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Titanosaurs—those long-necked, herbivorous sauropods that walked on four legs—are one of the most iconic groups of dinosaurs.
泰坦巨龙—那些脖子长长的、四只脚行走的食草蜥脚类动物—是恐龙界中最具标志性的种类之一。
I mean, when you think dinosaur, it's pretty much either them or T. rex.
我是说，当大家想起恐龙时，脑海中浮现的要么是它们要么就是霸王龙。
And they don't just dominate dino pop culture, they were pretty dominant in their time, too.
它们不仅主宰着恐龙流行文化，也统治着自己所在的时代。
They're thought to be the biggest animals to have ever walked on land, and by the end of the Cretaceous, they were all over the place.
它们被认为是行走在陆地上的最大的动物，在白垩纪末期，它们遍及各地。
We've found their fossils on every continent except for Antarctica. But their early years are still kind of a mystery.
我们在除了南极洲之外的每个大陆都发现了它们的化石。但是它们的早起时代仍是个谜。
And that's why paleontologists are excited about a new fossil described this week in the journal PLoS ONE.
因此古生物学者对本周《PLoS ONE》期刊中描述的新化石非常激动。
Not only is the titanosaur over 100 million years old, they found a lot of bones from the same animal,
不仅仅是因为泰坦巨龙已有亿年之久，他们发现了同种动物身上的很多骨头，
and it's already providing intriguing insights into titanosaur evolution.
并且新化石提供了洞察泰坦巨龙进化的迷人视角。
We have plenty of fossil evidence that tells us titanosaurs reached peak diversity in the late Cretaceous era between 100 and 66 million years ago,
我们有很多化石证据表明泰坦巨龙在100到66百万年前的白垩纪后期达到了多样化的巅峰，
but we don't know all that much about how they got started.
但是我们对它们的起源知之甚少。
The vast majority of what we do know comes from South America.
我们掌握的大部分信息都源于南美洲。
And scientists have also found a handful of titanosaurs in Africa,
并且科学家们已经在非洲发现少量泰坦巨龙，
which suggests the lineage started when the two continents were part of one supercontinent.
这表明当两块大陆还属于一块超大陆时，这个物种就开始了。
But it was thought that the creatures in what's now sub-Saharan Africa were kind of isolated from the rest of the world at the time,
但据认为，那时位于现撒哈拉以南非洲的生物是与世界其余部分相隔离的，
and therefore can't tell us much about major groups like titanosaurs. But this new fossil suggests otherwise.
因此它们无法告诉我们关于那些大型群体，如泰坦巨龙的信息。但是这一新化石则另有结论。
It was found in a quarry along the Mtuka River in southwest Tanzania. They're calling it Mnyamawamtuka moyowamkia.
这块化石是在坦桑尼亚西南部Mtuka河沿岸的采石场内发现的。他们称之为Mnyamawamtuka moyowamkia。
That's a combination of Swahili words which roughly translate to "beast of the Mtuka with tail hearts."
这是斯瓦希里语单词的组合，译为“带心型尾骨的Mtuka野兽。”
That last bit references the heart-shaped structures in the tail vertebrae they found.
最后两个词是参考了尾椎处的心型结构。
And the best part is, they found well-preserved partial remains of every body region, including numerous vertebrae, ribs, limbs, and teeth.
最棒的地方是他们发现了每个体部位的局部遗骸都保存完好，包括无数块尾椎、肋骨、四肢和牙齿。
That makes it one of the most complete titanosaur fossils ever found.
这是至今所发现的最完整的泰坦巨龙化石之一。
All of that means it could shed some much-needed light on how this group of dinosaurs first evolved and diversified.
所有这一切都意味着这能够解释这种恐龙的首次进化以及衍生。
For example, its teeth seem to be intermediate in shape between earlier sauropods and the peg-like teeth found in titanosaurs later on.
例如，它的牙齿形状介于早期蜥蜴类动物牙齿形状和在后期泰坦巨龙身上发现的钉子状牙齿之间。
Small details like these can help scientists piece together the relatedness of different fossils to make an evolutionary tree.
类似的小细节可以帮助科学家们将不同化石的关联性拼凑在一起以制成进化树。
And the tree in this paper suggests this region of Africa wasn't as cut-off as paleontologists thought,
该篇论文中的进化树表明非洲的这个区域并不像古生物学者以为的那么与世隔绝，
and was likely a prominent area of early titanosaur evolution. That means more secrets may lie waiting for discovery in places like Tanzania.
这个区域可能是早期泰坦巨龙进化的主要地区。这意味着像坦桑尼亚这样的地方可能还有更多有待发现的秘密。
So hopefully, future expeditions in Africa can paint an even clearer picture. And this is just one of two new sauropods in the news.
所以在非洲的未来探索可以描绘出一幅更加清晰的图画。这只是新闻中的两种新蜥蜴类动物之一。
The second one has sparked a bit of controversy since it was published in the journal Scientific Reports on February 4th.
自2月14日《科技报告》杂志出版以来，第二种蜥蜴类动物就引发了一些争论。
It's a roughly 140 million-year-old dicraeosaur, part of a family of sauropods
它是一只约1.4亿年前的恐龙，属于蜥蜴类动物家族的一支
that had their heyday around the late Jurassic and early Cretaceous periods, just before the titanosaurs really took over.
它们的全盛时期是在侏罗纪后期以及白垩纪早期阶段，正好是在泰坦巨龙真正接手之前。
They're smallish sauropods—you know, only like 20 meters long.
它们是体型较小的蜥蜴类动物，仅有约20米长。
But their real claim to fame lies in their forked vertebrae, which give them a ridge of spines down their necks.
