[This talk contains graphic images] My parents always wanted me to be a doctor. But a doctor that studies how vultures eat dead things is probably not the type of doctor my parents had in mind.
[此演讲包含真实事故图像] 我父母以前总希望我能当医生。 但研究秃鹫怎么吃死尸的医生 可能并不是我父母想要的那种。
(Laughter)
(笑声)
I study vulture scavenging behavior and how vultures affect crime scenes. I'm here to talk to you about how we take vultures for granted in forensic science. Before we do that, I want to tell you a story. So we're going to take a trip, all 1,000 of us. It's May 2014 and we're standing in a park in Nashville, Tennessee, because we've been at a horse race. As we wait for the porta potty, we see two ladies in their Sunday best: heels, pearls and lovely, floppy derby hats. At any moment, we expect them to start talking about their grandma's fine china. But they don't. Instead, we hear them say, "Oh, look. Something must be dead." We look up and to the left and see vultures circling round and round. It occurred to me at this very moment that if these ladies at the derby are aware of vulture's connection to death, then why aren't we talking more about these birds at crime scenes?
我研究秃鹫的清腐行为以及 它们是如何影响犯罪现场的。 今天我就给大家讲一讲 在法医学中,我们对 秃鹫的想当然的看法。 在这之前,我想先给大家讲个故事。 所以我要带大家踏上一段旅程, 在座的1000人一起去。 在2014年5月,我们站在 田纳西州纳什维尔的一个公园里。 因为我们在看赛马。 当我们在等厕所时, 我们看到两位精心装扮的女士, 穿着高跟鞋、戴着珍珠 和可爱的宽大圆礼帽。 我们做好了她们随时会开始谈论 她们祖母的高级瓷器的准备。 但她们没有。 反而,我们听到她们在说, “噢,看啊!” “肯定是有什么东西死掉了。” 我们抬头望去,看到左边 有秃鹫在一圈圈地盘旋。 那个时刻我突然想到, 如果那些戴着圆礼帽的女士, 都明白秃鹫和死亡有联系。 那为何我们不多说一些 在犯罪现场的秃鹫呢?
People know that vultures are connected to death. But they don't really understand how. For example, here's an email I received from a detective in Louisiana: "Lauren, there's been a kidnapping. What buzzards or vultures do we have in Louisiana?" Before we address the kidnapping, I'll first address this buzzard/vulture question I get all the time. Buzzards don't live in the United States. They are hawks that live in Europe. The big black birds you see circling in the sky within the US are vultures. The two types of vultures that live in Louisiana are the turkey vulture and black vulture. To fully understand the role of vultures in forensic science, I'll walk you through this forensic case.
人们知道秃鹫和死亡有联系, 但他们并不知道怎样产生联系的。 举个例子,这是我收到的一封 来自路易斯安纳州一名警探的邮件。 劳伦,这边发生了一起绑架案。 路易斯安纳州有哪些秃鹰或秃鹫呢? 在谈论绑架案前, 我会先回答一下大家经常 问的秃鹰和秃鹫的区别。 秃鹰不生活在美国, 它们是生活在欧洲的一种鹰类。 你在美国看到的那些在 天空盘旋的大黑鸟才是秃鹫。 路易斯安纳州有两种秃鹫: 红头美洲鹫和黑鹫。 为了更好地理解秃鹫 在法医学中的作用, 我会带你看这个法医案件。
From the email, certain things become apparent. We can assume the detective thinks the individual is dead. And he wants to use the birds to try to find the body. Like the ladies in Nashville, the detective thinks that vultures circling in the sky will lead him to the body. It's not that simple. I don't know if you've ever seen a vulture up close or spent much time with them, but they're huge, huge. Six-foot wingspan. Vultures circle in the air because they are too big to flap their wings and fly, so they soar. They soar in thermals, which are vortexes or little tornadoes caused by pressure differences in the air that form throughout the day as the sun heats up the ground. Therefore, when you see a circling vulture, the bird is usually traveling from point A to B, rather than circling above something dead.
