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[00:00.04]Should we fear an invasion from outer space?
[00:07.32]Researchers have been searching and listening for life on other planets. 
[00:12.32]They say we should not be concerned about alien beings any time soon. 
[00:18.60]Michael Garrett teaches at the University of Leiden. 
[00:23.05]He is also the General and Scientific Director 
[00:26.48]of the Netherlands Institute for Radio Astronomy. 
[00:30.36]Professor Garrett has been listening for radio signals from other planets, 
[00:35.28]searching for signs of extraterrestrial life. 
[00:39.20]He says advanced civilizations are either rare or do not exist 
[00:45.97]in the areas of outer space he has examined. 
[00:49.72]He adds that natural processes are most likely responsible 
[00:54.72]for any radio signals that have been received on Earth.  
[00:58.96]He says that means "we can all sleep safely in our beds tonight. 
[01:04.36]An alien invasion doesn't seem at all likely."
[01:08.58]
[01:13.64]German researchers say they have discovered that some birds, 
[01:18.32]like humans, can be choosy when deciding on a possible mate.
[01:23.72]The researchers work at the Max Planck Institute for Ornithology. 
[01:28.52]They performed experiments with Zebra Finch. 
[01:32.12]They let groups of 20 female Zebra Finches 
[01:36.00]freely choose their mate from among 20 males. 
[01:40.36]Half of the resulting pairs were permitted to produce baby birds. 
[01:46.12]The researchers split up the other couples 
[01:49.04]and gave them a mate that the birds had not chosen themselves. 
[01:53.36]The study found that the finch couples that chose one another 
[01:57.16]produced many more babies than those that were forced together. 
[02:02.32]
[02:06.04]There are many good reasons not to smoke tobacco. 
[02:10.00]Researchers have added another: 
[02:12.80]Smokers have a higher risk of losing their teeth than non-smokers. 
[02:18.88]A new study shows that men who smoke 
[02:21.92]are up to 3.6 times more likely 
[02:25.68]to lose their teeth than men who do not smoke. 
[02:29.44]Women are 2.5 times more likely to lose their teeth than women who don't smoke. 
[02:36.24]The Journal of Dental Research published the findings.  
[02:39.88]Thomas Dietrich was the main writer of the report. 
[02:44.04]He is a professor at the University of Birmingham in England. 
[02:48.76]He says most people lose their teeth from either tooth decay or gum disease, 
[02:54.82]both of which can be caused by smoking. 
[02:58.32]Because smoking can also hide gum disease, 
[03:01.72]smokers may not know about the poor health of their mouths 
[03:05.64]until it is too late and they start losing teeth.
[03:09.58]The study found that it is not only older people who lose their teeth. 
[03:14.78]Researchers discovered that the connection between smoking and tooth loss 
[03:20.17]was stronger among younger people than those who were older.  
[03:25.13]I'm Jim Tedder.
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