但是它们真正出名的原因在于它们的成叉状的椎骨，它们的脖子上有脊状尖刺。
Hence, the name of the new discovery: genus Bajadasaurus, because it was discovered in the Bajada Colorada region of Argentina,
因此这一新发现被称为：Bajadasaurus属，因为是在阿根廷巴塔哥尼亚地区发现的，
and species pronuspinax, which means "forward facing spines."
并且pronuspinax指的是“面朝前的尖刺。”
This specimen wasn't as complete as the titanosaur— they found most of the skull and jaw bones and one neck vertebra.
这一标本不如泰坦巨龙完整—他们发现了大部分头骨和颌骨以及一块颈椎。
But that neck vertebra has some glorious spines: a pair of them, reaching 58 centimeters in length,
但是这块颈椎上有一些尖刺：一对长58厘米的尖刺
which researchers believe arched toward the animal's head.
研究人员认为这些脊柱是朝着动物头部弯曲的。
They say that suggests this dinosaur had a huge, spiky, front-facing mohawk that ran all the way down its neck.
他们表示这表明这只恐龙留着巨大、尖尖的、朝前的马希坎发型，顺着脖子延伸。
That might seem weird, but remember, spiny vertebrae are what these dinos are known for.
这可能有点奇怪，但要记住，带刺的椎骨是这些恐龙出名的原因。
Just look at Amargasaurus, who sported its own respectable set of neck spines.
看看阿马加龙，它们炫耀着自己脖子上的一套尖刺。
The mystery here is what those spines were there for.
此处的谜团是那些刺是用来干嘛的。
Some think they could be for a pair of sails that helped regulate temperature, kind of like the spines in Dimetrodon.
一些人认为它们是帆，帮助调节温度，有点像是异齿龙的尖刺。
Others think they might have supported fatty humps like you see in bison and camels.
其他人认为它们可能充当充满脂肪的驼峰，就像是北美野牛和骆驼一样。
And of course, there's always the possibility that they were some kind of mating display.
当然，这也有可能是吸引异性的装扮。
Maybe a couple of padded crests were their version of a tricked-out Tinder profile.
或许一对填充的脊突是它们在tinder上的个人资料简介。
But the researchers behind this study are backing a different theory: they say they were there to defend against predators.
但研究人员认为这项研究支撑了一种不同的理论：他们说这些尖刺是为了防御捕食者。
When they lowered their heads to graze, the spines might have stuck out at just the right angle to skewer any attackers.
当它们低头吃草时，尖刺适当突起以刺穿任何袭击者。
And the idea isn't completely random.
这种说法并非胡言论语。
There is at least one living species that has pointy neck bones that are also thought to be protective: the potto, a slow-moving African primate.
至少有一种现存物种所拥有的尖尖的颈骨也被认为是起保护作用的：树熊猴，一种行动缓慢的非洲灵长类动物。
But the researchers' conclusions have received a fair bit of criticism.
但研究人员的结论受到了不少批评。
One problem is that it's not clear the animals had protection anywhere else. So predators could, you know, just attack from behind.
一个问题是尚不清楚动物身上的其他任何地方是否拥有这种保护机制。所以捕食者可以从后面袭击它们。
Also, the spikes are very close to the spinal cord, so they'd have been risking paralysis every time they impaled something that thrashed around.
还有，尖刺距离脊髓非常近，所以它们每次刺穿周围某物时都有瘫痪的风险。
But perhaps the most obvious complaint is that the authors made sweeping conclusions about their necks based on very little data.
但最明显的抱怨是作者们关于它们脖子的全面结论是以很少的数据为基础的。
Remember, all we have is one vertebra bearing one pair of spikes.
我们所有的不过是一块带有一对尖刺的椎骨。
To conclude that this species had a full set of forward-facing spikes and that it used them for protection might be pushing it a little.
得出这种物种拥有一套完整的、朝前的尖刺以及这些尖刺起保护作用的结论似乎有些勉强。
That's one of the biggest challenges to studying a long-dead species.
其中最大的挑战之一是要去研究一个久逝的物种。
Paleontologists often have to piece together an entire animal's biology and behavior from a few bones encased in rock.
古生物学者经常需要从被岩石包裹的几块骨头中拼凑出完整的动物生物和行为。
Fossils can tell us some really incredible things. But they keep their secrets sometimes, too.
化石可以告诉我们一些非常惊人的事情。但有时它们也留有自己的秘密。
It's impossible to be 100% certain how the vertebral spikes were used without going back in time to see them firsthand.
不去那个时代亲眼看看就不可能百分百确定这些脊椎尖刺的用途。
But, if we find a lot more fossils of this species and its relatives, we might be able to rule out some ideas.
但是如果我们发现了更多这一物种及其近亲的化石，那么我们或许能够排除一些想法。
The good news is that we're finding more new dinosaur species than we ever have before, at a rate of around 50 a year.
好消息是我们所发现的恐龙新物种比以前更多，速度比为一年约50种。
So, who knows what evidence is waiting to be unearthed! Thanks for watching this episode of SciShow News!
所以谁知道还有什么样的证据等待着我们去挖掘呢！感谢收看本期《科学秀》！
And an extra special thanks to our President of Space, Matthew Brant.
特别感谢Space的董事Matthew Brant。
Matthew, we think you're DINO-mite! And we really appreciate your continued support.
Matthew，我们觉得你就是DINO-mite！我们真的非常感谢你的一贯支持。
If you want to be President of Space, or just support us so we can keep making videos like this one,
如果你想像Space的董事一样或是仅仅想支持我们让我们可以制作这样的视频，
head on over to Patreon.com/scishow to learn more about becoming a patron.
请登录Patreon.com/scishow了解如何成为我们的赞助人。
And be sure to swing by every Friday to keep up to date on the latest science news!
每周五一定要来观看最新的科学新闻！
