Yautja

The Yautja (E-wat-ya) - more commonly known as Predators - are a hunting race from the farthest reaches of the universe. The males of the species live for the thrill of the hunt. They also see it as a sport and a mission to earn their "Promise Marks." When speaking in Earth terms, Yautja are best classified as therapsids (sometimes called mammal-like reptiles), this means that they are reptilian creatures that are warm-blooded, which may hint at a synapsid-like evolution.

Yautja are adapted to hot climates, and can allegedly withstand temperatures up to 250°C (482°F). They also possess arthropodian (insect, arachnid, and crustacean) and amphibious features as well. Their mandibles are arthropodian and their skin seems to be scaly like a crocodilian's, but also soft and leathery like an amphibian, similar to a frog or salamander.

Biology
Yautja skin is primitive-reptilian, which means they do not possess scales like a Squamatan's (although some crocodile-like scales are found on the backs of their hands, arms, and back), but skin similar to early mammal-like reptiles on earth (Such as Lystrosaurus) Although, when faced with colder temperatures, the Yautja skin becomes rigid due to the scales sticking to one another. This makes movement uncomfortable and, in cold enough tempuratures, can even rupture the skin at the slightest movement, causing small lacerations that cannot heal untill they reach a more normalized temperature. It also gives good protection against small caliber weapons (i.e. 9mm rounds) like a bullet proof vest. Yautja are warm-blooded.

According to the Aliens vs. Predator novels, the average height of males is two and a half meters (eight feet and two inches). As with humans, height varies among different individuals. Top Knot, an imposing Yautja leader, is a head taller than his rival Broken Tusk, a Yautja of average size. Only 2.0m-tall, the character Shorty is diminutive compared to his fellow Yautja.

The skin color has many variations, ranging from brown-reddish colors right through to bluish-greenish colors. The large variety of colors and patterns likely came about when the Yautja began to settle on other planets. Presumably, their ships were not as fast then as they are now, and it would have taken some time just to get to another star system. Yautja on other planets would have been almost cut off from the rest of their species. These Yautja would then start to adapt to this new environment, producing a great variety of colors and patterns.

The Circulatory System
The Yautja circulatory system can be divided into 3 distinct; probably closed, circuits: In the Yautja circulatory system, the brain has a separate circulation. This allows for a higher blood pressure in the rest of the body without damaging the fine network of blood vessels in the brain. This allows the Yautja to live with blood pressures that would normally kill a human.
 * 1. From the heart to the lungs.
 * 2. From the heart to the body.
 * 3. From the heart to the brain.

The ability to maintain such high blood pressure has certain advantages. The blood can be transported through the body faster, and thus, oxygen and other nutrients are transported quicker and waste products are removed faster. This is part of why the Yautja are so strong. It allows the organs and muscles to work harder and thus increases  muscle capacity.

The Yautja's five-part heart consists of two auricles and three ventricles. The blood is pumped from the right side of the heart (seen on the left of the heart schematic in blue) through the lungs. From there, it goes back to the heart and into the left auricle (seen on the right of the heart schematic in green). From here, it goes into the two ventricles that are connected to it. One pumps it into the body, and the other pumps it into the brain at a much lower pressure. When the blood has gone through the body and the brain, it goes back to the right side of the heart and the cycle starts again.

Skeleton
The Yautja skeleton is stronger than our own, although it is made mostly of Calcium, which our bones are constructed of as well. The Yautja skeleton is stronger due to its firm build. The bones are much denser than our own, and are heavier.

Partially due to the oxygen rich blood, the Yautja don't seem to have the problem of calcification, a process that makes bones more fragile over time. This also allows the bones to reinforce their structure naturally and also because their body uses more carbon in making the bone, which makes it just as flexible as, and stronger than, human bone tissue, but about 3-4 times more dense and 5-6 times more heavy.

