What is the most serious danger against our world?

Answer 1

I like and agree with the answers indicating people or humans.
We as humanity have become like vermin to this world.

My answer is overpopulation by the human species.

We as humans, seem to be quite good at using and abusing anything we touch when considered as an overall population.
Not to say that there are not good things about humanity.
But as the old adage says: Too much of a good thing; isn't a good thing!

Answer 2

The Copenhagen Consensus Center (CCC) analyzes the world's greatest challenges and works with any organization concerned with mitigating the effects of these problems.
their ranking can be found here
http://www.copenhagenconsensus.com/Default.aspx?ID=728

On Lawrence Lessig's blog, Philosopher and Federal Judge Richard Posner responded to this attempt

"One commenter corrected my statement that the Copenhagen Consensus had ranked global warming last on the list of the world’s ills. For one thing, the list is very incomplete (more on that below). For another, what the conferees were asked to rank were solutions, not problems. They were given three solutions to global warming, including the Kyoto Protocol, and didn’t like any of them.

But what a weird procedure! Not to ask the economists to rank the best solutions they could think of, but instead give them the solutions and tell them to rank them. So by his choice of solutions, the organizer could pretty much predetermine the results.

Another commenter asked: what makes me think global warming is the world’s most serious problem? Nothing; but it’s not what I think. The Copenhagen conferees were given a short, rather eccentric, list of problems; they were not asked what they think the most serious problems are. The list includes not only malnutrition, AIDS, and malaria, but also such things as water purity and trade barriers. In that list, it seems to me global warming is the most serious problem, though it doesn’t follow that we should adopt either the solutions put to the conferees, or any other solution: that depends on costs and benefits. Global warming would be very costly to arrest, so maybe we shouldn’t do anything about it, although for reasons I can’t adequately explain here but are spelled out in my book, I think we should.

If I were asked to list the greatest threats to the world, I would include global warming, but would add bioterrorism, nuclear terrorism, nuclear proliferation, biodiversity loss, cyberterrorism, nanotechnology, artificial intelligence/robotics, and asteroid collisions.

Asteroid collisions? I anticipate teasing comments asking me whether I’m also worried about invasions of aliens from other galaxies. (I’m not.) In fact the probability of a catastrophic asteroid collision, while small, has a greater expected cost than the $4 million that is all that NASA is spending a year to map NEOs (dangerous near-earth objects, i.e., asteroids whose orbits intersect the earth’s orbit. For a good discussion, see the report of the Task Force commissioned by the U.K.’s minister for science. It was less than a century ago that an asteroid a mere 60 meters or so in diameter exploded over Siberia with the force of a hydrogen bomb. Fortunately, the only casualties, so far as anyone knows, were the local reindeer. Maybe the next asteroid will explode above Los Angeles, sparing the reindeer. Of course that’s unlikely; cities occupy a minute fraction of the earth’s surface. But a slightly larger asteroid, wherever it landed, could inflict tens or even hundreds of millions of casualties from tsunamis, fire storms, shock waves, and dense clouds of debris that could block photosynthesis and even trigger catastrophic global warming.

A survey of global dangers, ranking them by expected costs, and analyzing cost-justified responses (if any), would be a great project, and one in which economists would play a key role. The “Copenhagen Conference,” however, strikes me as a parody of such an undertaking."

Answer 3

Killer Bees

Look at their progress from Brazil to North America in just 2 decades. Killer Bees have a snowball affect growing exponentially. In another 3 decades they will cover the world.

Answer 4

relegion is the most dangerous in the developed countires
disease is the most dangerous for the developing countires
starvation is the most dangerous in the undeveloped countries

Answer 5

People

Answer 6

Human Beings.

Answer 7

Red Chinese colonialization of North America and Austrailia

Answer 8

Democrats
Terrorists
Muslim extremists

Answer 9

world powers an there nukes in general people are

Answer 10

my opinion would be an EMP or exploding a nuke a couple miles up so that we would lose all our technology.. iran and the terrorists trying to get their hands on these weapons could literally send us back to the horse and buggy days.. and leave us sitting ducks for an attack..