Nameks can be used very easily as many of their warriors and children left their planet after the comet hit, and with the colonization of New Namek, the race has survived.
The last 3 paragraphs detail briefly the story line of the later seasons of the Dragan Ball series and the first few seasons of the Dragon Ball Z series. For a more detailed description go to the official Dragon Ball Z website.
The Nameks were a peaceful race that inhabited a planet 4339 light-years away from Earth. At one time the Nameks had created a prosperous civilization that covered their planet. Their civilization was built on magic and cooperation between the many different cities that housed their population. Each Namek community had a leader, but all Nameks were subservient to the one they referred to as the Father. The Father was always an ancient and extremely powerful Shaman who controlled the mystical Dragon Balls. Nameks went to him for guidance and judgment, but the Father rarely interfered with the day-to-day operations of the other Nameks.
This all changed when a rogue comet crashed into the surface of Namek. The impact from the comet changed the orbit of the planet and the climate across the entire planet rapidly changed. Many Nameks died from the extreme weather before the climate stabilized. The orbit of the planet and of its two moons shifted and the planet moved closer to the three suns at the center of the Namek star system. This would have raised the temperature of the planet, but fortunately the dust from the comet in the planet’s atmosphere prevented the planet from being cooked by the constant heat from the stars.
The few Nameks, barely more than a hundred, that survived gathered together at the location of the Father’s residence. The current Father, a Namek named Guru, purposed a plan to send all of the remaining Namek children out into space so their species could survive on other worlds. The other Nameks agreed and with Guru’s help they rebuilt some of the damaged spaceships and sent their children off into space. Single a single Namek can create a child, they knew that some of their children would survive on other worlds and continue their race. The remaining Nameks gathered into a single village and began to adapt to life on their changed planet. The population slowly grew and Guru personally trained all of the young Nameks to become powerful warriors. Most of these warriors left the planet soon after becoming adults to spread the population even further, but some stayed and the population grew to six different communities scattered across the planet. Guru’s greatest and last student, a Namek named Nail, remained at Guru’s house and became the Father’s protector. Guru had decided that he wanted Nail to take his place as the Nameks' Father; Nail would have been the first Father not to be a shaman.
One of the Namek children sent after the comet strike arrived on Earth. The child, named Piccolo, grew and developed incredible magical powers, but he also wished to eliminate the evil that he felt within his own soul. Piccolo purged his entire body of evil and he changed his name to Kami, but the evil formed its own body and became known as Piccolo-Daimao. Kami went on to become the Guardian of Earth and created a set of Dragon Balls for the planet, but Piccolo-Daimao only wanted to conquer and destroy his enemies. Unfortunately, through the link that two beings shared, they could not kill each other, for if one died, the other would too, so they worked against each other for many years using intermediaries. The Saiyan child Goku and Piccolo-Daimao were enemies and when Goku finally defeated him, Piccolo-Daimao was able to create a child named Piccolo just before he died. Piccolo shared the link to Kami, so the death of Piccolo-Daimao did not cause Kami to die. Piccolo also grew to become a rival of Goku, but when more powerful forces came to destroy the Earth, Piccolo joined forces with Goku to fight them and eventually died to save Goku’s son, Gohan.
When Piccolo died, Kami died as well and the Dragon Balls on Earth stopped working. To resurrect their friends, the Saiyan Gohan and and a martial artist named Krellin traveled to the planet of Namek to use the Dragon Balls located there. But the Saiyan prince Vegita and Frieza had already traveled to the planet and were also looking for the Dragon Balls. Each of the six Namek villages had been given a Dragon Ball and either Vegita or Frieza destroyed each village in their search for the seven Dragon Balls. One of the survivors of a village was a young Namek boy named Dende. Eventually all of Nameks were killed except for Guru, Nail, and Dende. Nail was badly wounded by Frieza but merged with a revived Piccolo to make him stronger, Guru died shortly after the Dragon Balls were used, and Dende was killed by Frieza to prevent him from helping Vegita and Gohan.
When Piccolo was returned to life, Kami was also revived and with his assistant, Mr. Popo, Kami collected all of the restored Dragon Balls on Earth and used them to revive all of the Nameks killed by Frieza and brought them to Earth. Eventually Frieza was defeated, but the planet Namek was destroyed, the surviving Nameks chose a new Father and traveled to a new planet they named New Namek where they began to rebuild in peace. Piccolo and Kami continued to play an important role on on Earth and Dende eventually became the new Guardian of Earth.
Nameks have green skin and short antennas that come out of their forehead, and they have natural plates of armor on their chest, back, and parts of the legs and arms. Nameks have no body hair and their eyes are usually white with a small, black pupil. Nameks vary in size from 5’6” to 8’ (1.7 to 2.4 m) and they do not need to eat food, but they require three times as much water as a normal human. It is theorized that Nameks evolved from plants, which is evident from the fact that their species has only one gender and the fact that they require only water. However, even if the Nameks did originally evolve from plants, they are so far removed from their origins that they have lost nearly all of the benefits of having a plant origin.
Nameks appear all male, but in fact, their bodies contain both male and female reproductive organs. Every five years an adult Namek can create an egg that will eventually develop into a Namek child. The egg is released through the mouth and does not need any special attention in order for it to hatch other then not being placed in an environment where an exposed Namek would die. The egg will hatch by itself three months after it was released from its parent and the child will contain most of the memories of its father. In some cases this allows a Namek to have memories from thousands of years ago, but this rarely happens and usually only with the direct children of a Namek Elder or the Father. Nameks mature quickly and 10 years after they have hatched they are fully mature adults capable of producing offspring.