Did one issue emerge as the top story? LiveScience invites you to vote on the most significant development in science and nature this year.

The Hurricane Nightmare Comes True

The busiest hurricane season on record brought the most intense Atlantic storm ever recorded and ran several days beyond its official Nov. 30 end, while scientists provided the first solid evidence that global warming might be fueling more powerful storms. These were all big stories in and of themselves, yet none will stick with us like the memory of Katrina, the most destructive storm ever to strike the United States and a long-predicted nightmare for resident of New Orleans. Nature's wrath forced scientists and officials to assess preparedness for other dramatic natural threats the country could face.

Evolution on Trial

Intelligent design, which posits that an intelligent being and not Darwin's theory of natural selection is responsible for some of the most incredible variations in species, exploded into public view. The Kansas school board voted against science, as did Alabama's when it voted to tell students that evolution is controversial. Eight families in Pennsylvania sued over the whole thing. And voters in one district ousted school board members for inserting religion into science classes. Meanwhile, scientific leaders broke a longstanding silence to defend evolution and discredit intelligent design as being unscientific, impossible to prove, and nothing more than cloaked creationism. Even the Vatican weighed in. The issue promises to permeate discussions of science and religion as long as the two exist.

The 10th Planet?

You might think the discovery of an object larger than Pluto orbiting the Sun would automatically be hailed as the long-sought 10th planet. Not so fast, many astronomers said. This new world is one of perhaps thousands out there that await discovery. Will we call them all planets? Should Pluto even be considered a planet? In a weird twist to the debate, the discoverer of the controversial object suggests we all ignore the scientific debate and let culture decide. One has to wonder if that's the sort of ambiguity science ought to promote.

The Apocalypse, or Just Mother Nature?

It's not your imagination: Natural disasters are becoming more common. But don't blame Mother Nature; we humans are moving in droves to disaster-prone coastlines and living in substandard structures. The magnitude 7.6-earthquake that struck Pakistan and killed upwards of 80,000 people was just another example of our inability to deal with events that are statistically normal. Christian televangelist Pat Robertson didn't let science cloud his vision, however, when he said the quake and a busy hurricane season might be signs that the Biblical apocalypse is near.

Signs of Life on Mars?

This story extends back to last year and looks like the sort of mystery that'll keep scientists scratching their heads for years to come. The air of Mars seems to contain pockets of methane in doses that should not exist. Perhaps it's the belchings of subsurface microbes, European astronomers said early this year. They support that view with new evidence for blocks of underground ice in the same region as the methane. The ice could be supplying the precious liquid water needed to support the biology, they figure. Other astronomers think the reasoning is very speculative, however.

Rebuilding Humans

The "Six Million Dollar Man." would appreciate the printable skin that's coming out of special inkjet printers now. The fictional bionic man, Steve Austin, was way ahead of scientists on synthetic body parts, but he'd be pleased to see the progress in 2005 on prosthetic limbs that humans might one day control with their minds. Monkeys were made to operate a robotic arm with just their thoughts via a computer attached to their brains. Further study found they treat the device as if it were a natural appendage. Meanwhile, the U.S. Military said further research into these devices would become a priority. No "fixing humans" story gained more attention this year than the first partial face transplant.

(Way) Back to Nature

In one of the year's more offbeat suggestions, scientists proposed introducing elephants, lions and camels to create a U.S. Ecological History Park that would return parts of the country to conditions similar to the distant past while also preserving animals that are threatened in Africa. In Siberia, a similar project is already underway. Scientists are working to restore a large area of wetlands and forest to the dry landscape that existed more than 10,000 years ago by re-introducing herbivores and predators they think will alter the biology and ecology. One goal: learn what caused the woolly mammoths to go extinct. Meanwhile, another group announced plans to search for frozen woolly mammoth sperm DNA, which they would inject into a female elephant; after several generations of offspring by controlled procedures, they would create a beast that is 88 percent mammoth. Amid all this, another team decoded part of the genome of an extinct bear!

Our Lowly Ancestors

A fresh analysis of two previously found skulls determined they're 200,000 old, making them the oldest known examples of our species. Yet fossil records indicate musical instruments, drawings, needles and other sophisticated tools didn't appear until about 50,000 years ago, suggesting Homo sapiens had a pretty lowbrow culture for 150,000 years. Well, evolution takes time. Another team found the fossilized remains of what they think is humankind's first walking ancestor, from 4 million years ago. Other research confirmed that the oldest human ancestor, from the time when we split with the apes, lived around 6 million years ago. Oh, and you have to respect our relatively recent ancestors (the lowbrow folks) who we now know lived among 10-foot-tall gorillas that have since gone extinct. Maybe they were so busy running they had no time to paint or create alphabets.

Total Neanderthals

Anthropologists scrounged around museum halls to put together bones from various specimens to make the first Neanderthal skeleton. And the result surprised them: "As we stood back, we noticed one interesting thing was that these are kind of a short, squat people," said Gary Sawyer of the American Natural History Museum in New York. "These guys had no waist at all-they were compact, dwarfy-like beings." Meantime another team announced plans to reconstruct the Neanderthal genome from fossil fragments.

Super-Earth Discovered

Astronomers expect to eventually find many Earth-sized planets around other stars. But technology can't spot such small objects yet. Pushing the limits of existing methods, researchers detected a world just 7.5 times the mass of Earth orbiting another star and said it must be rocky. This year marked the 10th anniversary of the discovery of the first extrasolar planet around a normal star, and astronomers have gathered enough data on about 150 planets since then to say, in the words of Geoff Marcy, "I imagine most stars have terrestrial planets. It seems hard not to form them."

