(单词翻译:单击)
June was a really bad month for North Atlantic right whales. Of the remaining 411 individuals, 6 died.
对于北大西洋露脊鲸来说，六月是一个非常糟糕的月份。剩余的411只中有6只死亡。
That's almost one and a half percent of the entire population gone in a month, which is kind of alarming. And mostly our fault.
这相当于整个种群的约1.5%在一个月内消失，这有点令人担忧。而且大部分还是人类的过错。
If we can't fix what we're breaking, we're looking at the functional extinction of these whales in just a few years
如果我们不能修复我们正在破坏的东西，我们将看到这些鲸鱼在短短几年内功能性灭绝
and their total disappearance not long after.
用不了多久它们就会完全消失。
That would make them the first whale to go extinct as a result of commercial whaling.
这将使它们成为因商业性捕鲸而灭绝的首种鲸类。
North Atlantic right whales are already one of the most endangered whale species in the world.
北大西洋露脊鲸已经是世界上最濒危的鲸种之一。
That's because they used to be incredibly popular with commercial whalers.
这是因为它们曾经非常受商业捕鲸者的欢迎。
Hence the name, they were considered the "right" whales to target, so they were hunted to near-extinction.
因此这个名字，它们被认为是“正确的”目标鲸鱼，所以它们被猎杀到濒临灭绝。
But then, governments stepped in to protect them, and things started to look up.
但后来，政府介入保护它们，情况开始好转。
In fact, in the early part of this century, their numbers seemed to be climbing.
事实上，在本世纪初期，它们的数量似乎在攀升。
But that all changed around 2010. And the reason why is pretty clear.
但在2010年左右，一切都变了。原因很清楚。
Research published last month found that we've lost an average of 5.3 whales per year since 2009
上个月发表的研究发现自2009年起，我们每年平均失去5.3头鲸鱼
and that's not counting 2019 and June's Unusual Mortality Event.
这还不包括2019年和六月的异常死亡事件。
While researchers can't always tell the cause of death, most of the documented cases have been caused by humans:
虽然研究人员不知道所有的死因，但据记载案例，其中大部分都是人类引起的：
the whales either were hit by boats or caught in a fishing lines.
这些鲸鱼要么被船撞到，要么被钓鱼线缠住。
Of course, we'd like to see less whales die by our hands, but accidents do happen.
当然，我们希望看到更少的鲸鱼死于我们的手，但意外确实会发生。
So it's important to have an idea of how many human-caused deaths a population can withstand and still be sustainable.
所以重要的是要知道一个群体能承受多少起人类导致的死亡并且仍能继续延续种族。
That's a value called the potential biological removal or PBR.
这个值被称为潜在的生物去除或PBR。
And researchers have calculated it for North Atlantic Right Whales,
研究人员计算了北大西洋露脊鲸的PBR，
taking into account things like how many healthy whales are still around, their reproductive habits, and the availability of their prey.
考虑到了很多因素，如仍存活的健康鲸鱼数量、它们的繁殖习惯以及它们的猎物可得性。
The problem is, that number is estimated to be 0.9 whales a year,
问题是，这一值预估为每年0.9头鲸。
so, in the last decade or so, we've killed more than five times that number.
所以，在过去十年左右的时间里，我们已经杀死了这个数字的五倍多。
And there's a lot we still don't know, like, how many of them die outside of monitored areas,
还有很多是我们不知道的，比如，有多少死在了监控区域外
or how many already have human-induced injuries that will lead to their death later on.
或者有多少鲸鱼已经受到了人类的伤害，而这些伤害将导致它们以后的死亡。
For instance, there was one female that died fourteen years after being scarred by a propeller
例如，有一只雌性鲸鱼在被螺旋桨划伤14年后死亡，
because her scars were re-opened by pregnancy and became infected.
她的伤疤因怀孕而重新裂开并被感染。
Plus, the numbers are a bit skewed because we're more likely to find carcasses that have been struck by ships
另外，这些数字有些偏倚，因为我们更有可能发现被船只撞击过的尸体
those whales tend to be a little bulkier, so they float.
那些鲸鱼体型较大，所以它们会浮在水面上。
The whales that get tangled in fishing lines tend to sink, so their bodies are never found.
被鱼线缠住的鲸鱼会下沉，所以永远也找不到它们的尸体。
And not only are the whales dying too often, they're just not replacing their numbers.
鲸鱼不仅死得太频繁，它们的数量也没有得到补充。
There's only 90-100 adult females out there right now, and last year,
现在仅有90到100只成年雌性鲸鱼，并且去年
they gave birth to 7 new calves and that was considered a good year.
她们产下了7只宝宝，这一年被认为是不错的一年。
Researchers think they're struggling to reproduce
研究人员认为它们繁殖遇难
because our changing climate is messing with their usual feeding and pupping grounds,
因为气候变化正在扰乱它们通常的进食和繁殖场所
making conditions less favorable for the whale moms.
使环境对鲸鱼妈妈不利。
So basically, we've got a small population of whales that aren't making babies, and we're not-so-slowly killing them off.
所以基本上，有一小部分鲸鱼不生鲸鱼宝宝，我们并不会慢慢地杀死它们。
Both the US and Canada have implemented new laws in recent years to try to lower the number of human-caused deaths.
美国和加拿大已经在近几年实施新法试图减少人为死亡数量。
Some have helped, but clearly, there's a lot more work to do.
