玉溪哪里做引产安全(玉溪无痛人流那好) (今日更新中)

Being home more during the pandemic, and with less traffic on the roads from stay-at-home orders, many people have heard more bird calls and the sounds of nature in urban areas. Scientists now say at least one bird species has been able to adjust their bird song because of the lack of human noise to compete with.Researchers have been studying the white-crowned sparrows in and around San Francisco for more than two decades. They compare their songs in recent years with recordings made in the 1970s.They found as traffic levels increased over the decades, the lowest frequencies of the sparrows’ song rose. This allowed their song to be heard above the low hum of vehicles. The top frequencies remained the same, so the total frequency bandwidth of their communication was narrowed.Degrading their songs this way, and limiting their range, makes them less effective at deterring rivals, attracting mates, or hearing their own chicks, according to researchers. In noisy environments, birds have to sing louder, which research has shown can result in stress and can speed up a bird’s aging and disrupt their metabolisms.When stay-at-home orders and coronavirus pandemic safety measures were put in place in March, the lead researcher, Elizabeth Derryberry, remembers seeing an image of the Golden Gate Bridge in San Francisco completely empty of cars or humans. She wondered how the sparrows were responding.They compared audio recordings of the bird songs from spring 2015 and 2016, to those taken this spring. The recordings were made in a variety of urban and rural locations around the greater San Francisco area.“We found that birds sung at lower minimum frequencies, achieving greater bandwidth songs in newly open acoustic space. An increase in frequency bandwidth results in the transmission of more information and greater vocal performance,” the study states.The samples taken in 2020 revealed the white-crowned sparrows had changed their tune, so-to-speak, and were singing softer and using a wider range of frequencies. They also were able to communicate twice as far as previous recordings.“This doubling in communication distance could elevate fitness by reducing territorial conflicts and increasing mating potential,” researchers stated.Researchers also say this explains why more people report hearing birds during the pandemic. Since the songs are traveling farther distances, humans are able to hear more of them.They also say the changes in the birds’ songs were more pronounced in urban areas compared to the rural location samples. This would make sense, they say, because the traffic noise did not change as drastically in the rural locations during the pandemic.“Our findings indicate that songbirds like white-crowned sparrows have a striking capacity to exploit newly empty soundscapes following acute but ephemeral amelioration of noise pollution, suggesting that lasting remediation might engender even more promising outcomes, such as demographic recovery and higher species diversity in urban areas,” they concluded. 3055

BONITA, Calif. (KGTV) - California Highway Patrol officers are investigating a wrong-way crash on the Eastbound lanes of Highway 54 near the 125. The crash happened just after 8 p.m. Friday and reduced traffic to one lane. All lanes reopened shortly before 11 p.m. CHP believes the driver of a red Toyota Corolla was driving the wrong way and crashed into a white BMW carrying a mother and two children. One of her children was eight years old; the other was less than a year old.RELATED:Woman critically injured in Logan Heights crashLawsuit filed over deadly wrong-way crash on I-805Mother sentenced for DUI crash that injured 3 childrenThe mother was taken to the hospital with a broken leg. The children are okay, according to the CHP. The driver of the Corolla was not wearing a seat belt and was partially ejected. He was taken to the hospital. CHP is investigating if drugs or alcohol were a factor in the crash. 927

BONSALL (CNS) - A motorcycle and a body were found in the bushes off Old River Road underneath the state Route 76 bridge Sunday.At 2:23 p.m., California Highway Patrol officers requested the San Diego County Medical Examiner to meet them at the scene of an apparent traffic collision, which may have happened earlier Sunday morning, according to a CHP incident log.The officers said the motorcycle was found about 45 feet down, in the bushes.No further information on the incident was immediately available. 515

BRUSSELS (AP) — Britain and the European Union have struck a provisional free-trade agreement that should avert New Year’s chaos for cross-border commerce and bring a measure of certainty to businesses after years of Brexit turmoil. The breakthrough on Thursday came after months of tense and often testy negotiations that whittled differences down to three key issues: fair-competition rules, mechanisms for resolving future disputes and fishing rights. In a statement from Downing Street, the Prime Minister's residence, said, "We have got Brexit done and we can now take full advantage of the fantastic opportunities available to us."Now comes the race to approve and ratify the deal before the U.K. leaves the EU’s economic structures on Jan. 1. The British and European parliaments both must hold votes on the agreement. And key aspects of the future relationship between the 27-nation bloc and its former member remain unresolved. 944

BERLIN, Pa. -- A National Guardsman is accused of making threats to kill Vice President Mike Pence before his visit to Pennsylvania for the annual observance of the Flight 93 crash. William Robert Dunbar, 22, of Berlin, Pennsylvania was charged Saturday with disorderly conduct and terroristic threats.According to a criminal complaint filed against Dunbar, he was on duty at the U.S. Army National Guard Training center in Richland Township when he said, “If someone pays me enough money, I will kill the vice president.”Witnesses said they contacted commanding officers after they heard Dunbar threaten to "kill" or "murder" the vice president on at least two separate occasions. The witnesses told police they were "fearful" of the threats Dunbar made and contacted their commanding officer immediately. Police said Dunbar was taken to Conemaugh Memorial Medical Center for evaluation and then released into the custody of Richland Police. He is being held in the county prison in lieu of 0,000 bond.  1035

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