【828-830】委内瑞拉士兵选择沙漠&印度称对巴基斯坦激进分子营地进行了空袭?&斑马为什么有条纹？
AS IT IS
Why Do Zebras Have Stripes?
February 26, 2019
Scientists have provided new evidence to help solve one of the world’s oldest mysteries: why does a zebra have stripes? It appears that all those lines cause problems for insects and makes it very hard for them to land on the animal.
Researchers recently described experiments showing that horse flies have a difficult time landing on zebras while easily landing on horses of a single color.
In one experiment, the researchers put blankets with stripes on horses and saw that fewer flies landed on them. They “fly past them or …bump into them and bounce off,” said Tim Caro of the University of California-Davis. He was the lead writer of a report on the study. The report was published in the journal PLOS ONE.
Closely related to horses, the world’s three zebra species are known for their black-and-white striped bodies.
Zebras are native to Africa’s savannas, or grasslands. The design and appearance of the stripes is different from one zebra to the next. No two zebras are alike.
There had been four main theories about the reasons zebras developed stripes. The first theory is to avoid attack by meat-eating animals. Another is so that zebras have an easier time recognizing other zebras. A third idea is thermoregulation. That is the ability of a creature to control its body temperature, even when the surrounding temperature is different. The fourth theory is to prevent attacks by biting flies.
“Only the last stands up…” Caro said. “Most biologists involved with research on mammal coloration accept that this is the reason that zebras have stripes.”
African horse flies carry diseases, such as trypanosomiasis. The sickness can cause wasting and be deadly.
The researchers recorded videos of horse flies as they tried to bite zebras and horses at a farm in North Somerset, England. Stripes did not stop flies from a distance, as they circled horses and zebras at similar rates. But the flies were 25 percent less likely to land on zebras.
University of Bristol biologist Martin How worked with Caro on the study. He said stripes may confuse flies when they get too close to zebras.
“In addition to stripes that prevent controlled landings by horse flies, zebras are always moving their tail and may frighten off the horse flies if they do land successfully,” How said. He added that zebras are also using behavioral means to prevent flies from biting them.
I’m Susan Shand.
The Associated Press reported this story. Susan Shand adapted the AP reports for VOA Learning English. George Grow was the editor.
Write to us in the Comments Section or on our Facebook page.
_______________________________________________________________
Words in This Story
mammal – n.a type of animal that feeds milk to its young and that usually has hair or fur covering most of its skin
confuse– v.to cloud; to make something more complex; to identify wrongly
species– n.a classification or grouping of living organisms
stripe– n.a long line that is different in color from nearby areas
blanket– n.a large covering
AS IT IS
India Says It Carried Out Air Strike on Militant Camp in Pakistan
February 26, 2019
India is claiming responsibility for air strikes on Pakistani territory.
India says the attack targeted a camp of the Islamist militant group Jaish-e-Mohammad. The group took responsibility for a suicide bombing in Indian Kashmir earlier this month. The explosion killed 30 paramilitary troops.
India says many militants died in the air strikes on Tuesday. The strikes will increase military tensions between India and Pakistan. Pakistani officials claim the attack caused no damage or injuries.
In a statement, Indian foreign secretary Vijay Gokhale called the attack a “pre-emptive strike.” He also said he had reasonable intelligence that the Jaish-e-Mohammed was planning another suicide terror attack in India.
The foreign secretary said his country struck the group’s biggest training center at Balakot, in Pakistan. “In this operation, a very large number of Jaish-e-Mohammed terrorists, trainers, (and) senior commanders,” were killed, he said.
Gokhale added that India had taken steps to avoid civilian deaths and injuries.
In Pakistan, Prime Minister Imran Khan called an emergency meeting of his national security committee on Tuesday. After the meeting, his office released a statement. It said that the strike was a political move because India is in an “election environment.”
The statement added that India’s claims were “fictitious.” It said local and international media were being taken to the area so they could see it was not a militant camp.
Major General Asif Ghafoor, a Pakistani spokesman, denied India’s description of the attack. In a statement on Twitter, he said, “Indian aircrafts…(faced) timely and effective response from Pakistan Air Force.” He added that there were no deaths or damage from the attack.
Observers said this is the first air strike launched across the line of control in Kashmir since the two countries fought a war in 1971.
Indian forces and air defenses have been put on high alert while waiting for possible reaction by Pakistan. Pakistan has warned it will answer any military action by India. There has been a large Pakistani troop buildup in Indian Kashmir in recent days.
