The ‘Science’ of Kangaskhan

As everybody is aware, Kangaskhan poses many problems to Pokéscience. The number one thing that is of great concern is how Kangaskhan is born with a baby Kangaskhan already in her pouch. The second is how nobody knows whether baby Kangaskhan evolves into adult Kangaskhan. The third concern is how they are always female.

According to almost every Pokedex entry, anime episode and pretty much everyone in the world, Kangaskhan is baby Kangaskhan’s mother. It seems fairly well established, especially with the Parental Bond ability that mega Khan has. I have only one way to explain the anomaly of Kangaskhan hatching out with a baby already in her pouch and it relies on the theory that eggs are not eggs, but are actually ‘cacoons’ that house a baby Pokémon until it is ready to evolve. If this is the case, then the egg cradle actually holds twin Khans, but only one evolves upon ‘hatching’. Therefore the very first baby that Kangaskhan carries in her pouch is not actually her baby, but her sister. Since baby evolution is based on happiness and not experience, one could easily evolve before the other. After approximately three years or more when baby Kangaskhan is ready to leave the pouch because she is happy and well cared for, she evolves into an adult Kangaskhan and reaches sexual maturity. The original Kangaskhan can pop out another baby almost immediately because of her resemblance to the real life kangaroo. Kangaroos who are pregnant but also nursing can suspend the embryonic growth of the foetus until the older baby has been weaned. This process, called embryonic diapause, prevents the blastocyst (the very small embryo) from attaching to the wall of the uterus and developing. Mother Kangaskhan utilises the same method to give birth to a new baby as soon as the older one has left. Alternatively, she allows the development of the embryos, but bundles the babies up in a ‘egg’ if she is already keeping one in her pouch. Like many animals like Callitrichine monkeys of bears, Kangaskhan are very likely to have twins.

The second question, how nobody has seen a baby Khan evolves into an adult Khan, could be based on the protectiveness of the Mother while the baby evolves. But really, when it comes down to it we are taking the word of professors who can’t even tell whether we are a boy or a girl, so can we really rely on what they ‘see’ anyway?

An explanation of how she breeds without a ditto or male Kangaskhan is really quite simple. Pokémon breed within egg groups, which is essentially their genus or family, instead of breeding within species. Kangaskhan doesn’t need a male Kangaskhan to breed with but will suffice with anything in the monster egg group. It is much more difficult to explain how Tauros or Mr. Mine were bred before Ditto. However, all Kangaskhan are female, and this is of some concern.

In humans, sex is determined but the type of allosomes (a fancy word for sex chromosomes) one possesses. Females are determined by two X chromosomes and males are determined by an X and a Y chromosomes. The Y chromosome carries the gene SRY, which does some magical biochemistry to cause testis development. The X chromosome does not have the SRY gene so no male development occurs. Since this is the type of sex determination system everyone learns at school, it is easy to see why there is so much confusion about mono-gendered Pokemon. However, biology is never that simple.

I have two theories about why Kangaskhan are all female. The first is that the sex determination system of Khan is similar to that of the tuatara; namely, temperature sensitive sex determination. This system does not rely on the type of sex chromosomes one possess but rather the temperature at which the embryo was incubated. This occurs because enzymes function at different ideal temperatures, and since enzymes are the magic behind biochemistry, the enzymatic patterns determines the expression levels of the sex determining factors. This usually occurs in reptiles, but Kangaskhan is a mammal. However, Khan has some reptilian cousins (Tyranitar, Rampardos), which may mean they most likely both share a reptilian common ancestor for her to retain these genes from. However, now that they are mammals they retain a constant body temperature, and we all know that she keeps her embryos inside of her. If this is the form of sex determination that happens, all the embryos will be incubated at the same temperature and therefore be the same sex: female.

Alternatively, sex could be determined in the same manner as the disgusting little insect called the false spider mite. This mite has predominantly female eggs, but in a peculiar way. False spider mites determine sex in an XX XO system. Females are haploid, or have only one chromosome, and males are diploid, or have a chromosome pair like humans. The eggs of the mites are infested with a bacterium that somehow kills off sperm to prevent fertilization of the eggs, leaving only eggs that have one chromosome. This is likely due to the bacterium using the female egg as a host, which the males cannot produce. The bacterium preferentially kills off sperm so there are lots of females to lay eggs for them to live in. With haploid sex determination, no fertilization is needed to produce offspring. This also happens with bees, except that males are haploid and females are haploid. However, since there are so many female only Pokemon (Chansey, Mandibuzz, Jynx) and there are all from different eggs groups, it is easier to assume the latter theory than to former, because the former would suggest that were all closely related. Who knows, maybe it is a combination of the two?


