Avecris are roughly human-sized, anthropomorphic creatures heavily resembling birds. They are shorter and smaller than humans, ranging from 4' 2" (1.4m) to 5' 6" (1.6m) at adulthood. Most of their body is covered in feathers, including wings and tail-feathers, and have a rough leathery skin on their hands and legs. They have wide beaks made of a hard cartilage-like material, used for eating and communicating.
Their beak, wing, and legs can vary between species, but all retain the same humanoid shape. In general, females are shorter, have longer tail feathers, and are wider at the hip than males, while males have broader shoulders, and shorter tail-feathers.
Avecris heads protrude from their torso, connected by a neck. Their faces are often round or square in shape, while their whole heads are more pointed. They have large beaks, taking up the lower portion of their face. These beaks are made of a cartilage-like material, and are flexible yet very firm, capable of producing aided speech. They have two large eyes, to each side of their face. Their eyes generally have sharp eyesight, with a particularly wide field of view.
Their whole face is covered in feathers, save for organs and beaks. They have small concave dips on both sides of their head, where an ear canal is located. These canals are protected by a small plume of feathers, that can flex and move with emotion.
Like most Arcadians, Avecris have very complex brain structures, more so than humans. They are capable of great feats, having full control over their bodies, as well as telekinetic control over their environment. Avecris can have similar abilities to all other Arcadians, including the bending of ethereal energy, the ability to open unstable rifts, and telekinesis. However, the brain is a precious and fragile organ, and can cause many negative heath effects should damage occur.
Avecris torsos are rather human-like in shape, but are thinner. They are covered in feathers, particularly downy ones down the chest and underarms. Avecris have tail feathers, that range in shape and size depending on species. Male Avecris are broader at the shoulder, and on average have short tail feathers, while female Avecris are broader at the hip and have longer tail feathers. The feathers covering their bodies produce a natural oil, helping to block out water, as well as get rid of excessive body heat. Unlike humans, female Avecris do not have mammary glands.
Avecris have a different bone structure than humans, overall significantly more lightweight than humans, while still preserving good strength. They have additional internal organs, including lungs with integrated air sacs.
Avecris wings can vary greatly in size and color, and are internally supported by a flexible cartilage. Wether an Avecris can fly or not depends on their wing size, mass, and health habits. The flexibility of these wings allow for easy folding behind the back and around the waist.
Avecris have bony arms covered in a leathery muscular skin, thicker towards the shoulder. These arms are mostly covered in muscle and feathers, save for their hands. Their hands are composed of four digits: three bony fingers, and one opposable thumb. There are talons on the end of each digit, and the hand is covered in a leathery skin.
The upper half of Avecris legs (thighs) are thick, covered in muscle and feathers. The lower half, starting from the knee, are bony, covered with tough skin akin to their hands. They are digitigrade, meaning they stand on their toes. Each foot splits into four large "toes" below the heel, with sharp talons on each end. Avecris can make themselves appear taller by standing higher on their toes. Due to the digitigrade nature of their feet, Avecris are naturally strong runners, evolved from having to run to take off.
Avecris reproduce sexually, and lay their embryo in eggs opposed to live birth. Eggs are most often laid in pairs, but triplets and more are possible. They do not have human reproductive organs, instead having a cloaca under their tail feathers.
Eggs are relatively newborn sized, and only begin development when fertilized. They are laid in under a few months of fertilization, and the Avecris embryo is developed within the in the next few months. Eggs will hatch naturally after a few months of development, and the new hatching's gender and features are based both on genetics and the environment they were developed in. The total time between conception and hatching is roughly seven months.
- Aves are heavily inspired by Avians, a playable race from the indie game Starbound.
- Avecris Anthropallis refers to both the words Aves and Anthropoidea.
- These both correspond to their birdlike appearance and humanoid stature.