Several vertebrate species can distinguish between, say, two and five bananas —______（填一句话，本句开头不大写。）________
Now, new research suggests that pigeons, like primates, can follow these abstract numerical rules. The study is in the journal Science.
Researchers trained pigeons with cards on which were pictures of one, two or three shapes, sometimes in different sizes and colors. The birds were ultimately able to correctly pick a card with one large green square first, followed by a card with two small red ovals, followed by one showing three long blue rods.
Then, the pigeons demonstrated a new ability — faced with two cards each showing up to nine images, they could tell which card had more. Which indicates that they had an abstract understanding of the single-digit amounts. Rhesus monkeys trained in a similar way displayed the same talents. Whether this shared ability evolved independently or came from a common ancestor is unclear. But it is clear that birdbrains aren’t so dumb.
but with the exception of primates, they can't grasp the numerical rules that would let them arrange the piles of fruit from least to most.
with the exception of adv. 除…以外 numerical adj. 数字的, 用数字表示的, 数值的 一些脊椎物种有能力把2根香蕉和5根香蕉区分开。但是除灵长类动物之外，它们无法掌握把水果从少放到多的数字规则。现在，新的研究表明像灵长类动物一样，鸽子能掌握这些抽象的数字规则。这项研究发表于期刊“科学”上。 研究人员用一些印有数字的卡片来训练这些鸽子，卡片上是表示1、2、3含义的形状，有时这些形状的大小、颜色会有些不同。这些鸽子最终能够正确地进行排序。首先，它们选出一张印有一个绿色大方块的卡片。然后，选出一张有两个红色小椭圆的卡片。最后，选出有三个蓝色长棒的卡片。 然后，鸽子们还展示出了新的技能，当面对每张都有多达九种图形的两张卡片时，它们能区分出哪种卡片上的数字加起来之后更大。这一技能表明，它们能理解个位数的抽象含义。用同样方法训练的猕猴也能习得相同的技能。目前尚无定论这一相同的能力是两个物种独立进化的结果还是起源于同一祖先。但有一点是肯定的，那就是“傻”鸟不傻。