Muscles
The reason Yautja are much stronger is due partially to the fact that the muscles have a much more efficient nutrient and waste product transport, as well as the much higher gravity on their home planet, and that the muscle fibers are prismoidal and triangular, as opposed to a human's round muscle fibers. This allows more muscle to fit in the same amount of space, and due to the larger size, attributes to the greater strength.

The greater strength is also created by the higher percentage of muscular tissue per KG of body weight and the fact that Yautja are typically larger than humans.

Nervous System
The Yautja' nervous system is almost a replica of human nerves other than DNA and a few structural changes. The nerves use a form of organic fiber optics that allow chemical and electrical signals to travel at speeds up to 20 times faster than a human's. Also, instead of remaining relatively close enough for signals to take place, the nerve endings grow past each other and intertwine, allowing for much faster communication.

DNA
An interesting thing about the Yautja is their unique DNA structure. Instead of a double helix, the Yautja have a triple helix DNA form. The advantages and disadvantages of this are unknown. Also, instead of 4 base pairs like humans, they have 5 base pairs in their DNA. These differences may also have unknown advantages or disadvantages.

Head "Dreadlocks"
A recent theory suggests that the tubular "dreadlock" tendrils located on their heads (resembling the Human hair style) are not actually hair, but actually a unique cooling system utilizing hollow tendrils lined with blood vessels to help dissapate heat. Since Yautja do not sweat, this allows the heat generated by the Yautja high metabolism to be released easily. The air inside the tendrils also acts as an insulator to resist absorption of heat from the outside environment, enabling them to resist high temperatures relatively well. It is also useful in cold climates, in which the air in the tendrils is heated by the body, and retains this heat, keeping them from losing too much heat from their tendrils. This is further supported by examination of the head and skull, showing the tendrils being socketed directly into the skull.

Breathing
The Yautja breathe 35% more oxygen than humans due to their larger muscle and metabolic requirements. Due to adverse climates and terrains on their home world, they evolved the ability to breathe hydrogen and a limited amount of carbon dioxide if there is a lack of oxygen in the air. But, like humans, they are limited to how long they can go before their bodies can no longer function without oxygen. They are limited 10 minutes without breathing in carbon dioxide. This allows them to survive in adverse climates on many worlds with limited supplies. Also, due to a larger lung capacity, as an average, Yautja can hold their breath for up to 15 minutes before losing consciousness, whereas a human would be unconscious in only two (although with training a human free-diver can last much longer). Thus, an approximate maximum amount of time before a Yautja would need to breathe again would be just under 45 minutes.

Blood
Yautja blood is a luminous phosphor-green colour. Yautja blood is also a base, and thus is a bit more resistant to the Xenomorph's acidic blood than that of Humans.

Reproduction
Unlike humans, who reproduce the whole year round, the Yautja seem to have a mating season. This makes sense since they have a cycle in their life.

Interestingly, the Yautja mating season does not seem to be written in stone, as both males and females are capable of reproducing outside the mating season (similar to humans, although humanity's 'mating season' is simply the females' ovulation cycle). Normally, creatures who have a mating season can only reproduce during the mating season. However, it seems that Yautja can reproduce the whole year round but won't.

There are 2 theories as to why this behavior exists:
 * 1. Mating season is part of their culture and is sustained for religious reasons or for the sake of tradition.
 * 2. Mating season is simply convenient because of the earlier mentioned distances between males and females.

Mating season is a 30 day period which occurs roughly every 400 days. During the mating season, the males try to mate with as many females as they can. The high ranking males will attract enough females, simply because of their status. The males that are lower in rank, however, will usually have to fight for their females. This behavior is likely millions of years old. It is likely that the flat crests on top of a Yautja's head were developed for the sole purpose of attracting a mate. During mating season, a successful male can mate with up to 20 females. This only happens to very successful males who are excellent hunters. For the overall population, 2 or 3 females are plenty. But because of this type of distribution of females, many males are left without mates. This is also the reason most males don't mate for the first time until they are at least 50 to 60 years old and have acquired a reasonable trophy collection. Sometimes it doesn't happen at all, for instance when a male is seen as unfit for breeding, or when the Yautja becomes dishonorable or cowardly. Sometimes, the lowest hunting males are also unable to acquire a female. These frustrated males may turn on their subordinates.

