Activity of 40 genes differs in butterflies that stay put versus those that travel south.
Come fall, monarch butterflies feel the need for a change in latitude. A new study shows that changes in the activity of a suite of genes in the butterflies' brains help the insects find their way to overwintering grounds in Mexico.
Steven Reppert, a neurobiologist from the University of Massachusetts Medical School in Worcester, leads a team of scientists on a mission to uncover the monarch's migratory signals. The team describes a new genetic analysis of stationary summer monarchs and fall migratory monarchs in the March 31 BMC Biology.
At least 40 genes are involved in keeping the monarchs Mexico-bound once they start migrating, the researchers report. Reppert and his colleagues analyzed 9,000 of the monarch butterfly's genes, about half of the genes in its genome.
Each fall, hundreds of millions of monarchs in the eastern United States and Canada begin flying south for the winter. The butterflies navigate with internal clocks and use the sun as a compass to find their way to overwintering grounds in oyamel fir forests in central Mexico. No one knows what environmental signals flip the switch that causes butterflies to forgo reproduction and start migrating.
Earth Changes
A small earthquake that rattled parts of the Bay Area Monday morning occurred on a previously unknown fault, according to Jack Boatwright, a geophysicist with the U.S. Geological Survey.
The magnitude 4.3 quake hit at 10:40 a.m. and was centered about 11 miles north of Morgan Hill and 16 miles east-southeast of San Jose, according to the USGS.
Personnel at several police departments and the USGS said they had not received reports of any damage. The trembling was felt mildly by residents in various parts of the Bay Area, including in San Francisco.
Boatwright said the small, unmapped fault that appears to have produced the earthquake is believed to be a "splay fault" off the Calaveras Fault, which is itself a branch off the San Andreas Fault. The fault crosses the hills east of San Jose, an area that is difficult to map.
The magnitude 4.3 quake hit at 10:40 a.m. and was centered about 11 miles north of Morgan Hill and 16 miles east-southeast of San Jose, according to the USGS.
Personnel at several police departments and the USGS said they had not received reports of any damage. The trembling was felt mildly by residents in various parts of the Bay Area, including in San Francisco.
Boatwright said the small, unmapped fault that appears to have produced the earthquake is believed to be a "splay fault" off the Calaveras Fault, which is itself a branch off the San Andreas Fault. The fault crosses the hills east of San Jose, an area that is difficult to map.
The U.S. Geological Survey confirms that East Tennessee was rocked by its second small earthquake in four days over the weekend.
The most recent quake happened at 2:52 PM on Sunday in Bradley County and had a magnitude of 1.3.
USGS officials say its epicenter was located six miles north of Cleveland, in an open field along Eureka Road. The exact location of the quake was about 10 miles underground.
The most recent quake happened at 2:52 PM on Sunday in Bradley County and had a magnitude of 1.3.
USGS officials say its epicenter was located six miles north of Cleveland, in an open field along Eureka Road. The exact location of the quake was about 10 miles underground.
© Ahmadi Nastaran
Travellers caught by surprise in the untimely snow storm
Travellers caught by surprise in the untimely snow storm
When snow begins to melt, people count it as a sure sign of the coming spring. With the Iranian New Year celebrated on March 21 to signal the first day of spring and to mark the revival of nature, many Iranians pack their bags and spend their holidays traveling.
This year, forcing many to cut back on their holidays and shocking many others trapped in roads, 10 to 20 centimeters of snow has blanketed the western part of the country.
© Unknown
A house is surrounded by flood water from the Red River in Fargo.
A house is surrounded by flood water from the Red River in Fargo.
After the level of the Red River inched downward throughout Sunday and Monday, there was hope that the damage caused by the rising tide was over. An early spring snowstorm, however, has swept into the area, prompting officials to think otherwise.
The river is expected to crest at nearly 12 meters, very close to the top of the city's main dike. Winds of 40 to 65 kilometers per hour are hampering emergency efforts
Last December, the Australian lemuroid ringtail possum was widely reported as the first possible extinction casualty of climate change.
But last week it rose from the dead with ecologists reporting the discovery of three of the creatures and declaring that the species was never feared extinct. But its future is far from certain.
"They have a very limited range - most likely due to an inability to tolerate high temperatures - so they are at risk from future temperature extremes," says ecophysiologist Andrew Krockenberger of James Cook University in Cairns, Australia.
Stephen Williams of James Cook University in Townsville agrees. "There has been a massive decline in one population. One more hot summer could wipe [that population] out."
But last week it rose from the dead with ecologists reporting the discovery of three of the creatures and declaring that the species was never feared extinct. But its future is far from certain.
"They have a very limited range - most likely due to an inability to tolerate high temperatures - so they are at risk from future temperature extremes," says ecophysiologist Andrew Krockenberger of James Cook University in Cairns, Australia.
Stephen Williams of James Cook University in Townsville agrees. "There has been a massive decline in one population. One more hot summer could wipe [that population] out."
© Unknown
Stingers rising up from the deep
Stingers rising up from the deep
The 'rise of slime' is coming unless we halt the threatened collapse of marine ecosystems, the Ulster Wildlife Trust said.
Seafloor habitats are being destroyed by overfishing, rising water temperatures and dwindling marine biodiversity, reducing the ability of the seas around Ireland to recover and support humans long-term, the Trust said.
Southern African countries have been hit by the worst floods in years, killing more than 100 people and displacing thousands, as a tropical storm threatened to bring more pain on Saturday.
As Mozambique braced for the arrival of a strengthening tropical storm Izilda, record river levels across the region threatened to exacerbate floods which have already affected hundreds of thousands of people.
Namibia's government declared a state of emergency last week in areas where floods have affected over 350,000 people, 13,000 of whom were displaced, according to numbers released by the United Nations on Friday.
As Mozambique braced for the arrival of a strengthening tropical storm Izilda, record river levels across the region threatened to exacerbate floods which have already affected hundreds of thousands of people.
Namibia's government declared a state of emergency last week in areas where floods have affected over 350,000 people, 13,000 of whom were displaced, according to numbers released by the United Nations on Friday.
A moderate earthquake rattled parts of Silicon Valley Monday, but there were no immediate reports of damage.
The U.S. Geological Survey said the temblor had a preliminary magnitude of 4.3 and struck at about 10:40 a.m. PDT. It was centered 11 miles north of the city of Morgan Hill, or about 16 miles southeast of San Jose.
The U.S. Geological Survey said the temblor had a preliminary magnitude of 4.3 and struck at about 10:40 a.m. PDT. It was centered 11 miles north of the city of Morgan Hill, or about 16 miles southeast of San Jose.
A strong 6.0-magnitude earthquake shook Indonesia's Papua region early Sunday, the US Geological Survey said.
The quake, which hit at 2:59 am (1759 GMT Saturday), was centred 135 kilometres (85 miles) southwest of the Papuan provincial capital of Jayapura at a depth of 53 kilometres, the USGS was quoted by AFP as saying.
There were no immediate reports of casualties or damage.
The Indonesian archipelago sits on the so-called Pacific Ring of Fire where continental plates meet, causing frequent seismic and volcanic activity.
The quake, which hit at 2:59 am (1759 GMT Saturday), was centred 135 kilometres (85 miles) southwest of the Papuan provincial capital of Jayapura at a depth of 53 kilometres, the USGS was quoted by AFP as saying.
There were no immediate reports of casualties or damage.
The Indonesian archipelago sits on the so-called Pacific Ring of Fire where continental plates meet, causing frequent seismic and volcanic activity.
