u QUESTIONS Read the passage. Then listen to the news and fill in the blanks with the information (words, phrases or sentences) you hear. This is Scientific American's 60-second Science, I'm Susanne Bard. More than 140 sign languages are used today, primarily by (1) __________________ around the world. Like spoken languages, each sign language has its own (2) ________________, vocabulary and other special features. For example, American Sign Language and British Sign Language are mutually (3) ___________. In fact, American Sign Language has more in common with French Sign Language, largely because French educators were instrumental in helping get (4) ___________________ established in the United States during the 19th century. But while the lineages and development of spoken languages are well-studied. "There haven't been a lot of large-scale (5) ________________________ of sign languages." University of Texas (at) Austin linguist Justin Power. He and his colleagues aim to address that information gap. "In order to study the question of sign language evolution, we first assembled a database of manual alphabets from dozens of different sign languages around the world. So (6) __________________ is sort of a subsystem within a sign language that is used to represent a written language. So there's (7) ___________________________ that corresponds to each letter." Power's team chose to study manual alphabets because a record of them exists going back to the late 16th century in Europe. To uncover (8) _____________________ between the alphabets, the researchers used the same methods that biologists use to trace relationships between different species, based on their DNA. "The methods grouped sign languages in this study into (9) _______________ main European lineages. And those were Austrian origin, British origin, French origin, Spanish and Swedish." Power says manual alphabets from Austria , France and Spain could be traced back to one-handed manual alphabets from 16th- and 17th-century Spain . But each of these lineages evolved (10) _________________________ of each other. And the British lineage, which uses a two-handed manual alphabet, eventually made it to Australia , New Zealand and India . The study also confirmed the (11) _____________________ origins of American Sign Language and those of other countries, including Mexico , Brazil and the Netherlands . Surprisingly, the Austrian manual alphabet influenced sign languages as far away as (12) _______. But while this lineage has largely died out, remnants of it live on in Icelandic Sign Language today. The study is in the journal Royal Society Open Science. Power says future research comparing the (13) ________________________ of different sign languages could provide even more (14) _________________ about how they've changed over time. "Understanding how sign languages evolve would tell us a lot about the way that (15) __________, in general, evolves." Thanks for listening for Scientific American—60-Second Science. I'm Susanne Bard.