The Yautja male reproduction system is similar to that of a human male. Conversely, the female reproduction system differs quite a lot from that of human females. The outside appearance of the female reproductive organs is similar to that of a human, but the inner workings are quite different. Although Yautja give birth to live young, the babies develop in an egg like structure. This is called ovoviviparous reproduction. A similar type of reproduction implied by some snakes, having non- or soft-shelled eggs which hatch inside of the female.

In Yautja, this type of reproduction has evolved itself into something much more specialized than just the hatching of an egg inside the body.

In the ovary, only one egg at a time ripens. It takes 40 days and the egg will be ready to be fertilized for the next 70 days. Although the egg is ripe and ready to be fertilized, it is not yet fully grown. It will only grow to its full size when it its fertilized. The egg is fertilized whilst still in the ovary, which will allow it to develop further. When the egg is fertilized, the yolk, which will have to support the growing Yautja fetus, starts to grow in mass. The next 80 days will be crucial. In this period of time, the yolk grows to its full size and the fertilized egg starts to develop into a fetus. Meanwhile, the walls of the "womb" start to produce a thick coating of moist holding slime and blood vessels. This coating will later on provide the growing fetus with oxygen, fluids, and a means of removing the carbon dioxide and other waste products. Before this time, the egg gets it's oxygen and water from the albumen. After the first 80 days, the egg has grown to its full size and detaches itself from the ovary. The womb coating will cover it completely within days. The fertilized egg has now become an embryo and the basic shape of the Yautja has revealed itself. The embryo is attached to the yolk by an umbilical cord, it will get its food from here for the next months. From now on, the embryo will keep growing until it has become a baby ready to be born.

Nearing birth, the yolk shrinks to the size of a Ping-Pong ball, although it isn't round. In the next few hours, the yolk will merge with the embryo's abdomen. When the child is born, the yolk can still be seen as a small elongated bump on the stomach with a slightly different color as the rest of the body.

This type of reproduction has definite advantages over actually laying eggs. The eggs can grow much larger because they don't need a hard shell. The yolk can grow much larger because the amount of albumen needed is reduced immensely. The womb coating provides the oxygen and water that used to be provided by the albumen.

Society
See Yautja (language) for the species' language!

The Yautja society is made up of different classifications, including blooded and un-blooded. Their caste includes:


