The Heartlands Ikran is an aerial predator that the Na'vi have learned to bond with.
This type of ikran is found throughout the skies of the Heart of the Plains.
Anatomy[]
Leathery membranous wings stretched taut over hollow bone structure. Large distensible jaw. Complex coloring scheme. Teeth are obsidian-like and extremely sharp. Bones composed of biologically produced carbon-fiber composite.
Shape of jaw indicates that ikran may have evolved from fish. Wingspan of up to twelve meters.
Can make subtle adjustments to flight attitude and speed with an articulated tail tip, which can flare or remain tucked.
Na'vi culture[]
Bonding with an ikran is a dangerous and required rite of passage for all would-be Na'vi warriors. Like the direhorse, a Na'vi can connect to an ikran through a neural interface that allows animal and rider to move with apparent effortlessness through the skies. Unlike the direhorse, however, the ikran will only bond with one Na'vi in its lifetime.
Description[]
The mountain ikran (like its smaller cousin, the forest ikran) is highly adapted for flight. Specially developed muscles attached to the breastbone allow for the powerful strokes needed to achieve lift.
Xenobiologists continue to study the aerodynamics of the ikran. It is believed that all of Pandora's flying animals take advantage of gravity that is lower than Earth's and the increased air density, (which requires more force to displace with the downward/rearward stroke of their wings, and thus gives the animal's body more impetus with each flap). The downside is that the denser air is harder to move through, and requires highly-efficient streamlining to achieve high flight speeds.
Though reptilian in appearance, the ikran has a metabolism that is bird-like, and generates tremendous heat. The ikran has a complex cooling system to keep it from overheating during strenuous flying. The breathing system is central to this cooling. The air inlets, or spiracles, face forward at the front of the chest cavity, like the engine intakes of a jet fighter. Induction of air is controlled by a cartilaginous operculum, or flap-valve. The ikran lung is a bellows like structure, inflated by rib movement, but unlike the lungs of terrestrial animals, it has unidirectional flow, venting aft through gill-like slits.
Like many of Pandora's creatures, the ikran also has a remarkably strong cell structure. This structure, which is a biologically produced carbon-fiber, makes their bones much lighter and stronger than any organic Terran equivalent. This in turn allows them to generate more power and lift with every flap. The biochemistry of their muscle tissue allows them to generate nearly twice the force per pound of muscle as terrestrial flying animals such as bats and birds. This, again, generates tremendous metabolic heat. The hollow bones are connected to the bellows-like lung, and cooling air moves through the long bones of the fore and aft wings.
Each large fore-wing has three Primary Vanes at its tips. These form like the wings of a dragonfly, by the extrusion of a resin into the veins of a flexible membrane, which unfurls then cures in the sun into a rigid transparent vane. These vanes are replaced through molting. The purpose of the vanes is to generate lift and to provide fine control in flight. They are also quite robust structures designed to fold inward if the wingtips hit tree limbs or other obstacles.
The smaller hind wing, or canard, plays a dual role in ikran flight. In level flight, when large amounts of power are not required, the creature propels itself with the fore-wing and uses the canard as a tail-plane, for steering. When more power is needed, for take-off and climbing, or escape from an aerial predator such as the leonopteryx, the canard becomes an additional wing, flappingto provide propulsion.
The steering vane under the ikran's lower jaw and the featherlike fan at the tip of the tail provide additional turning authority for high performance aerobatics. The ikran is highly maneuverable and can dive at speeds close to 140 knots. The ikran has two primary eyes which see in full color in roughly the same spectrum as human vision. Aft of the primary eyes are smaller secondary eyes, which can move independently or together with the primaries. They see in near infrared, for night hunting. They also are highly sensitive to motion, and act as an early warning system against attack from the rear. All four eyes are protected by lids and by transparent nictating membranes. Forward of the primary eyes are lines of sensor pits. These are thought to provide airflow information in flight, like a pitot tube on an airplane. Another hypothesis is that they are sensitive to sound, and have an echolocation role, by sensing the reflected sound of the ikran shrieks.
Ikran are known to humans as banshees, and were so named because of their piercing signature cry. This is only one of the ikran's many vocalizations, and is thought to be a distant call definingterritory. Other vocalizations include a warning hiss, which is part of an overall threat display posture, and a short sharp shriek which denotes stress or fear. There are also warning sounds, and other stress vocalizations, as well as more guttural vocalizations associated with social grooming and contentment. The ikrans are social animals, and communicate frequently, generating quite a din at rookeries and other communal areas. The ikran emits sound from its head, usingthe open mouth to focus the direction. However, it does not have a trachea in its neck, since it breathes directly into the chest cavity. It has instead, a tube running from the lungs up into the head which pumps air through the vocal organ, the syrinx. Chambers in the head amplify the sound before it is emitted into the mouth cavity for directional aiming. Some ikran vocalizations are emitted directly from the resonating cavity, when the mouth is closed.