Blue

The Blue are an aquatic race of Humans that lived beneath the seas of Earth.

Biology
Externally the Blue are indistinguishable from normal baseline Humans, however their internal biology is radically different. Their basic biology is slightly different than other Humans in that they have some additional brain tissue, their red-cell density is twice the average, have more flexible bone structure of someone still growing, and naturally have 5 times the lung capacity of an Olympic swimmer. All Blue can manipulate water.

There is also a breed called the Blue Elites, which are the specialist of the Blue, warriors capable of changing their physical bodies into water, letting it disperse and being able to pull themselves back together. Blue Elites have the potential for massive amounts healing abilities (even fatal ones), shooting blasts of energy from their hands and becoming energy.

Humans and Blue are capable of sexual recreation, though it's unknown if they are capable of interbreeding.

Culture and society
The Blue possess a mix of advanced technology and melee weaponry deemed archaic by Humans. The Blue have organically created ships capable of incredible speeds in, on and out of water. In addition they also have space-capable vessels, energy weapons (guns, wrist-mounted lasers and laser swords). The Blue don't have a united government, but instead separate themselves in massive underwater city-states.

Due to their aquatic environment and need for rapid locomotion in the water, they don't wear much clothes but they are usually seen in some kind of armor that resembles bone or coral. They were mostly an isolationist people, rarely leaving the water, but after underwater testing by Humans, the Blue have turned to more warlike practices for revenge against the Humans.

History
The Blue have long existed before the rise of humanity, living isolated beneath the seas of Earth. They are actually descendants of another race of Humans called the Black, which dwell in the far depths of the seas.

The existence of the Blue was discovered by a xenophobic American Admiral Maylander.

After the good admiral launched several unauthorized attacks on Blue cities, killing thousands of civilians, the Blue Councils demanded to be recognized and offered a full apology and reparations to the United Nations.

Peaceful negotiations ended when Mayweather sabotaged the peace summit and also the black appeared to announce their presence to both the Blue and the Humans. Relations between the two races further worsen when Chris Calloway, protégé of Maylander, murdered the Blue Ambassador, setting off a chain of events that backlashed the Blue and even Humans against the American government.

After a ceasefire was called between the United Nations and the Blue civilizations, both parties attempted to forge peaceful relations. However, their efforts were mostly hindered by Maylander, who went rogue and started his own private war on the Blue, and Blue terrorists obsessed with revenge. In addition many Human nations attempted to exploit Blue technology and genetics for their benefit.

Maylander then began kidnapping several Blue civilians for experiments, and later blackmailed several Blue to work under him to attack their own kind. When the Blue authorities learned of this they attacked Maylander's facility starting another conflict between humanity and the seas.

In any effect, Blue coexistence with humanity seems to be unlikely if not impossible due to the younger race's self-obsession with self-destruction.