Yael: I was walking my cocker spaniel this morning, and we ran into two other dogs---a great dane almost as tall as I am, and a tiny Chihuahua! I can't believe they are all the same species! 今天早上我在遛狗的时候碰到了两只其他的狗——一只是跟我差不多高的大丹犬，还有一只小吉娃娃。简直不能相信他们属于同一物种！Don: You know, scientists are making great strides in understanding the genes that allow such a wide range of shapes, sizes and personalities in different dog breeds. 你知道的，科学家们在探索基因方面已经取得了长足进展，在研究这些不同形状，不同大小，不同性格特点的不同狗的种类的基因。Did you know domestic dogs were bred from wolves about 15,000 years ago? 你知道国内的狗是由一万五千年前的狼繁衍而来的吗？Y: That's pretty recent in evolutionary terms, isn't it? 从进化的角度来讲，那就是近些年的事儿，不是吗？D: Very! Humans have sped up the diversification of dogs by selecting for particular physical or behavioral traits such as size, coat type, trainability, and hunting or herding ability. 太对了。人类通过选择特定的生理和行为特征，如大小、外观、是否可训练性和狩猎型或放牧的能力，已经加快了狗种的多样化。But dogs still show greater variety than any other domesticated animal, and for a long time this variance has largely been unexplained. 但是相比其他家养动物而言，狗显示出更明显的多样性，并且在很长的一段时间内，人们无法解释这种多样性。A group of genetics researchers collaborated with dog breeders and veterinarians to study the DNA from 148 different dog breeds. 一个基因研究小组与狗的饲养者和兽医合作研究了来自148个不同狗品种的DNA。With such a large sample of genes from very different kinds of dogs, they were able to identify regions in the dog DNA that are important in regulating some key traits that differ between breeds. 在来自不同的狗的DNA大样本的研究下，他们鉴定出狗DNA中的区域特征在决定狗的某些区别与其他狗的关键特征方面有着至关重要的作用。Four regions were found that may regulate life span, a breed characteristic that usually decreases with increasing body size. 有四个区域可以调节寿命，而且品种的特性会随着体型的变大而逐渐消失。Regions associated with some behavioral stereotypes like herding, pointing and boldness were also identified. 而且也确认了那些和固有品性相关的区域，像是放牧，勾缝以及大胆尝试。Y: What can they do with this information? 他们会拿这些信息做什么？D: The study could have far-reaching benefits for dogs and their owners. 这项研究对于狗和他们的主人都是有深远影响的。With further research, dog owners and vets could use this information to customize the care, diet and medicines to the particular needs of their breed, and to identify and perhaps prevent breed-specific diseases. 进一步研究会得出，狗主人和兽医可以凭此信息对有特定需求的狗定制保健，饮食和药物，并识别同时也可能会防治特种狗的疾病。