The Reality of Myths

Finally, visual proof of the longstanding myth. Japanese scientists got the first images of a giant squid in its natural environment. In California, meanwhile, hundreds of huge squid washed ashore. And another new species of large squid was captured on video. Otherwise, it was a typical year for creatures of myth (some of which, like the squid, turn out to be real, by the way), with Bigfoot fans staging a conference and scientists exploring claims of a giant lake monster in Canada. Seems even scientists like a good tale; one team found an ancient sea creature that looks to be part crocodile, part T. rex and dubbed it Godzilla.

Decoding the Software of Life

It was a big year for genome decoding. Scientists deciphered the DNA of man's best friend, along with humankind's closest relative, the chimp. Such findings are becoming so routine, however, that you might not have even noticed that the genome of rice was revealed, too. The ongoing investigation into our own DNA, meanwhile, revealed that identical twins are not so identical. Other researchers reported that about 9 percent of human genes are undergoing rapid evolution.

Shrinking the Invisible

In the world of nanotechnology, which is measured in molecules, engineers crafted some nifty miniature machinery this year. Different teams created the world's smallest car, motor, robot, refrigerator and fountain pen. One hope is that these tiny machines, invisible to the human eye, will one day be used to deliver drugs into cells, perhaps to destroy cancer or cure other ills. Technology tasks are envisioned too. In one nifty breakthrough, researchers merged microbe and machine for the first time, creating gold-plated bacteria that sense humidity.

Birth of a Black Hole

An explosion 2.2 billion years ago, whose light just arrived at Earth this year, was detected and then monitored by an unprecedented array of telescopes on the ground and in space operated by astronomers furiously exchanging emails. Within moments, the scientists suspected they had seen the birth of a black hole as it happened (well, except for that previously mentioned time delay). The event was triggered by the merger of two neutron stars, the thinking goes.

Advancing Humanoids

A longstanding goal of robotics is to make them more humanlike. Several small steps in that direction were achieved this year. One team developed robots that walk like us. A NASA researcher announced robotic skin that can feel things. Another bot looks so humanlike you might want researchers to stop this trend. Then again, who could complain about a robotic bartender that pours and listens.

Copycat Cloning

Making replicas of animals has become so routine since Dolly the sheep in 1996 that the story about Snuppy, the first cloned dog, didn't have the bite it might once have had. Meanwhile, Dolly's creator this year got a license to clone humans. Apparently one day your double can walk your dog's double. All the advances in mucking with the formulas for life led to an interesting clinical trial in which parents will pick the sex of their babies (other research shows most women would choose if given the option, but overall there was no clear preference). The year ended on a notable down note (dare we say duplicitous?) when a South Korean cloning pioneer admitted the ethically questionable practice of using some of his own employee's eggs and then admitted there were errors in his landmark science paper about having cloned human stem cells.

First Photo of an Extrasolar Planet?

A series of announcements about the possible first picture of a planet around another star ended up in a debate that has yet to be resolved. The pictures are real, but astronomers can't agree on the masses of the objects in the images or, for that matter, how to state the difference between large planets and small stars. We'll have to wait for history to tell us if this was a big story or not.

Toward Immortality

"I think it's reasonable to suppose that one could oscillate between being biologically 20 and biologically 25 indefinitely." That's what eccentric researcher Aubrey de Gray, who thinks aging can be cured, told LiveScience in an interview this year. De Grey also runs the Methuselah Mouse prize for breakthroughs in extending the lives of mice, which researchers hope will spill over into progress to slow human aging. The purse of the M Prize, as it is called, grew beyond $1 million in 2005. As for hard science, one study showed that the buildup of mutated DNA triggers aging in mice. Another found stimulation of a certain gene in mice seems to delay bone weakening, artery clogging and loss of muscle fitness. Modern medicine is already allowing life expectancy to creep up, and it hit an all-time high in America this year. Ray Kurzweil, a computer scientist and writer, explained that his plan to live forever involves not tailgating, but taking 250 supplements and drinking lots of alkaline water and green tea.

Protecting Ourselves

Some day, scientists have been telling us for some years now, we'll have to deal with an incoming asteroid or comet that would destroy civilization at worst or wipe out a city at least. Big impacts have occurred before, and there will be more. But we don't know enough about space rocks and their composition to plan properly for deflecting or destroying such a menace. Turnabout proved to be fair play when NASA's Deep Impact mission slammed a probe into Comet Tempel 1 on the 4th of July. The upshot? This comet was fluffy, unlike others that have been studied up close. Meanwhile, a group of astronauts and scientists prodded NASA to visit asteroid Apophis, which has a slight chance of hitting us a few decades hence. NASA's response: A purely scientific mission might be considered, but we have plenty of time to mount a diversion if further observations show this thing would really hit.

Global Warming Heats Up

We can all stop arguing about whether the climate is changing. Evidence is overwhelming, from shrinking glaciers to melting polar ice caps and seas rising at twice the rate of the pre-industrial era. Animals are changing migration and mating patterns; in the North, 125 lakes disappeared; river ice is melting sooner in spring. This year is expected to be the hottest, stormiest and driest on record. The big remaining question is how much of the trend is natural (scientists admitted they know little about the Sun's role!) and how much is exacerbated by greenhouse gas emissions. Meanwhile, a host of studies made dire predictions about the inevitability of rising temperatures and swamped coastlines over the next century. Nasty side effects were predicted: more intense rainstorms; worse droughts; stronger hurricanes; increased allergies; ice-free arctic summers; and economic costs. A couple novel solutions were proposed: altering airline flights and lofting a ring of miniature satellites to shade the equator. Tempers rose in 2005, too, with the year closing on a low note from the perspective of more than 150 nations who pledged to do something about the problem, without the support of the United States or China.

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