从邮件里看出,有些事是确定的。 我们可以假定侦探 认为这个人已经死了, 他希望去用这些鸟儿寻找尸体。 就像纳什维尔的女士们一样, 警探认为天空中盘旋的秃鹫 能够把他带到尸体处, 但事情并没有那么简单。 不知你是否近距离看过秃鹫, 或者花一定的时间观察它们, 它们体型很大,非常大, 展翅有六英尺长。 秃鹫在天空中盘旋, 是因为它们太大,所以 无法拍打翅膀飞翔, 因此,它们在高空翱翔。 它们在热气流中翱翔, 热气流中有涡流或一些小龙卷风, 由白天地面太阳照射造成 空气中的气压不同而产生。 因此,当你看到盘旋的秃鹫时, 那些鸟儿通常是想从A处飞到B处, 而不是围着一堆死掉的东西盘旋。
Actually, if you want to use a vulture to try to find a body, look for a vulture in a tree or on a fence post. Vultures are too big and slow to hunt. So they have to scavenge. In fact, vultures are the only animals in the world that depend upon death as a food source. The turkey vulture that you see here is super cool, because it's one of the few bird species that can actually smell. It hones in on the deceased by sensing a chemical that's coming off the body during decay. The evolutionary role of the vulture is to rid the earth of harmful toxins produced following death. Once death has been detected, the turkey vulture lands and quickly scavenges. Vultures usually remove the eyes first, then tear the skin, start pulling the tissues, and leave you with a skeleton. Therefore, the importance of vultures is not in the air, but on the ground.
实际上,如果想用秃鹫来寻找尸体, 那就寻找树上或围栏柱上的秃鹫。 秃鹫体型太大、行动太慢, 所以很难捕获猎物, 所以它们不得不吃腐肉。 事实上,秃鹫是世界上 唯一以死尸当做食物的动物。 你看这个红头美洲鹫看起来很酷, 因为它是为数不多的 几种嗅觉灵敏的鸟类之一, 它能够迅速分辨出那些 尸体腐烂所散发出来的化学物质。 秃鹫在进化中的角色, 是帮助地球清除尸体 产生的有毒有害的物质。 一旦察觉到死亡, 红头美洲鹫会迅速降落、吃掉尸体。 秃鹫一般会把眼睛去掉, 然后把皮肤撕开, 撕扯肌肉组织,最后只剩骨架。 因此,秃鹫的重要性不在于空中, 而在陆地上。
Vulture scavenging is somewhat gruesome. If you're ever on a bad first date, just reference this talk, and I don't think you'll have to worry about your potential suitor giving you another call.
秃鹰觅食有点可怕, 如果你的第一次约会很糟糕, 就引用这个演讲, 我想你不用担心 你的潜在对象会再打电话给你了。
(Laughter)
(笑声)
Although gruesome, vultures are key forensic players, and here's why. Vultures will consume a dead human just like they will consume roadkill. But you don't ever hear about that, and it's because vultures are so good at what they do. If vultures depend on death for survival and if they scavenge humans, then how can vultures be absent from forensic textbooks and training manuals? The answer: the tradition has been for researchers to exclude animal scavengers from decomposition studies by placing a cage over the decaying subject matter. Why? Because researchers were afraid an animal would run away with their subject matter and they wouldn't have any data to report -- consequently excluding animals' results in a lengthy skeletonization process, and this information is currently what detectives use during investigations.
尽管可怕,但秃鹫可是关键的法医, 原因如下: 秃鹫会吃死人, 就像他们吃路毙的动物一样。 但你从来没听说过这些吧, 是因为秃鹫实在太擅长于此。 如果秃鹫依靠死尸生存, 如果它们吃人类腐肉, 那么为什么法医课本 和训练手册中没提秃鹫呢? 答案是: 在腐解研究中,研究人员往往 将食腐动物排除在外, 而是笼子盖住腐解的物体。 为什么? 因为研究者担心动物 会带着目标物跑掉, 这样就没有数据可汇报—— 最终,就把动物作用的结果 排除在了冗长解剖过程之外, 目前侦探在调查中 使用的正是这样的信息。
A lot of times at a crime scene when people see a skeletonized body, they think, "Wow, this has been here for a really long time undiscovered." Oh, no, no, no, no. Vultures accelerate decay. And the skeletonized body could have been there for as little as five days if scavenged by vultures. The failure to account for vulture scavenging can result in forensic scientists inaccurately estimating how long someone has been dead and then searching through the wrong missing person's files. Therefore, the goal is to get forensic scientists to focus on vulture evidence and to get law enforcement to consider vulture scavenging and a possible recent death when skeletal remains are found.
