R-type Final - Great yorkmingo

This huge monster can be encountered in the game R-type Final (PS2), at stages 2.1 and 2.2. I'm thinking about creating an animal documentary about it. But referring to my natural slowness, I think my project won't arrive before a loooong time...
 
I have to admit that I took a few liberties to depict the creature itself, especially the head. I'm aware about the fact that the first eye line is actually supposed to be more forward (above the middle theeth), but I've felt better to put it just behind the mouth. I've also exagerated the facial expression of the Yorkmingo, though I think that would be somewhat appropriate regarding its behaviour toward the human kind...

I'm not entirely sure about the scale. I used a video on Youtube and theR-type fighter displayed on it to estimate the size of the Yorkmingo. Though the R-type wikia website states that the R-9A Arrowhead is 16.2 m long in the original gameboy games, I think the new versions of the spacecraft are slightly smaller (about 10m).

Anyway, here is a first presentation of the creature characteristics. Of course, I have invented most of the following description, but I hope you will enjoy it
NB: English is NOT my mother tongue, thus there is strong probability that part of the following text is grammatically non-sense. If so, please refer to me so that I correct them. Thank you in advance!

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Common Name: Great Yorkmingo
Family: Apterygidae
Type species: Apteryx Bydo
Scientific Name: Apteryx Bydo Ingentis

Height: 36 to 42m
Length: 30 to 35m
Weigh: Unknown, but estimated to several hundred tons


Distribution: Mostly tropical and equatorial forests on low-gravity planets. Some specimens have been observed wandering in more temperate climates, several hundred kilometers away from their original birthplace.
Life expectancy: About one hundred years
Reproduction: Oviparous

Diet: Omnivorous: 65% herbivorous; 35% carnivorous (average mass percentage for an adult).
 => Herbivorous: large trees and river algae
 => Carnivorous: elephant-sized and larger preys; corpses and carcasses.


Background:
  
    As its name implies, the Great Yorkmingo is currently the largest known sub-species among "Apteryx Bydo". The species itself has been spotted by human pilots in one of the numerous colonies infested by Bydo life-forms. Early referred as "Yorkmingo" in reference to the African Flamingo by the military authorities in charge of the purge, it seems that animal is actually much closer to the Kiwi of New-Zealand. According to records found in the colony ruins, numerous earth animal species were brought to the planet in order to create and establish its future biosphere. Due to their good resilience and adaptibility, a group of North-Island brown kiwis (Apteryx Mantelli) was part of the animal transfer to the colony.
Recent studies have confirmed the phylogenetic kinship between yorkmingos and kiwis. The Bydo entity is infamously known to infect most life-forms on its wave path and tremedously accelerate frequency of mutation within infected organisms. Scholars assume that current Yorkmingos are descended from several brown kiwi acclimatized within the colony and subconsciously submitted to the mutating Bydo wave. However, other Bydo life-forms of the colony have developped physical parts surprisingly similar to the yorkmingo head, while having no well-established phylogenetic relationships with the kiwi gender. In fact, it appears that the Bydo wave had "selected" several genes on which massive changes occured: descendents of the infested animals developped similar physical parts on their bodies, leading to some of the most terrifying creatures that still infest the colony, including the Yorkmingo. Nonetheless, that theory still requires further researches to be fully approved.

Like any Bydo-infected organisms, Yorkmingos show extreme aggressivity toward any non-Bydo living beings, and are undoubtedly responsible of the destruction of the human colony. Though they had been mostly exterminated with other local Bydo creatures by R-craft pilots, the decision to eradicate the entire infestation was suddenly changed. Due to the high cost to rebuild the colony and the fact that the primary source of the Bydo wave had already been annihilated, military authorities aggreed to let the planet as a "extra-terrestrial reserve" under the responsability of a small organization mainly composed of biologists. Most of them were eager to observe how the Bydo wave affected these organisms to have a better understanding of Charles Darwin's Theory of evolution.

Metabolism:

Though all yorkmingo sub-species are endothermal animals, they have established a mutualistic relationship with two species of microscopic protists, which seem to play a important role in the internal thermal regulation of the body of the creature. The phylogenetic facets of these protists are not well-established yet. The military authorities initially referred them as "parasites" due to their harmful ability to infect the human body. However, they reveal vital to the yorkmingo's survival in harsh environments.
The density of those protozoan in the yorkmingo body is tremedous, even to the biologist's eyes. The first species is mainly located under the skin, while the other is located into muscles and flesh parts, close to internal organs. Both of them have access to blood vessels. They are believed to take refuge into the yorkmingo's body in order to find the nutrients they need for their own metabolism, which enforces the yorkmingo to spend most of its time to feed itself. Experiments conducted in laboratory reveal that those protists are very sensitive and responsive to relatively small changes in temperature: they have been observed to immediately generate endothermic or exothermic chemical reactions depending on if the temperature increases or decreases. These results have proved their implication in the thermal regulation of the yorkmingo's body, and may explain why some of those giants are able to migrate in harsher environments.
In addition to their thermal regulation role, both the protists have the ability to secrete hormones and molecules to "repair" surrounding damaged tissues. A fantastic performance which may provide the reason of the sucessful resilience and survival of yorkmingos, even after the purge perpetrated by R-craft pilots.

Behaviour:

The great yorkmingo is among the most ravenous creatures ever known. It is also among the few Bydo sub-species whose diet is not exclusively carnivorous. Actually it would have been difficult for this massive creature to survive with a menu that would mainly consist of much smaller preys. Scholars assume that some ancestors of current yorkmingos were much smaller at that time, and developed by chance the ability to digest vegetals. Those specimens progressively became bigger and bigger since they were able to sate their appetite at any time, while the exclusively-carnivorous yorkmingos forebears evolved apart from the "vegetarian" branch, and remain relatively small compared to great yorkmingos.
Like prehistorical sauropods, great yorkmingos cannot afford to loose time by chewing vegetals. They quickly eat large amounts of leaves and trunks that are grinded in their huge gizzard. Like most archosaurs, they also swallow stones to help crushing ingered food before it is digested.
Despite their partially vegetarian diet, great yorkmingos remain ferocious predators, which hunt any rationally sized preys they can snatch in their gigantic and powerful jaws. Some of them have been observed fighting underground "eves" coming to the surface. They also track corpses down from very large distances with their accurate sense of smell.


Great yorkmingos are neither very social nor entirely solitary. Unlike other yorkmingo sub-species, they generally tolerate the presence of their fellow creatures, and even warn them whenever they find a large prey or a corpse, like current ravens. However, they display much more aggressivity during mating season.
When a female is ready to mate, she shouts through the wide forest to attract two males. If one male arrived before another, the female will not let him approach until a rival has come. When the two contestants are finally there, they begin to fight to death. They generally use the toughened part of their head to make the other fall. But whenever one succeds, victory is not acquired yet: the fallen yorkmingo can use its long legs to strike his opponent and make him fall as well, or use the huge spikes located on its back to hurt him. After the end of the battle, the winner and the female cannibalize the corpse of the loser before they mate.
The female raises her offspring alone, which always consists in one single new-born. Young yorkmingos remain with their mother for at least 8 years, until they witness a fight between two other yorkmingo males and are able to wander in the dangerous homeworld by themselves.


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Irem Engineering Software owns R-type final and the corresponding creatures.