No list of the year?s achievements would be complete without including some of the scientific discoveries and medical breakthroughs that made headlines. VOA?s Carol Pearson has a look back at the remarkable developments in science and health.
The most amazing breakthrough was the discovery that potentially life-supporting water was once present on Mars. NASA's twin rovers, Spirit and Opportunity, have been exploring the red planet since January of 2004. NASA says recent data beamed from Spirit shows the presence of a mineral that can only be formed in pools of liquid water.
Opportunity also discovered evidence of ancient cycles of flooding and drought.
Dr. Steven Squyres is the mission's main scientist. He comments on the mission, "This was a habitable environment on Mars. This was a shallow sea. It is a salt flat. Now, we don't know that life was there, but we have an environment that was very suitable for life." he said.
The findings suggest a wet, warm Mars where life could have formed billions of years ago, at the time when life was developing on Earth.
In another significant breakthrough, astrophysicists discovered the first known pair of pulsars, spinning neutron stars that shoot out jets of radiation. Further studies of these whirling objects may provide the most stringent examination yet of Einstein's general theory of relativity.
On Earth, scientists working in a cave on the remote Indonesian island of Flores found the bones of the smallest human species. Australian Professor Bert Roberts, who was on the discovery team, dubbed them "hobbits," because they were only about a meter tall.
"Here is one of the arm bones of the hobbit," says Professor Roberts. "You can see it is half the size of my arm, and everything else was half size on the hobbit, half our height, and until this discovery last year, no one had imagined that humans could be that small in the recent past." he said.
These tiny humans are formally called Flores Man (Homo Floresiensis). They appear to have lived as recently as 18,000 years ago and Dr. Roberts believes they may have lived on the island until the 16th century.
Researchers in South Korea made headlines worldwide in 2004 when they announced they had cloned a human embryo. It was the first evidence that this technique could work with human cells. The researchers said they wanted to produce embryonic stem cell lines that could help scientists understand complex diseases or eventually produce genetically matched replacement cells for patients. Since the stem cells would have the patient's own DNA, it would lessen the chance of rejection.
Disturbing news about the decline of species diversity came from large studies of amphibians, butterflies, plants and birds. Audubon Society spokesman Bob Perciasepe identifies the main problem as, "Habitat destruction is definitely the number one issue that we deal with on most of these species," he said.
A Stanford University scientist says by the end of this century, about 10 percent of all bird species will probably be extinct, killed off by habitat loss, hunting and climate change. The Stanford study says loss of these species will affect people, as the birds disappear that pollinate crops, prey on pests and eat animal carcasses.
In medical developments, new efforts were made to provide medicines for the world's poor. Joint ventures by wealthy countries, foundations, health experts, pharmaceutical companies and other groups promoted several initiatives, including a malaria vaccine trial and efforts to provide anti-HIV drugs. The World Health Organization has set a goal of getting anti-AIDS drugs to three million people in the developing world by the end of 2005.
In trials in Mozambique, a vaccine developed by GlaxoSmithKline prevented nearly 60 per cent of cases of severe malaria in children. The pharmaceutical company has been trying to develop a vaccine for 20 years.
Joe Cohen, GlaxoSmithKline's director of research and development, hailed the trial in Mozambique said "It's been a great success. Actually, the results are such that we believe it's a breakthrough in the field of malaria vaccine development."
Further studies will be needed before the vaccine can become available sometime in 2010. In other news, drug-maker Merck pulled painkiller Vioxx off the market because the drug was found to double the risk of heart attack and stroke.
The bird flu broke out last January in southeast Asia and caused millions of chickens to be exterminated. But health experts says the region's worries are not over. They say avian influenza has entrenched itself in much of Asia, and is unlikely to disappear soon.
This year saw two major outbreaks of a deadly strain of bird flu virus in Cambodia, China, Hong Kong, Indonesia, South Korea, Laos, Malaysia, Thailand and Vietnam. Less virulent strains hit other countries. The virus that causes bird flu spreads rapidly and has mutated to a form that can be carried by pigs and cats.
The World Health Organization warns that 2005 may see even worse outbreaks of bird flu as conditions are ripe for a devastating pandemic among birds and, potentially, people.