[原创翻译]倾听侏罗纪蝈蝈的呼唤

原文地址：http://cosmiclog.msnbc.msn.com/_ ... -a-jurassic-katydid

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2012-2-9 12:04 上传

侏罗纪蝈蝈“悦耳古鸣螽”（Archabolilus musicus）复原图

Hear the call of a Jurassic katydid

倾听侏罗纪蝈蝈的呼唤

By Alan Boyle

Researchers have re-created the love song of a katydid from 165 million years ago, based on an analysis of fossilized wings found in northwest China. They say the chirp adds an aural dimension to our picture of the forests of the Jurassic Era.

基于对中国西北部地区发现的翅膀化石的分析，研究人员已经重新创造了1.65亿年前蝈蝈的情歌。他们说，这种虫鸣声，从听觉层面上，为我们了解的侏罗纪时代森林景观增添了新的内容。

"The Jurassic forest was already packed with many animals singing at night," Fernando Montealegre-Zapata, a University of Bristol biologist who specializes in insect sounds, told me today. "I'm not just talking about the crickets but the frogs. That would create a noisy environment, and in a noisy environment the best way to communicate is with a single frequency, and loudly."

“侏罗纪森林的夜晚，已经充满了很多动物的歌声。”专门研究昆虫声音的布里斯托尔大学生物学家费尔南多·蒙特亚莱格雷-萨帕塔今天告诉我。“我不仅在谈论蟋蟀，还有青蛙。这将创造一种嘈杂的环境，在嘈杂的环境中，最好的沟通方式是单一的频率，放大声音。”

That assumption fits with the analysis conducted by Montealegre-Zapata and his colleagues, which appears in this week's Proceedings of the National Academy of Sciences. They started with a well-preserved Middle Jurassic fossil, one of several found by Chinese paleontologists at Inner Mongolia's Jiulongshan Formation. This particular fossil revealed the wing structure for a long-extinct species of katydid, also known as a bushcricket, which has been dubbed Archabolilus musicus.

这种假设符合蒙特亚莱格雷及其同事们做出的分析，它出现在本周的《国家科学院记录汇编》中。他们的研究开始于一块保存完好的中侏罗世化石，该化石是中国古生物学家在内蒙古自治区九龙山组发现的多块化石之一。这块特殊的化石，揭示了一种早已灭绝的蝈蝈的翅膀结构，这种蝈蝈类似灌丛蟋蟀，正式名称是悦耳古鸣螽。

In life, the bug would have had relatively large wings, measuring more than 2.8 inches (7 centimeters) in length, with broad stripes of color. Its closest living relatives include katydids (Tettigonidae) and grigs (Prophalangopsidae).

在生活中，这种昆虫应该拥有相对较大的翅膀，测量长度超过2.8英寸（7厘米），具有宽阔的彩色条纹。目前存活的最接近它的动物包括现代螽斯和鸣螽。

The researchers made detailed measurements of the fossil wing's parts, including the organs that katydids use to produce their mating calls. Scientists believe that ancient katydid, like their modern-day descendants, strummed their songs by rubbing the tiny teeth of one wing against a plectrum on the other wing.

研究人员详细测量了翅膀化石的各部分，包括蝈蝈用来产生交配呼唤声音的组织。科学家们相信，这种古老的蝈蝈，就像它们的现代后裔一样，通过把一片翅膀上的细小牙齿与另一片翅膀上的拨片相互摩擦，来弹奏出歌声。

For comparison's sake, Montealegre-Zapata and a colleague of his at the University of Bristol, Daniel Robert, analyzed the wing structures of 59 modern-day katydid species. They fed all those readings and the characteristics of the insects' songs into a mathematical model. Then they looked at where A. musicus would fit in that model.

