免费日韩片_欧美成人精品一区二区男人小说_国产乱码一区二区三区四区_国产精品国产三级国产aⅴ入口_成人看的污污超级黄网站免费_欧美一级在线免费观看_成人午夜免费无码福利片_国产乱人伦偷精品视频色欲_aaa少妇高潮大片免费看_国产精品1234_亚洲精品国产suv一区88_中文字字幕在线中文无码_精品亚洲区_午夜九九九_国产av国片精品jk制服丝袜_色综合亚洲_亚洲成av人片无码bt种子下载_欧美色就色_精品少妇的一区二区三区四区_男人用嘴添女人下身免费视频

Scientists have cracked the genetic code of a songbird for the first time, identifying more than 800 genes linked to song learning in a finding that may shed light on human speech disorders.

Baby zebra finches learn to sing in virtually the same way as human babies learn to speak -- by copying their elders -- which means the tiny bird should serve as a valuable model for understanding human learning and memory.

"Song learning is an excellent paradigm for all types of learning," said Chris Ponting, a professor with the Medical Research Council Functional Genomics Unit at University of Oxford, who was involved in the research.

"There are experiments that can be done that immediately provide information as to what changes occur in neurons (brain cells) upon the learning of a song. The zebra finch genome provides a tool that allows this exploration," he told Reuters.

The Australian zebra finch, which weighs less than half an ounce (14 grams), is only the second bird to have its genome sequenced, after the chicken in 2004.

Baby finches, like human infants, start off by "babbling" before the young males learn to imitate their father's song and eventually pass it on to the next generation.

As they learn in such a predictable way and many of their genes are also found in humans, finches could provide a window onto the origins of speech disorders, such as autism, strokes, stuttering and Parkinson's disease.

It gives the zebra finch genome a "unique relevance to human neuroscience," a team of international scientists led by Wes Warren of Washington University's Genome Center reported in the journal Nature Wednesday.

Still, untangling the vast web of genetic and molecular factors involved in learning will not be easy.

Experts previously thought there might be around 100 genes involved in zebra finch singing, however, the fact that at least 800 genes exist underlines the sheer complexity of learning.

Significantly, many of the genes activated by bird song do not act like genes in the usual way as code for making proteins. Instead, they belong to the non-coding part of the genome, or what used to be known as "junk DNA."

The analysis of the zebra finch genome adds to growing evidence that these stretches of DNA are not junk, but actually serve a key biological function.

They may have two birds in the bag, but scientists still want to learn more about these feathered descendants of the dinosaurs. Next up is the parrot genome, which researchers hope to complete by the end of this year.