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需要防御外敌时,植物的刺就会增多

来源:慢速英语   时间:2020-05-08 16:56:38

Plant Thorns Increase When Defense Needed

需要防御外敌时,植物的刺就会增多

Plants thrive all over the planet, despite the fact that many animals love to snack on them. Various hypotheses account for all those plants. One is that predators kill enough plant-eating animals to give vegetation a chance. Another is that plants develop physical and chemical means to defend themselves.

尽管有很多动物喜欢吃植物,但是地球上的植物仍然很繁茂。对这些植物有很多假设性的说法。一种说法是:食肉动物吃掉了食草动物,给植物一个生长的机会。另一种说法是:植物自身形成的物理和化学手段来保护它们自己。

Now researchers have teased out some of these factors in an East African savanna.

现在研究者们已经在东非的热带草原找出一些原因。

The impalaan African antelopeeats grasses and trees and is itself eaten by wild dogs and leopards. Impala often munch on a tree called the acacia. Some acacia have thorns, and some don;t.

黑斑羚非洲的一种羚羊吃草和树叶,却野狗和豹子吃掉。黑斑羚经常食用一种金合欢树,有些金合欢树有刺,有些则没有。

The researchers found that the impalaperhaps not surprisinglyprefer thorn-free acacia. Also, the animals avoid woody areas where predators are more likely to hide.

研究者发现黑羚羊也许并不奇怪喜欢无刺的金合欢树。同样,动物尽量避免树木较多的地方,因为那里很有可能隐藏着捕食者。

And as a result, the thorn-free, vulnerable acacia are more plentiful in woody areas with plenty of predators. But the thorny acacia are more numerous on the open savanna, where they need to defend themselves. The study is in the journal Science. [Adam T. Ford et al, Large carnivores make savanna tree communities less thorny]

结果,在林木多的地方,更多的无刺、易受黑羚羊攻击的的金合欢树,在肉食动物较多的树林里生长。但是有刺的金合欢树在热带草原的空旷地区生长的很多,它们也需要保护自己。这一眼就发现在科学期刊上发表。

The researchers say their findings show that both plant defenses and carnivorous predators help plants thrive. They also say that when humans influencein part by eliminating large predatorswe disrupt longstanding, complex systems. And that we should really try to better understand such systems, and our effects on them.

研究者说他们的发现表明:无论植物的防御措施还是食肉动物都促进了植物的繁茂。他们还说人类的影响部分原因是杀死了大型的肉食动物我们打乱了长期存在的复杂的生态体系。我们应该更好地理解这个草原的生态体系,了解我们对草原动植物的影响。

Cynthia Graber

辛西娅格雷伯