Andromedans, are, of course, from the Andromedan Galaxy... But way back when they lived there, they didn't call themselves that. Andromeda, of course, was a name given by the humans to classify a galaxy that was many, many lightyears away.
The Andromedans left the galaxy years ago, in search of a new home. They traveled on huge spacefaring vessels called Arks. Generations were born on the arks, and those same generations grew old and died. The stories of their ancestors were passed down through generations, though along the way, they forgot what it was exactly they called themselves... To each other, they were just people.
They set their course for a spiral galaxy they'd studied, far, far in the distance. The humans called it the Milky Way. There were many suns there, and many hopes for new homes. After a thousand-year voyage, the Andromedans were nearing their goal, and they were weary... And more than ready to live life planetside for the first time any of them could remember.
However, on their way to the Sol system, one of their Arks - a hatchery ship - was captured by the Spung and held for ransom... Either the super strong Andromedans agree to side with the Spung - become their slaves - or the Spung would crash the hatchery ship and a whole clutch of Andromedan eggs onto the nearest planet. The compassionate Andromedans couldn't let that happen... So they agreed to join the fight.
Somewhere along the way, no one is really sure how, the STARDOGS defeated the Spung and expelled them from the Sol system. The hatchery ship was rescued, and the Spung left the very confused Andromedans behind to face the wrath of the Earthers and the Rigelians. To everyone's surprise, peace was made with the Andromedans, and they were given a home near Proxima Centauri. Needless to say, since the war was only 12 years ago, there are a lot of people that still don't trust the Andromedans, even though they were forced to fight. A lot of people died at their hands...
Andromedans of a people are somewhat hive-minded. Most follow the god of Unity, called Yon... They are very methodical, and most don't differentiate from paths set out before them by the elders of their tribes. Those that show aptitude for independant thought are usually cast out of Andromedan society... Not maliciously, but with the hope that the independant ones won't cloud the hive-mind... And that they will be able to find a life of their own outside the hive. Castouts usually have a bit of trouble fitting in, as they are so used to people being bland, boring, and for lack of a better term, "nice", that they find it hard to adapt to the harsh realities of the outide world. The average andromedan that follows the Hive-Mind is content to take things as they come and adapt. The Castout isn't. The Independant Thinker prefers to ask questions, and learn things in different ways.
All Andromedans are bound together by a somewhat telepathic ability. Some find it strounger, some find it weaker, but all have some form of link. Castouts, of course, do as well, though their telepathy works in a different way. It makes them empathic, sensitive to the feelings of others. It is very unlike an Andromedan to want to intentionally harm another's feelings, though, of course, there are exceptions.
All Andromedans have incredible strength - this is likely because they came from a world with very strong gravity, and their strength is merely a byproduct of that. Be that as it may, and Andromedan that is fully grown can lift incredibly heavy equipment without batting an eye or breaking a sweat... Perhaps up to ten times their weight, and sometimes more. They also have very good hearing. Most Castouts have headaches until they learn to tune out unnecessary sound. As Harlan once said about Radu, "He can hear a spider spin its web from a mile away." Their navigational skill is also tied into their psychic ability. Andromedans make good navigators because they simply don't get lost. Some, of course, harness this skill better than others. As a final point, most Andromedans prefer to show as little skin as necessary... This is usually limited to face and neck for Identification, and female Andromedans will sometimes wear a semitransparent cloth over their faces. It seems to be a species taboo to show any skin.
Andromedans are considered mature adults at age ten, and they can reproduce around age fifteen. They are egg-layers... Each female lays two or three eggs that grow as they mature. Usually, eggs are transferred to hatcheries where they are born in anonymity. Most Andromedans don't know who their parents are, nor do they care. When they hatch, they are given a name by the Hatchery Master, and are also given a number designation. The first egg in a clutch to hatch might be called Kestrek-001. There are upwards of five-hundred eggs in a single anonymous clutch.
When the universes converged, an Andromedan Ark in patrol close to the Sol System was sucked in by the gravity of the black hole. As it tried to pull out, its internavigation and engine systems were fried. It was thanks to the flying skills of the Ark's navigator that the ship was able to set down on a half-Terraformed planet called LV-426... The Andromedans call it Second Andromeda. the ship is no longer space-ready, but it is heavily shielded from the Alien colony that lives on the planet. Since the forcefield's creation, no Xenomorph has entered. Those that have tried have all died... It is created so that only Andromedans and those they authorize may freely pass through it. Recently, attacks have stopped, though whether it is because the queen grew tired of losing her children or if the Andromedans and the Xenomorphs reach some sort of silent and mutual agreement, no one knows. The Aliens are still treated as hostile, but the Andromedans still leave them in peace.
No humans live on the planet anymore. There Terraformed Colony is empty. It seems that the planet belongs to the Andromedans to do with as they will... Though there's always the looming threat of Xenomorphs living practically next-door...
Isn't that fun! :D Now go app an Andromedan!!