很多时候在犯罪现场, 当人们看到仅剩的骨架时, 他们心想:”喔,这是过了 很长时间才被发现的“, 哦,不,不,不,不, 是秃鹫加速了分解的过程。 骨架可能在那里只有不足5天, 如果是被秃鹫清理过的话。 如果没计算秃鹫分解的因素, 可能会导致法医无法准确估算 一个人到底死了多久, 然后,导致搜索错误的失踪人员档案。 所以,我们的目的是, 让法医学专家关注秃鹫的证据, 并让执法人员考虑秃鹫食腐情况, 在发现骨骸时,就能推算出 可能的近期死亡时间。
Let's get back to the importance of the kidnapping case. I responded to the detectives and told them that vultures like areas with water. They like areas with white-tailed deer, they typically arrive within the first five days following death, they're going to leave an intact spinal column and feathers. The detectives write back and say, "We found the body buried in a shallow grave. We also found the feathers you mentioned." But there appeared to be a problem because the feathers were located 40 yards from where the body was found. The feathers were next to a bloody pine cone. Vultures aren't attracted to blood, and they typically don't wander. They might wander 40 feet, but they're not going to wander 40 yards. That would be a waste of energy for a bird that doesn't know when it will get its next meal. So my first job here was to determine if vultures were at the scene. Indeed, the feather by the pine cone was consistent with the turkey vulture. So why in the world would a vulture wander 40 yards?
让我们回到绑架案的重要性, 我给侦探答复, 并告知他们秃鹫喜欢有水的地方。 它们喜欢有白尾鹿的地方, 通常在死亡后的头五天内到达, 会留下完整的脊柱和羽毛。 侦探回信说: “我们发现尸体被埋在一个浅坟里, 我们也发现了你提到的羽毛。“ 但那显然有个问题, 因为羽毛位于发现尸体的40码外, 羽毛就在一个血迹斑斑的松果旁边。 秃鹫不会被血液所吸引, 它们通常不会游荡。 它们可能会走上40英尺, 但不会溜达到40码外。 对秃鹫而言,那纯粹是浪费能量, 当它不知道下一顿美餐在哪里时。 所以我首先要确认秃鹫是否在现场。 确实,松果旁边的羽毛 是红头美洲鹫的。 那为什么秃鹫会浪荡个40码远呢?
One of the reasons I love vultures is because they tend to operate in a manner that can be explained by biology and physics. I started mentally going through the numerous bating experiments I had conducted at a body farm in Texas. A body farm is a place where you can donate your body to science. I also went through my experiences with trapping and GPS tagging vultures. And then the year-long process of monitoring vultures via remote GPS technology. Next, I brought up my field notes and had an "Aha!" moment. I knew of two things that would lure a vulture 40 yards from a body. Guts and brain matter. I presented this information to the detectives and learned that they suspected the victim had been incapacitated by blunt force trauma to the head. The blow to the head was thought to have occurred in the area where the pine cone was found, and then the victim was drug 40 yards and buried in a shallow grave. This suggested that brain matter was the lure for the vulture and illustrates how studying vulture behavior can help piece together some of the evidence.
