The knee cap is one example of a sesamoid .

膝盖骨是种子骨的一个例子。

This " thumb " is really just a sesamoid , a bit of bone that typically forms inside tendons and ligaments where they cross joints .

这个“拇指”其实只是一个种子骨，通常是在跨关节的肌腱和韧带内形成的一小块骨头。

But in the panda , the sesamoid on the outside base of the true thumb became enlarged , taking on a digit-like identity that helps the animal eat more efficiently .

但对于熊猫，位于真正的拇指外的种子骨增大了，以一个类似指头的身份，帮助这个动物吃起来效率更高。