What physical characteristics would make aliens seem less alien to humans?

Aliens that seem less alien to humans would likely share several physical characteristics with us. Here are some features that might contribute to a more familiar appearance:

1. Bipedal Form: Walking on two legs, similar to humans, would make them seem more familiar. This includes having a generally upright posture.
2. Symmetry: Bilateral symmetry, where the left and right sides of the body mirror each other, is a common characteristic in many Earth organisms, including humans. Aliens with this feature would appear less foreign.
3. Facial Features: A head with two forward-facing eyes, a central nose, and a mouth beneath the nose would make an alien look more human-like. The presence of facial expressions similar to human emotions would also help.
4. Limbs: Having two arms with hands (each with fingers) and two legs with feet would make them more relatable. The ability to grasp objects with hands similar to ours would enhance the familiarity.
5. Skin Texture and Color: While variations in skin color are normal among humans, an alien with skin that is not too far removed from human tones (ranging from pale to dark) or with a familiar texture (smooth or slightly hairy) would seem less alien. Extreme differences, like scales, fur, or a completely metallic surface, would be more alien.
6. Size and Proportions: Aliens that are within a similar size range to humans, neither too small nor too large, would be less intimidating and more relatable. Proportions similar to human anatomy (e.g., head-to-body ratio) would also contribute to a sense of familiarity.
7. Speech and Communication: Aliens that communicate using sound, particularly if their language includes sounds within the human vocal range, would seem less alien. Even more so if they use body language and facial expressions to convey emotions.
8. Social Behaviors: Exhibiting social behaviors akin to those of humans, such as forming groups, showing empathy, and cooperating, would make aliens seem more relatable.

These characteristics, which align closely with the human form and behavior, would help reduce the perception of alienness.

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