科学家们补充说，“没有经过强化训练的马会表现出4到6倍多的‘消极’行为，如咬，踢和‘对实验者大发脾气’。”
The scientists added, "Horses trained without reinforcement expressed four to six times more 'negative' behaviors, such as biting, kicking and 'falling down' on the experimenter."
科学家们补充说，星系的暗物质晕可能会影响到星系自身的演化过程并决定星系的形态——椭圆状或者是涡旋状。
The behavior of a galaxy's dark matter halo could affect its evolution and help determine whether it becomes a spiral or an elliptical, they added.
“马科动物的社会关系是长期持久的，在某些情况下，是终生的。”科学家们补充说，他们的论文已被《动物行为》杂志所收录。
"Equid social relationships are long-lasting and, in some cases, lifelong," added the scientists, whose paper has been accepted for publication in the journal Animal Behavior.
“马科动物的社会关系是长期持久的，在某些情况下，是终生的。”科学家们补充说，他们的论文已被《动物行为》杂志所收录。
"Equid social relationships are long-lasting and, in some cases, lifelong," added the scientists, whose paper has been accepted for publication in the journal Animal Behavior.
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