一些有帮助，但显然还不够。
Because ultimately, if we can't stop these losses from happening,
因为最终，如果我们不能阻止这些损失的发生，
it won't be long before these majestic animals disappear entirely.
要不了多久这些庞大的动物就会完全消失。
And other whales similarly decimating by hunting will probably suffer the same fate.
而其他同样被猎杀的鲸鱼可能也会遭受同样的命运。
In other news and really, there's no good way to make this transition,
在其他新闻中，没有一个好的方法实现这种转变，
research published in the Proceedings of the National Academy of Sciences this week
本周发表于《Proceedings of the National Academy of Sciences》的研究向我们展现了
showed us how bed bugs keep themselves from getting sexually transmitted infections.
臭虫如何防止性传播感染。
And the findings might just help us keep these pests from infiltrating our bedrooms.
这些发现可能会帮助我们阻止这些害虫进入我们的卧室。
Now, these STIs aren't like insect chlamydia, we're talking about infections that result from how these bugs have sex.
现在这些性传播感染和昆虫衣原体不一样，我们谈论的是由这些细菌如何交配而引起的感染。
Bed bugs reproduce through traumatic insemination.
臭虫通过创伤性授精繁殖。
The male literally stabs his reproductive organ through the female's abdomen and deposits sperm into her body.
雄性的生殖器官会刺穿雌性的腹部，并将精子注入雌性体内。
This process can happen every week if the female has access to a blood meal.
如果雌性吸到血，那么这个过程每周都会发生。
You see, males generally target well-fed females because they usually lay the most eggs.
雄性的目标通常是营养充足的雌性，因为它们通常产卵最多。
But sort of luckily I guess, female bed bugs are able to buff up their immune systems right before mating.
但我想幸运的是，雌性臭虫能够在交配前增强它们的免疫系统。
And what the researchers wanted to figure out was what triggers them to do this.
研究人员想要弄清楚的是，是什么促使它们这样做。
Turns out, it wasn't what they expected.
结果和他们所期待的不一样。
They thought the females might learn to ramp up their immune defenses after repeated stabbings.
他们认为雌性可能会在多次刺伤后学会增强自己的免疫防御能力。
But the team took two groups of adult virgin female bed bugs and fed them as much as they wanted once a week for three weeks.
小组分了两组成年雌性臭虫并给它们喂食，每周喂一次，连续喂三周。
And in the end, the ones stabbed by a glass needle to mimic traumatic insemination didn't have a greater immune response.
最终，用玻璃针模拟创伤性授精的臭虫并没有更强的免疫反应。
Instead, every bug beefed up their immune system after eating.
相反，吃完东西后，每只虫子的免疫系统都增强了。
That suggested the injuries the females receive aren't the driving factor,
这表明雌性受到的伤并不是驱动因素，
instead, the bugs just have this built in immune response to food.
相反，这些虫子天生就对食物有免疫反应。
But, the researchers still wondered if it was the act of eating itself, or something else.
但研究人员仍然想知道是进食本身还是其他的东西在起作用。
So they took immature bed bugs and fed some of them on a consistent weekly schedule.
所以他们取了一些未成熟的臭虫，按照每周固定的时间表喂养其中一些。
The others were fed at 5, 7, and 9 day intervals so their meals were inconsistent
其他的隔5天、7天和9天间隔进食，因此它们的饮食是不一样的
but averaged out to the same once-per-week frequency.
但平均都是相同的每周一次的频率。
Intriguingly, the group that ate every week ramped up their immune system way more
有趣的是，每周都进食的那一组在进食后和进食不相同的那一组相比，
after eating than the group with the varied eating schedule.
它们的免疫力更强。
And this made a big difference when they stabbed the bugs with bacteria-coated glass needles
当他们用涂有细菌的玻璃针刺虫子，模仿雄心虫子刺伤的伤口时
to mimic the wounds inflicted by male bugs,
就大不相同了，
those that were on a predictable feeding schedule had better survival rates.
那些按照可预测的喂养计划进食的虫子存活率更高。
So, it's not the food itself or a full belly, but the animals' anticipating that they'll get food
所以，不是食物本身或饱腹，而是动物将会得到食物的预期
that triggers their immunological preparation for mating.
触发了它们对交配的免疫准备。
And that knowledge could help scientists find better pest control strategies.
并且这一知识可以帮助科学家发现更好的害虫防治策略。
For example, they might be able to target female bed bugs when they're most vulnerable,
例如，他们或许能够在雌性脆弱的时候锁定它们
or uncover ways to make the bugs more prone to infection.
或是找出让虫子更容易被感染的方法。
And the researchers think that other insects might regulate their immune systems in similar ways,
研究人员认为其他虫子或许是以类似的方式调节它们的免疫系统，
so the more scientists learn about bed bugs, the better equipped they may be to fight all sorts of pests.
因此，科学家对臭虫了解得越多，他们可能就能更好地对付各种害虫。
Thanks for watching this episode of SciShow News!
感谢收看本期《科学秀》！
And thanks especially to our longest running President of Space, SR Foxley.
特别感谢Space总裁SR Foxley。
Your continued support really makes a huge difference to us! So does the support of all our patrons.
你的支持对我们有很大的影响！我们所有的赞助人也一样。
And if you join our patron community, you can get all kinds of exclusive rewards while supporting this free, educational channel.
如果你加入我们的社区，你可以获得各种度假福利同时也是在支持这个免费教育频道。
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前往Patreon.com/SciShow了解更多。