为了便于比较，蒙特亚莱格雷和他在布里斯托尔大学的同事丹尼尔·罗伯特，分析了59种现代蝈蝈的翅膀结构。他们把所有这些读数和昆虫歌声的特征全部输入了一个数学模型。随后，他们寻找了悦耳古鸣螽在模型中的合适位置。

Their conclusion, based on the size of the wing and the precise spacing of the teeth, was that the Jurassic katydid would emit a steady tone at a frequency of 6.4 kHz for 16 milliseconds. That was enough information to reconstruct the sound, which you can hear by clicking on the video button above.

基于翅膀大小和翅膀上牙齿的精确间距，他们的结论是，这种侏罗纪蝈蝈可以在16毫秒内，以6.4千赫的频率，发出稳定的声调。这些信息足够重建它的声音，您可以点击上方的视频按钮来听到。

The researchers' reconstruction has the calls coming less than a second apart, because that would be the typical frequency for species of katydids that are not threatened by bats. Paleontologists say bats were not a threat to Jurassic bugs because they didn't exist during that period.

根据研究人员重建的声音，它们发出呼唤的间隔不足一秒，因为这对于没有受到蝙蝠威胁的蝈蝈来说，是一种典型的频率。古生物学家说，蝙蝠不会威胁到侏罗纪的昆虫，因为它们在那个时期并不存在。

The single-tone call would have come through loud and clear to other katydids, Montealegre-Zapata said in a news release.

蒙特亚莱格雷在一份新闻稿中说，这种单一声调的呼唤，将通过响亮而清晰的特点传递给其它的蝈蝈。

"For Archaboilus, as for living bushcricket species, singing constitutes a key component of mate attraction," he said. "Singing loud and clear advertises the presence, location and quality of the singer, a message that females choose to respond to — or not. Using a single tone, the male's call carries further and better, and therefore is likely to serenade more females. However, it also makes the male more conspicuous to predators if they have also evolved ears to eavesdrop on these mating calls."

“对于悦耳古鸣螽，以及现存的灌丛蟋蟀，歌唱构成了异性吸引力的重要组成部分。”他说。“响亮而清晰的歌声，展示了歌手的存在、位置和素质，雌虫根据这些信息来选择回应 -- 或不回应。使用单一的声调，雄虫的呼唤可以传播得更远、更好，因此可能招来更多的雌虫。然而，这也使雄虫更容易引起捕食者的注意，如果捕食者同样进化出了耳朵，可以偷听这些异性的召唤。”

His guess is that the Jurassic katydid was a nocturnal creature, since all present-day katydids that use musical calls are nocturnal. That would have kept the crickets from being picked off by daytime predators such as the feathered, flying Archaeopteryx. But Montealegre-Zapata said they may have made tasty morsels for bug-eating Jurassic mammals such as Morganucodon and Dryolestes (which could conceivably hear the cricket calls).

他猜测，侏罗纪蝈蝈是一种夜间活动的动物，因为现在所有使用音乐召唤的蝈蝈都是夜间活动的。这应该会使它避免被白天活动的捕食者抓走，如长着羽毛、会飞行的始祖鸟。但是蒙特亚莱格雷说，对于捕食昆虫的侏罗纪哺乳动物，如摩根尖齿兽和鼩兽（据信它们都可以听到蝈蝈的叫声），这种蝈蝈可能就是小点心。

The findings strongly suggest that katydids were well-adapted for music-making during the Middle Jurassic, 165 million years ago. That led the researchers to speculate that the katydid's distant ancestors might have begun chirping more than 50 million years earlier, during the Triassic Period, thanks to "the formation of random teeth across several veins on the forewings, and the associated production of noisy sounds."

这些研究结果强烈地表明，蝈蝈在1.65亿年前的中侏罗世期间，就已经非常适合产生音乐。这使研究人员推测，这种蝈蝈的远祖，可能早在此前5000多万年的三叠纪时期，就已经开始鸣叫。这要归功于“在前翅上，穿过几条纹路随机分布的牙齿的形成，以及相关噪音的产生。”

Reconstructing the ancient song of a katydid could also help answer questions about modern-day insect communications, Montealegre-Zapata said. There's quite a bit of variation to the chirps of katydids and crickets, as you'll find out if you listen to the audio clips on this webpage. Over time, musical bugs may well change their tune to suit their biggest fans and frustrate their worst foes.