我喜欢秃鹫的一个原因, 是由于它们的行为 在生物学和物理学上可解释。 我开始在脑海中回想 我曾在德州尸体场里 做过的大量抑制实验, 尸体场是人们把遗体 捐献给科研的地方。 我也回想了自己捕捉 和用GPS标记秃鹫的经历, 和之后长达一年的 通过远程GPS技术监视秃鹫的过程。 接着,我拿出现场笔记一看, 然后恍然大悟。 我知道在尸体40码外 有两件事情会诱惑到秃鹫, 就是内脏和大脑物质。 我把这个信息告诉了侦探们, 得知他们怀疑受 害者头部受钝力外伤, 并因此丧失了行动能力。 他们认为对头部的重击 就发生在发现松果的地方, 然后受害者被拖到40码外、 埋在浅坟里。 这解释了大脑物质 是诱惑秃鹫的原因, 并展示了对秃鹫行为的研究 是如何帮助把证据拼凑在一起。
The detectives also sent me this photo. The victim's arm is sticking up out of the grave. As a forensic scientist, you have to think about the whole picture. The feather by the pine cone indicated that vultures were at the scene. This crime scene photo also depicts characteristic vulture scavenging behavior. We zoom in, we see a white down feather, which is characteristic of the turkey vulture. Also note that the skin has a cut-like tear near the wrist. The turkey vulture smells the decay, lands. It can get through the pine needles, pull out the hand, it's going to tear the skin with its beak and then start pulling the soft tissues away from the bone. Just tear and pull, tear and pull, tear and pull.
侦探也向我传来这照片。 受害者的手臂从坟墓里伸出来。 作为法医科学家,你需要考虑整幅画面。 松果旁的羽毛意味着秃鹫在现场, 这张犯罪现场照片同样描述了 秃鹰清除行为的特征。 放大后可发现一根白色羽毛, 这是红头美洲鹫的特征, 请注意手腕处皮肤 有类似刀切的撕裂痕迹。 红头美洲鹫嗅到了腐物,然后降落。 它可以穿过松针, 拉出手, 用它的喙撕裂皮肤, 然后开始把软组织从骨头上拉下来。 就这样扯拉,扯拉,扯拉。
This photo illustrates the scavenging efficiency of vultures. This is important because it helps support the time line the detectives are putting together for the murder. There's not a whole lot of evidence. You're not likely going to see the vultures at the crime scene. Instead, vultures just leave these very subtle clues. Rather than looking for the vulture, look for the feathers and pristine bones. Vultures are important because they are so good and fast at what they do. They're like tornadoes. If you blink, you will miss them.
这个照片展现了秃鹫的清除效率。 这一点很重要, 因为可帮助侦探们 拼凑凶杀案的时间线。 这并没有太多的证据。 你不太可能在犯罪现场看到秃鹫; 相反,秃鹫只会留下这些 非常微妙的线索。 与其寻找秃鹫, 不如寻找羽毛和新的骨头。 秃鹫非常重要, 因为它们对于此道既擅长又快, 它们就像龙卷风一样, 一眨眼,就会错过它们。
I provided my opinion about the vulture evidence to the detective. And he presented the vulture evidence in court. The kidnapping case was a death penalty case. And the defendant was found guilty. This case illustrates how studying vulture behavior helps innovate forensic science. Someone who has been murdered deserves the most thorough investigation possible. When we include vultures in forensic studies, we paint a more thorough picture of what happened, when it happened and who it happened to. So, the next time you're at a crime scene with a dead body --
我把有关秃鹫证据的观点 提供给侦探, 他在法庭上展示了秃鹫的证据。 这桩绑架案是一起死刑案, 被告被判有罪。 这个案件展示了研究秃鹫行为 如何帮助法医科学研究。 被谋杀的人 值得最彻底地进行调查。 当我们把秃鹫包含在法医研究中, 我们就描绘了一幅 发生了什么、何时发生、 发生在谁身上的更全面的画面。 所以,下次你在犯罪现场看到尸体——
(Laughter)
(笑声)
look to the ground to find the clues vultures have left. And if anyone ever brings up vultures on a date, you'll know they're a keeper.
找找地上有没有秃鹫留下的线索。 如果有人在约会时带着秃鹫, 你会知道他们是最佳对象哦。
Thank you.
谢谢大家。
(Applause)
(鼓掌)