The ‘Science’ of Pokemon Eggs

Pokemon come from eggs. For reptilian Pokemon such as dragons, Krokorok and Ekans, as well as fish or bird Pokemon, this isn’t really a big deal. However, the questions start to develop when we realise that some Pokemon are quite simply not reptiles, fish or birds. What about mammalian Pokemon like Tauros, or Meowth? Even more strangely, what about human-like pokemon such as Alakazam or Jynx? Beyond that, what about plant-like Pokemon and ‘objects’ such as geodude?

I can’t explain everything, but I can definitely pretend I know enough about Pokemon ‘science’ to give it a try.

Theory one – Monotremes


First of all, why do mammalian Pokemon lay eggs? This really was the most simple of the questions, because we know that mammals already do lay eggs. What, you say? Mammals don’t lay eggs! It is what DEFINES mammals! Well, because I live in Australia, these mammals are quite familiar to me. There are two crown groups that make up the Mammalian group; Therians consist of placental mammals such as cats and marsupials such as koalas, and Monotremes consist of egg laying mammals such as the echidna or platypus.

This could easily explain how mammalian Pokemon lay eggs (assuming they truly are mammals). What it doesn’t explain is why so many of them do lay eggs instead of giving birth to live young, like the mammals we know. My explanation is tenuous, but it is the only one I can offer.

There are two main methods of giving birth. The first is oviparity, or laying eggs, and the second is viviparity, or giving birth to live young. There are advantages and disadvantages to both, which could possibly explain why Pokemon only favour one.

Oviparous animals undergo embryonic development outside of the mother’s body. The formation of an egg requires relatively little energy expenditure from the mother, but leaves the egg much more susceptible to environmental stresses and possibly a lower survival rate. Oviparous mothers often lay more eggs to compensate.

Vivaparous animals undergo embryonic development within the womb of the mother. This requires large energy expenditure from the mother so they can only give birth to a smaller amount of babies. However, the survival rate of the babies is higher because there are not susceptible to the same environmental stresses as eggs. Some animals actually do both of these methods, by allowing the egg to hatch inside its body, but very few do this.

The crux of the matter here is which of these options is the most viable. For fish, it is much better to lay hundreds of eggs and leave them in an environment that is fairly stable. For mammals that produce copious amounts of energy and face huge environmental fluctuations, it is mostly better to give birth to live young, because they have the energy to do so. But what about in the Pokemon universe?

From the looks of things, humans have been using Pokemon to battle each other for centuries. It could be that egg-laying has been selected for due to this environmental factor. Enough energy is required to fight that it is better to conserve this energy instead of using it for reproductive purposes. This alone wouldn’t fix this trait, but it could potentially aid it.

In terms of competition, it doesn’t seem like Pokemon need to lay lots of eggs at once, but one will suffice. Maybe there is less threat to the egg than in our world. This could be a compromise between energy expenditure and survival, as this would have low energy and possibly high survival if other Pokemon don’t target eggs.

However, this theory still has many flaws, as I simply cannot believe the Pokemon ecosystem would allow for such a homogenous population and still survive. However, I have another theory that I am more inclined to believe.

Theory two – Eggs are not Eggs


My second theory resides less on science and more on the game and anime canon. In an unfortunate departure from the world I love so much, we may not be able to explain Pokemon biology with our own science (big surprise there).

My second theory is that Pokemon ‘eggs’ are not actually eggs in the way we know them, but are rather a colloquialism used. This could be through lack of knowledge or simply because it is easy to say. Instead, the ‘shell’ of the egg is more of a cacoon, in which the baby pokemon rests in a sort of suspended animation until it is ready to evolve into the Pokemon we encounter after hatching. This would mean the Pokemon inside the cacoon is a pre-evolution, or in an earlier life cycle, than the one that normally hatches out.

This theory is based on a few things said by in game characters. A certain Monsieur in Coumarine in the country of Kalos suggests that eggs are more like cradles that hold a Pokemon. He may not know a thing about Pokemon development, so we can’t rely on his word alone. However, the girl at the day care centre in Solaceon Town in Sinnoh mentions that nobody has actually seen a Pokemon lay an egg. This is consistent with all the other day care centres where you a told the Pokemon was found “holding an egg”. The day care people never know where it came from. This doesn’t prove that they are not eggs; it only shows that people in the Pokemon world can’t confirm that they are (which is a terrible argument without any more evidence).

