科学美国人60秒 SSS 哪一个先长出来:长鼻还是花?v(在线收听) |
Which Came First: The Proboscis or the Flower? To learn about the plant life of long ago, scientists dig through layers of the Earth, looking for fossil clues. Like bits of fossilized pollen, or spores."And that's where I come in." Timo van Eldijk (EL-dike) is an evolutionary biologist at Utrecht University. He was called into action when his pollen-hunting pals noticed something altogether different, in a sample of sediment more than 200 million years old [ok?] dug from a thousand feet below the surface of Germany: bits of insect. 为了研究很久以前的植物,科学家们挖掘了地球的各个层面,寻找植物化石,像化石花粉或孢子碎片等,“这就是我进来的地方。” Timo van Eldijk(EL-dike)是乌得勒支大学的进化生物学家。当他的朋友注意到一些完全不同的沉积物时,他被邀请来,在从德国表面下1000英尺的地方,挖掘出来200多万年的沉积物样本中,其中有一小部分是昆虫化石样本。 "I took a human nose hair, because that's the way you isolate these things. You have a needle tipped with a human nose hair, apparently it has just the right springiness for the isolation."Whose nose hair? "I don't actually know. There was a joke going around it was one of the professors, but we don't actually know." “我拿了一个人的鼻毛,因为这是你隔离这些东西的方法,你的针头上有一个人的鼻毛,显然它有适合隔离的弹性。那么这是谁的鼻毛呢? “实际上,我并不知道,周围有一个笑话流传,称这是其中一位教授的,但我们并不知道。 So, using someone's nose hair, van Eldijk picked through the sludgy sediment, and isolated the tiny scales of moth wings—the stuff that looks like dust, if you touch a butterfly or moth.His team scanned those scales with an electron microscope, and made a crucial discovery: some of the scales were hollow. The fossil record shows that: "First came the proboscis and then came the hollow scales. We can then infer, if we find the hollow scales, there must already have been a proboscis." 所以,用一个人的鼻毛,van Eldijk从泥泞沉积物中拣出来,隔开了小小的蛾翅膀——那些看起来像灰尘的东西。他的团队用电子显微镜扫描了这些鳞片,注意到一个重要发现:有些尺度是空的。化石记录显示:“先是长鼻,然后是空心鳞片,我们可以推断,如果发现空心鳞片,就表明已经有长鼻了。” So what’s the big deal? The finding means that these samples predate existing evidence for the first butterfly tongues by 70 million years. Which in turn implies that an early version of the proboscis, which in modern insects can pry into a flower's nooks and crannies for nectar, appears to have evolved before the appearance of flowers—not as a response. The study is in the journal Science Advances. 那么有什么大不了的呢?这一发现意味着,这些样本早于七千万年前就有了。第一批蝴蝶舌头的现有证据。这反过来暗示了一种早期的长鼻。在现代昆虫中,可以撬开花的角落和花蜜,在花出现之前,似乎已经进化了,而不是作为回应。这项研究结果发表在“科学进展”期刊上。 The early proboscis might have been used to pluck drops of liquid from the tips of ancient forms of today’s pine tree cones. And it’s clear that these sucking tongues underwent a lot of remodeling after the emergence of flowers, as flowers and moths co-evolved. 早期长鼻可能已经被用来从古代松树锥体尖端采摘液体。很明显,这些吸舌在花朵出现后,经历了大量的重塑,如花和飞蛾的共同演变。 But van Eldijk is hoping insect scales might become more widely used as a tool to investigate the ancient world. "We're hoping that people will start recognizing them in other places. You can even imagine a scenario in which we can reconstruct past ecosystems based on the scales you find in a core, similar to the way we do with pollen now."All scientists have to do is follow their noses—or at least their nose hairs. 但van Eldijk希望,昆虫可能会被广泛用作调查古代世界的工具。“我们希望,人们能够在其他地方开始认识他们,甚至可以想象一个情景,我们可以根据你在核心中发现的尺度,重建过去的生态系统,类似于我们现在用花粉的方式。”所有科学家必须要做的是,跟随他们的鼻子——至少是他们的鼻毛来发现新东西。 |
原文地址:http://www.tingroom.com/lesson/sasss/2018/1/422946.html |