 * Unblooded - About 25% of male Yautja are unblooded. This means that the Yautja have no distinguishable kills amongst their race, such as killing a Xenomorph. Once a Yautja kills a Xenomorph and collects its head as trophy, they become blooded. All unblooded are children too young to safely hunt for Xenomorphs, or they simply have not had the chance to battle a Xenomorph yet.
 * Blooded - About 45% of male Yautja are blooded. These are warriors who have gained the clan symbol upon their forehead after their first successful Xenomorph hunt.
 * Retirees - About 10% of male Yautja are retirees, Yautja who have fought their time and now are too old and honoured to hunt. Females commonly come under this section due to their roles as mothers and the driving force behind the homeworlds natural wasteland systems.
 * Elite Predator - Elite Predators are often leaders in their clan, and are only elevated to the caste of Elite Predator once they have acquired a Queen Xenomorph skull.  In some cases, more skilled clans who are made completely out of Elites can compete in battle against Xenomorphs to earn the title. Also the Yautja must also be born into that clan to do so. About 15% of blooded Yautja are Elite Predators. Once an Elite Predator they specialize in certain a weapon making it their strongsuit.  A Brawler specializes in Wirstblades, Spearmaster specializes with the Combistick.  Elite Predators often become retirees after a few decades.
 * Clan Leader - Clan Leaders are only made by the Adjudicator's decision. The only way to become a Clan Leader is to clean out an entire Xenomorph hive which is larger than 300 members in population with a maximum of two others. When this has been proven, the three (or fewer) Yautja all become Clan Leaders. They become the forefathers of that clan and will repopulate with females of their choosing.  In order to be eligible for the trials of a hive cleansing, each member of the trio must have at least 3 Queen skull trophies. After this point, any hive cleansings that the forefathers complete will give the clan greater honor and standing in the caste system. Clan leaders comprise 5% of the Yautja society.
 * Adjudicators - The adjudicators are the administrators and law enforcers of the Yautja. They are world leaders and the ruling fist in the overall scheme of the Yautja culture. Less than 1% of Yautja are adjudicators, due to their massive role in the world.  At this point, they simply no longer have time to hunt off planet anymore, but often foray into the underground contained hunting grounds, where younger hunters train in order to lend experience to the young ones.  Adjudicators are always the leaders of a clan and no adjudicators have ever risen to that position without first having completed at least five hive cleansings.
 * Bad Bloods - These are the criminal Yautja whom have been sentenced to death and escaped. Their justice system shows that crime is very low. About 2% of Yautja are bad bloods. In Predator: Concrete Jungle on the Playstation 2, bad bloods were also Predators captured by humans and brainwashed. They met honorable deaths by their clan brother, the main Predator in the game.
 * Apprentice- These are honorable humans taken by Yautja to learn their ways.
 * Known Predators- Predators in the movies include the original Predator from the movie who is given the name Jungle Hunter. City Hunter is the name given to the main Predator in Predator 2. Predators from the AVP movies include: Celtic, Chopper, Scar, and Wolf. In the movie Predators, there are three "Super Predators" that include: Tracker (or Flusher), Falconer, and Berserker (or Mr. Black) along with a regular Predator given the simple name: Classic Predator (also referred to as Crucified Predator). In Predator 2 the whole Lost Clan is shown which includes the Clan Leader (Greyback or Golden Angel), Boar, Lost, Stalker, Gort (Guardian), Shaman, and multiple others. From the Aliens vs. Predator 2010 video game there are the following Predators: Dark, Claw, Stalker, Wolf, Spartan, Lord, and the Alien Predator which is a Predator that wears an Alien's (Xenomorph) face as a mask. In the movie Aliens vs. Predator there is a clan leader and other various Predators. From the video game Predator: Concrete Jungle the main charcter Predator is nick-named Scarface. There are three other Bad-Bloods named Swift Knife, Stone Heart, and Long Spear. There is also another clan leader and other numerous Dark Blade clan members. Throughout the comics there are many other Predators which are not given names and some are such as: Scavage, Spike-Tail, and Cracked Tusk.
 * Champion - These are predators who have recieved great honour and respect among others including clan leaders. To achieve this status a predator must cleanse a hive with a population of over 300 xenomorphs and kill a predalien all on his own. Dark, the main protagonist of the Predator campaign from the third AVP game, achieved this after killing "The abomination" and escaping the planet.

The Hunt
Male Yautja hunt and from this comes the appellation of "Predator." Before his first hunt, he is an unblooded Predator. When an unblooded Predator completes a hunt, he is marked and is now a Blooded Predator. A Predator has better hunting gear the higher rank he is. When the Predator proves himself worthy enough, the elder will present the Predator the Combi Stick, which is rare in their culture. Other rare items include stronger Plasmacasters, the laser-guided Smart Disc, and Razor Whip. Male Yautja hunt on Earth every 100 years. When they kill their first Xenomorph, they use its acidic blood to form a mark on their helmet and on the head. If a Predator is to fall in battle during a hunt, a more experienced Predator is sent to activate the now deceased Yautja's wrist bracer to overload, causing it to explode in a manner that erases all trace of it ever being there.

Technology
See: Yautja technology

In the game Alien vs. Predator: Extinction, the spear master's armor is made out of a Vy'drach, which lives on the infernal deserts of Yautja Prime, surviving heat and radiation strong enough to bake most life forms. All Elite Predators wishing to be a Spear Master must kill a Vy'drach. Its hide is then made into armour that absorbs heat, plasma, and acid to a degree.