The Indian foreign secretary repeated his country’s calls on Pakistan to take action against militants operating on its territory. He said Pakistan should take action to remove Jaish-e-Mohammed camps and arrest terrorists.
Pakistan has long denied that it gives assistance to militant groups that target Kashmir.
The deadly car bombing in Indian Kashmir led to widespread anger in India and calls for action. Indian Prime Minister Narendra Modi had promised a strong responseand said the armed forces had been given the freedom to take action.
The targeting of militant camps is a change from India’s years-old policy of restraint. The militant groups are fighting for either Kashmir’s independence or to join Pakistan.
The military action follows a diplomatic attempt by India to isolate Pakistan from other countries for its suspected support to militant groups. The Himalayan territory is divided between the two countries and has been the cause of two of their three wars.
VOA’s Anjana Pasricha reported this story. Susan Shand adapted her report for VOA Learning English. George Grow was the editor.
Write to us in the Comments Section or on our Facebook page.
___________________________________________________________
Words in This Story
pre-emptive – adj. done to stop an unwanted act by another group or country from happening
fictitious – adj. not true or real
alert – n. to give (someone) important information about a possible problem or danger
response – n. an answer; something spoken, written or done in reaction to something else
isolate – v. to put or keep (someone or something) in a place or situation that is separate from others
AS IT IS
Venezuelan Soldiers Choose to Desert
February 26, 2019
Colombia Venezuela Political Crisis
A Venezuelan opposition plan failed to bring humanitarian aid into the country Saturday.
Soldiers loyal to President Nicolas Maduro refused to let the trucks carrying food and medical supplies cross the border from Colombia. Many of Venezuela’s National Guard then made the decision to flee the military and their country for Colombia. Immigration officials there said that more than 320 soldiers have sought shelter in Colombia since Saturday.
Many of the military dissenters ended up in a shelter run by a Catholic religious worker. There, they can find information about family members back home. The former soldiers are also learning how to request for asylum.
Nine of them spoke with the Associated Press. They described the day they were ordered by commanders to stop aid from entering Venezuela. Many feared they would be placed in jail. So, they obeyed their orders and fired tear gas at protesters. Two soldiers said they were part of the failed aid transport plot.
The soldiers’ escape comes as the Venezuelan opposition pressures the military to accept Juan Guaidó as the nation’s true president. More than 50 nations -- including the United States and many Latin American countries -- have recognized Guaidó as such.
But top military officials have stood by Maduro, who has shown no sign that he will surrender power.
The soldiers who fled say within the military, breaking from Maduro is almost impossible. The Venezuelan army includes at least 200,000 troops.
Severe shortages of food and medicine in the last few years have led more than 3 million people to leave Venezuela
When Guaidó first announced the aid push, Jorge Torres said he and three other soldiers began to form a plan. As National Guard drivers, they had access to armored trucks. They planned to drive the vehicles across the Simon Bolivar International Bridge, break down the barriers that stood in the way and permit opposition trucks to carry the aid in.
Saturday morning, Torres climbed into one of the trucks and drove it across the bridge. He broke through several barriers, but also hit a woman trying to enter Colombia. She escaped serious injury, but he was forced to stop.
Torres raised his arms in surrender and helped the woman toward a hospital emergency vehicle. He was quickly taken and presented to Guaidó, who secretly came across the border into Colombia to lead the aid launch.
Torres said he stood at attention and promised his loyalty to Guaidó. “We’re still in time to change history,” he said Guaidó told him.
Many of the soldiers said they worry their wives and children will now face problems. They are also concerned about finances. Many soldiers who have fled in the last year have had difficulty getting work. They end up making a little money selling food on the streets.
Almost all the soldiers who left would support a foreign intervention in Venezuela and join in the fight.
Guaidó called on the international community Saturday to consider all possible actions to resolve Venezuela’s crisis. The conflict over the aid shipments caused four deaths and injured 300 other people.
Several of the dissenters said they believe the best way forward is for more troops to leave and help form a resistance from outside. Some say Venezuelans alone should lead such efforts. Others believe resistance requires the help of an international coalition.
All said they do not see themselves as dissenters, but as troops set on restoring Venezuela’s democracy.
“We’re going to change history,” Torres said. “We are history.”
I’m Jonathan Evans.
Christine Armario reported this story for the Associated Press. Jonathan Evans adapted it for Learning English. Caty Weaver was the editor.
______________________________________________________________
Words in this Story
access – n. a way of getting near, at, or to something or someone