蒙特亚莱格雷说，重建这种古老蝈蝈的歌声，同样有助于解答关于现代昆虫交流的问题。如果您收听了这个网页上的音频剪辑，您就会发现，蝈蝈和蟋蟀的鸣叫声，有相当多的变化。随着时间的推移，演奏音乐的昆虫很可能改变自己的声调，以取悦于它们主要的追求者，并逃避它们最大的敌人。

Montealegre-Zapata said the reconstruction of the Jurassic katydid's love song "suggests the evolutionary mechanisms that drove modern bushcrickets to develop ultrasonic signals for sexual pairing and for avoiding an increasingly relevant echolocating predator — but that only happened 100 million years later, possibly with the appearance of bats."

蒙特亚莱格雷说，重建侏罗纪蝈蝈的情歌“表明，进化机制驱使当代灌丛蟋蟀发展出了超声波信号，用于异性交配，以及逃避日益依赖回声定位的捕食者 -- 但是这种情况只发生在1亿年以后，很可能是由于蝙蝠的出现。”

In addition to Montealegre-Zapata and Robert, authors of the PNAS study, "Wing Stridulation in a Jurassic Katydid (Insect, Orthoptera) Produced Low-Pitched Musical Calls to Attract Females," include Jun-Jie Gu, Michael S. Engel, Ge-Xia Qiao and Dong Ren.

这篇国家科学院科研论文《侏罗纪螽斯（直翅目昆虫）翅的摩擦发出低频鸣声吸引雌性昆虫》的作者，除了蒙特亚莱格雷-萨帕塔和罗伯特，还包括顾俊杰（首都师范大学博士生）、迈克尔·恩格尔、乔格侠（中科院动物研究所研究员）和任东（首都师范大学教授）。


原文地址：http://cosmiclog.msnbc.msn.com/_ ... -a-jurassic-katydid

Jurassic_katydid .jpg (11.64 KB, 下载次数: 12)

下载附件 保存到相册

2012-2-9 12:04 上传

侏罗纪蝈蝈“悦耳古鸣螽”（Archabolilus musicus）复原图

Hear the call of a Jurassic katydid

倾听侏罗纪蝈蝈的呼唤

By Alan Boyle

Researchers have re-created the love song of a katydid from 165 million years ago, based on an analysis of fossilized wings found in northwest China. They say the chirp adds an aural dimension to our picture of the forests of the Jurassic Era.

基于对中国西北部地区发现的翅膀化石的分析，研究人员已经重新创造了1.65亿年前蝈蝈的情歌。他们说，这种虫鸣声，从听觉层面上，为我们了解的侏罗纪时代森林景观增添了新的内容。

"The Jurassic forest was already packed with many animals singing at night," Fernando Montealegre-Zapata, a University of Bristol biologist who specializes in insect sounds, told me today. "I'm not just talking about the crickets but the frogs. That would create a noisy environment, and in a noisy environment the best way to communicate is with a single frequency, and loudly."

“侏罗纪森林的夜晚，已经充满了很多动物的歌声。”专门研究昆虫声音的布里斯托尔大学生物学家费尔南多·蒙特亚莱格雷-萨帕塔今天告诉我。“我不仅在谈论蟋蟀，还有青蛙。这将创造一种嘈杂的环境，在嘈杂的环境中，最好的沟通方式是单一的频率，放大声音。”

That assumption fits with the analysis conducted by Montealegre-Zapata and his colleagues, which appears in this week's Proceedings of the National Academy of Sciences. They started with a well-preserved Middle Jurassic fossil, one of several found by Chinese paleontologists at Inner Mongolia's Jiulongshan Formation. This particular fossil revealed the wing structure for a long-extinct species of katydid, also known as a bushcricket, which has been dubbed Archabolilus musicus.

