Human

Humans are a weak species in combat standards that appear in the Metroid series. They don't seem to be any different from real-life humans except for their advanced technology, such as cybernetic enhancements. As they did not evolve to grow body parts that can be used as a harmful weapon, making them physically weak, but they are mentally superior too other species, being able to make powerful weapons to make up for their weak strength. They play a large role in the Galactic Federation and helped create it as referenced in the Metroid manual. Samus Aran is a human and possibly the most powerful human in terms of battle capacity. Some Androids have been created that resemble humans, such as MB.

As prey
Humans have been known to be included Ridley's diet. While it may not be only humans, Ridley is able to consume their flesh in order to regenerate his own. It's not mentioned if he prepares them in any way.

The X and Metroids are also known to prey upon humans.

Known Humans in the Metroid Series

 * Chief Rodney Aran
 * Samus Aran
 * Virginia Aran
 * Madeline Bergman
 * Bomad
 * The Colonel
 * Damara
 * Fleet Admiral Castor Dane
 * Captain Dare
 * Ensign
 * Maurice Favreau
 * Federation Marines
 * Chief Hardy
 * Head Quarantine Officer
 * Anthony Higgs
 * Armstrong Houston
 * Male Fleet Troopers
 * Female Fleet Troopers
 * Fleet Mechanics
 * Incoming Dispatch
 * Joey
 * Michael Kelbaugh
 * Commander Adam Malkovich
 * Ian Malkovich
 * K.G. Misawa
 * Commander Nemo
 * Scott Petersen
 * James Pierce
 * Ryan Powell
 * Luis Ramirez
 * Lyle Smithsonian
 * Quarantine Officer
 * UMS 7
 * Chet

Enemies

 * Dark Samus
 * Dark Trooper
 * Dark Missile Trooper
 * The Deleter (James Pierce)
 * Zombie researcher

Trivia

 * While humans are a species of mammals, a handful of species in the Metroid series appear mammalian. Others include Etecoons, the IceBoss, and Rabbilis.