标签：BBC地平线 相关文章
Over 2 years of study, Randolf has shown that these doses neonicotinoids do affect bees' higher cognitive processes, especially their memory of the landscape around them.-We tested about 200 bees, both controlled bees and pestcide-treated bees, and w
探索与发现2013年
-There are at least pieces of evidence which show really serious impacts from levels of neonicotinoids that bees, wild bees could be exposed to in wild environment.And the arguement against the ban was laid out by one of the pesticide manufacturers.
探索与发现2013年
-How does it work then? There are millions of insects out there in the air you sweeping. You target specific individuals.-That's right, so we have an individual honey bee which will be carrying this very small fine container on its back. And that's t
探索与发现2013年
Thankfully the micro s* can be treated, but when you look more closely, you can see what could be the real cooperate, a virus.-Here are the virus particles. We are looking at these particles at about 40,000 times magnification. Obviously, they will b
探索与发现2013年
And here it is, the flight of the humblebee. This is what's called its exploratory path. The routine takes its circles around the hive for the first time. Over several days it's built up a mental map more than 10 square kilometers around the hive. Th
探索与发现2013年
The first step is to try to really understand the enemy. Poor little bee. So Jean, where is it on this bee that? Ok. I think if you looked even with a naked eye. Just to the side of the abdomen. Yes, oh, on the belly there. That grape red colored. Ok
探索与发现2013年
The thing is bees are very sensitive to the weather. If the temperature falls below fourteen degrees or if it rains they just won't leave the hive. The nectar of the flowers is also temperature dependent. So if it's cold, there will be less nectar an
探索与发现2013年
-So you had a tough year.-We have got that, yeah. It's been an incredibly bad winter, and that's companed with probably the worst summer we ever have had as well, last year. -So these boxes should be out, full of bees working. -Yeah, they have been b
探索与发现2013年
When you consider the Earths history stretching over billions of years, its clear that meteorite impacts, far from being unexpected, are just a normal part of the life cycle of our planet. But that is not how they seem to us. The Chebarkul meteorite
探索与发现2014年
It came in in the daytime sky out of the Sun. Weve got telescopes looking out there for these objects, but they only work at night. Radar doesnt help either because to really use radar to find these objects above the atmosphere, you have to know exac
探索与发现2014年
Approaching from beneath the planet, asteroid 2012 DA14 passed inside the orbit of our geostationary satellites before heading off to the north. This asteroid had been successfully tracked for a year. And despite its proximity, scientists knew that i
探索与发现2014年
There it is! Yep. Its about 90 kilometres up, at that stage, travelling at 17.5 kilometres per second. Using the different camera positions, scientists have pinpointed the exact position at which the meteor entered the atmosphere. And by tracking the
探索与发现2014年
Most of the damage from an explosion like this is actually the blast wave. Its the very high winds. Mark created a simulation to see what size an asteroid would need to be to be able to generate such destructive power. In this simulation I include mo
探索与发现2014年
Really, its a balance between the size of the object, its speed into the atmosphere and critically the altitude at which it explodes. Too high, if its too small and it explodes too high, the shockwave has little effect on the ground. If its quite low
探索与发现2014年
Down on the ground, the scale of impact is even more breathtaking.The crater is more than 1000 meters across and nearly 200 meters deep.The forces here were enoumous.The impact on this solid rock into this pulverized mochi,just bustled in your hand.Y
探索与发现2014年
So this was serial number one. It was built during the Apollo time. I guess because they thought there would be several of them made, but this is the first one and the last one and is the only one like it in the world. This is NASAs Vertical Gun Rang
探索与发现2014年
Oh, perfect, perfect, perfect. Now were seeing the fireball come in, its brighter than the Sun and then, Kapow, it hits the surface. Jeez! This whole region, downrange, would have been incinerated. It would have been incinerated just by this plasma,
探索与发现2014年
Look at the size of this! This is magnificent! That is beautiful. This cave may be stunning, but it provides the evidence for one of the greatest catastrophes in the Earths history. And that water, its so clear! Lower the gear, please! Theres actuall
探索与发现2014年
But there is a downside to Jupiter. It can also deflect asteroids into orbits that cross the Earths path. The Chelyabinsk meteor appears to be one of these typical Earth-crossing events. The likelihood is that it was thrown out of its regular orbit b
探索与发现2014年
This summer, I set out to get to the bottom of a story thats captured the headlines. And this one, Ive got some experience myself, because Im also a beekeeper. There, is that good? Yeah, its perfect. Ok, I hate squeezing like that. I met some scienti
探索与发现2013年