男子养了只「双头小青龟」，两个头还会争抢食物，双头动物在生物学上是怎么形成的？到底哪个脑袋在做主？ (opens in new tab)

<div class="main-wrap content-wrap"> <div class="headline"> <div class="img-place-holder"></div> </div> <div class="content-inner"> <div class="question"> <h2 class="question-title"></h2> <div class="answer"> <div class="meta"> <img class="avatar" src=" referrerpolicy="no-referrer"> <span class="author">瞻云，</span><span class="bio">先让一部分知识有趣起来</span> <a href=" class="originUrl" hidden="">查看知乎原文</a> </div> <div class="content"> <p><strong>人都有两头的，更不用说乌龟了。</strong></p> <p>现今还在世的，最著名“双...