos fail

A study has found that evolution can downgrade or entirely remove adaptations a species has previously acquired, such as limb loss in snakes, giving the species new survival advantages.

The researchers focused their attention on geckos, specifically the adhesive system that allows geckos to cling to surfaces. They found that species of geckos in which the adhesive system was either lost or simplified saw elevated rates of evolution related to morphology and locomotion.

Music is cultural - and cross-cultural

Whether you are a Pygmy in the Congolese rainforest or a hipster in Canada, certain aspects of music will touch you in exactly the same ways, according to a team of researchers from McGill, Technische Universität Berlin, and the University of Montreal. They arrived at this conclusion after traveling deep into the rainforest to play music to a very isolated group of people, the Mbenzélé Pygmies, who live without access to radio, television or electricity.

Why salt melts ice better than vegetable juice

Winter weather can mean treacherous driving across much of the country. Road crews spread rock salt all over the highways and byways.

Though environmentalists and the academics who give them cultural ammunition don't like salt on roads, it works a whole lot better than the expensive vegetable juice alternatives that get promoted. But why?

Humans are eroding soil 100X faster than nature

A new study has found that removing native forest and putting in farms can accelerate erosion so dramatically that in a few decades as much soil is lost as would naturally occur over thousands of years.

Had you stood on the banks of the Roanoke, Savannah, or Chattahoochee Rivers a hundred years ago, you'd have seen a lot more clay soil washing down to the sea than before European settlers began clearing trees and farming there in the 1700s. Around the world, deforestation and food productions have been blamed for increasing erosion above its natural rate.

Wave energy more dependable than other subsidized energy sources

A new analysis suggests that large-scale wave energy systems developed in the Pacific Northwest could provide steady, dependable energy and be integrated into the overall energy grid at lower costs than other forms of alternative energy, like wind power.

Fossil fuel reserves must stay in the ground to avoid dangerous climate change by 2050

A third of oil reserves, half of gas reserves and over 80% of current coal reserves globally should remain in the ground and not be used before 2050 if global warming is to stay below the 2°C target agreed by policy makers, according to new research by the UCL Institute for Sustainable Resources.

The study funded by the UK Energy Research Centre and published in Nature today, also identifies the geographic location of existing reserves that should remain unused and so sets out the regions that stand to lose most from achieving the 2°C goal.