这种假设符合蒙特亚莱格雷及其同事们做出的分析，它出现在本周的《国家科学院记录汇编》中。他们的研究开始于一块保存完好的中侏罗世化石，该化石是中国古生物学家在内蒙古自治区九龙山组发现的多块化石之一。这块特殊的化石，揭示了一种早已灭绝的蝈蝈的翅膀结构，这种蝈蝈类似灌丛蟋蟀，正式名称是悦耳古鸣螽。

In life, the bug would have had relatively large wings, measuring more than 2.8 inches (7 centimeters) in length, with broad stripes of color. Its closest living relatives include katydids (Tettigonidae) and grigs (Prophalangopsidae).

在生活中，这种昆虫应该拥有相对较大的翅膀，测量长度超过2.8英寸（7厘米），具有宽阔的彩色条纹。目前存活的最接近它的动物包括现代螽斯和鸣螽。

The researchers made detailed measurements of the fossil wing's parts, including the organs that katydids use to produce their mating calls. Scientists believe that ancient katydid, like their modern-day descendants, strummed their songs by rubbing the tiny teeth of one wing against a plectrum on the other wing.

研究人员详细测量了翅膀化石的各部分，包括蝈蝈用来产生交配呼唤声音的组织。科学家们相信，这种古老的蝈蝈，就像它们的现代后裔一样，通过把一片翅膀上的细小牙齿与另一片翅膀上的拨片相互摩擦，来弹奏出歌声。

For comparison's sake, Montealegre-Zapata and a colleague of his at the University of Bristol, Daniel Robert, analyzed the wing structures of 59 modern-day katydid species. They fed all those readings and the characteristics of the insects' songs into a mathematical model. Then they looked at where A. musicus would fit in that model.

为了便于比较，蒙特亚莱格雷和他在布里斯托尔大学的同事丹尼尔·罗伯特，分析了59种现代蝈蝈的翅膀结构。他们把所有这些读数和昆虫歌声的特征全部输入了一个数学模型。随后，他们寻找了悦耳古鸣螽在模型中的合适位置。

Their conclusion, based on the size of the wing and the precise spacing of the teeth, was that the Jurassic katydid would emit a steady tone at a frequency of 6.4 kHz for 16 milliseconds. That was enough information to reconstruct the sound, which you can hear by clicking on the video button above.

基于翅膀大小和翅膀上牙齿的精确间距，他们的结论是，这种侏罗纪蝈蝈可以在16毫秒内，以6.4千赫的频率，发出稳定的声调。这些信息足够重建它的声音，您可以点击上方的视频按钮来听到。

The researchers' reconstruction has the calls coming less than a second apart, because that would be the typical frequency for species of katydids that are not threatened by bats. Paleontologists say bats were not a threat to Jurassic bugs because they didn't exist during that period.

根据研究人员重建的声音，它们发出呼唤的间隔不足一秒，因为这对于没有受到蝙蝠威胁的蝈蝈来说，是一种典型的频率。古生物学家说，蝙蝠不会威胁到侏罗纪的昆虫，因为它们在那个时期并不存在。

The single-tone call would have come through loud and clear to other katydids, Montealegre-Zapata said in a news release.

蒙特亚莱格雷在一份新闻稿中说，这种单一声调的呼唤，将通过响亮而清晰的特点传递给其它的蝈蝈。

"For Archaboilus, as for living bushcricket species, singing constitutes a key component of mate attraction," he said. "Singing loud and clear advertises the presence, location and quality of the singer, a message that females choose to respond to — or not. Using a single tone, the male's call carries further and better, and therefore is likely to serenade more females. However, it also makes the male more conspicuous to predators if they have also evolved ears to eavesdrop on these mating calls."

“对于悦耳古鸣螽，以及现存的灌丛蟋蟀，歌唱构成了异性吸引力的重要组成部分。”他说。“响亮而清晰的歌声，展示了歌手的存在、位置和素质，雌虫根据这些信息来选择回应 -- 或不回应。使用单一的声调，雄虫的呼唤可以传播得更远、更好，因此可能招来更多的雌虫。然而，这也使雄虫更容易引起捕食者的注意，如果捕食者同样进化出了耳朵，可以偷听这些异性的召唤。”

His guess is that the Jurassic katydid was a nocturnal creature, since all present-day katydids that use musical calls are nocturnal. That would have kept the crickets from being picked off by daytime predators such as the feathered, flying Archaeopteryx. But Montealegre-Zapata said they may have made tasty morsels for bug-eating Jurassic mammals such as Morganucodon and Dryolestes (which could conceivably hear the cricket calls).

他猜测，侏罗纪蝈蝈是一种夜间活动的动物，因为现在所有使用音乐召唤的蝈蝈都是夜间活动的。这应该会使它避免被白天活动的捕食者抓走，如长着羽毛、会飞行的始祖鸟。但是蒙特亚莱格雷说，对于捕食昆虫的侏罗纪哺乳动物，如摩根尖齿兽和鼩兽（据信它们都可以听到蝈蝈的叫声），这种蝈蝈可能就是小点心。

The findings strongly suggest that katydids were well-adapted for music-making during the Middle Jurassic, 165 million years ago. That led the researchers to speculate that the katydid's distant ancestors might have begun chirping more than 50 million years earlier, during the Triassic Period, thanks to "the formation of random teeth across several veins on the forewings, and the associated production of noisy sounds."

这些研究结果强烈地表明，蝈蝈在1.65亿年前的中侏罗世期间，就已经非常适合产生音乐。这使研究人员推测，这种蝈蝈的远祖，可能早在此前5000多万年的三叠纪时期，就已经开始鸣叫。这要归功于“在前翅上，穿过几条纹路随机分布的牙齿的形成，以及相关噪音的产生。”

Reconstructing the ancient song of a katydid could also help answer questions about modern-day insect communications, Montealegre-Zapata said. There's quite a bit of variation to the chirps of katydids and crickets, as you'll find out if you listen to the audio clips on this webpage. Over time, musical bugs may well change their tune to suit their biggest fans and frustrate their worst foes.

蒙特亚莱格雷说，重建这种古老蝈蝈的歌声，同样有助于解答关于现代昆虫交流的问题。如果您收听了这个网页上的音频剪辑，您就会发现，蝈蝈和蟋蟀的鸣叫声，有相当多的变化。随着时间的推移，演奏音乐的昆虫很可能改变自己的声调，以取悦于它们主要的追求者，并逃避它们最大的敌人。

Montealegre-Zapata said the reconstruction of the Jurassic katydid's love song "suggests the evolutionary mechanisms that drove modern bushcrickets to develop ultrasonic signals for sexual pairing and for avoiding an increasingly relevant echolocating predator — but that only happened 100 million years later, possibly with the appearance of bats."

蒙特亚莱格雷说，重建侏罗纪蝈蝈的情歌“表明，进化机制驱使当代灌丛蟋蟀发展出了超声波信号，用于异性交配，以及逃避日益依赖回声定位的捕食者 -- 但是这种情况只发生在1亿年以后，很可能是由于蝙蝠的出现。”

In addition to Montealegre-Zapata and Robert, authors of the PNAS study, "Wing Stridulation in a Jurassic Katydid (Insect, Orthoptera) Produced Low-Pitched Musical Calls to Attract Females," include Jun-Jie Gu, Michael S. Engel, Ge-Xia Qiao and Dong Ren.

这篇国家科学院科研论文《侏罗纪螽斯（直翅目昆虫）翅的摩擦发出低频鸣声吸引雌性昆虫》的作者，除了蒙特亚莱格雷-萨帕塔和罗伯特，还包括顾俊杰（首都师范大学博士生）、迈克尔·恩格尔、乔格侠（中科院动物研究所研究员）和任东（首都师范大学教授）。