In generation I, which happened at approximately the same time as generation III, ‘baby’ Pokemon such as Pichu hadn’t been seen in Kanto. Hoenn was a little more scientifically advanced and did know about a few baby Pokemon, but it still seems strange that a whole country could miss something like that if people were actually seeing what hatched from the egg. In generation III it is shown that some Pokemon can only breed baby Pokemon if they hold particular incense, which in some ways explains why Kanto were ignorant of them. However, I don’t think the incense is what makes the Pokemon ‘appear’, but I must explain something else first.

All baby Pokemon evolve with happiness and are unbreedable. Pokemon eggs do not hatch with time, in hours or days, but with steps. Pokemon happiness and friendship increases with steps also. In fact, the same game mechanics that dictate egg cycles is the same that dictates happiness. In the anime, eggs might follow this mechanism for hatching. Togepi hatches after every one finally stops fighting over the egg and after it has been cared for. Since it was an ancient egg it seem peculiar that it hadn’t hatched before. May’s Manaphy hatched after she caught it to prevent it from breaking. When eggs hatch they glow, in a similar manner to when Pokemon evolve. So my theory is this; there is a Pokemon inside the ‘cradle’ that is fully formed but dormant. Eggs hatched when they are happy enough, whether it is through the care of their mother of a human. Eggs that are extra happy will ‘hatch’ earlier than normal and this results in a baby Pokemon which cannot breed and must evolve into the next stage of their life through happiness. The incense that a parent holds promotes the premature hatching of an egg, and therefore a baby Pokemon. Kanto did not understand this mechanism, so eggs were not hatching prematurely into baby Pokemon. This theory would suggest that every Pokemon has a baby Pokemon that lies dormant in the egg, and once the egg is happy enough, evolves into the form we know as the lowest in the evolutionary chain. Most Pokemon hatch when they are sexually mature, but the Pokemon inside the egg isn’t, hence why baby Pokemon who have hatched pre-maturely can’t breed. So there is a pre-evolved baby larvitar that evolves into a sexually mature Larvitar at the same time as it breaks out from its ‘cradle’. Some Pokemon are more susceptible to premature hatching (e.g. riolu) and others are not, but it would explain why most Pokemon can breed the same day as it hatches.

Another reason I am more inclined to believe this theory is because Pokemon ‘eggs’ resemble the skin of the Pokemon inside. This may mean very little, but if there was only yolk and albumen inside, this would be an extremely poor way to ensure the safety of a growing embryo. A pidgey, even the dumbest pidgey, would have absolutely no problem locating a bright yellow elekid egg. However, if there is an actual Elekid inside it may deter the pidgey slightly as it doesn’t want to be shocked. Furthermore, eggs have been known to use moves before they hatch. In the episode Address Unown, the Manaphy egg uses the move Heart Swap. If it was an embryo it is difficult to believe it had any concept of what was going on outside, let alone actually be able to use a move. They also have base stats that are programed into the game. If it had just been laid and isn’t even an embryo yet, this seems strange.

Now, this would be an extreme departure from real world science, where I have not found a single instance of this sort of thing besides actual cacoons, which still only act as protection during metamorphosis. However, there are a bunch of pokemon that go into suspended animation, whether it be during the embryonic stage like with Kangaroos, or hibernation like bears, and lower the bodies energy levels to such a low amount that they become dormant. This helps plenty of animals live for a long time with no energy intake. Maybe this is why that Togepi egg lived for so long, or why some eggs hatch quickly and others slowly. It is not that a Pokemon is developing inside but that a Pokemon is ‘sleeping’ in it.

This offers no explanation as to how the babies are born, but it is possible that they are born in which ever way suits the Pokemon (live birth or eggs), wrapped up in a ‘cradle’ and discovered when the day care man comes to have a look. So maybe rock Pokemon physically build their babies out of rock before wrapping them up, or grass Pokemon spore. Who really knows, since nothing is actually confirmed?

This theory still comes with a lot of problems. This would mean nobody eats eggs, or that eggs that are eaten haven’t hatched and been wrapped up in a cradle. It is also a very tenuous link between happiness and egg hatching, and strange that nobody has seen it happen. However, it may just be possible. What do you think?

The Girl in Question

Well, Hello there.

It seems you were bored enough to stumble across me, so I suppose I should tell you a little about myself.

My name is Debbie. My last name is classified. Doobius Caesar is the name I use for all (two of) the games I play.

I am currently a PhD student in Adelaide, studying plant genetics, because honestly plant genetics is the most fascinating subject of all. I play far too much Pokemon, although I lose most battles, and if I lived in Kanto I would totally still study plant genetics.

The purpose of this blog is undecided. Mostly, I enjoy to write and procrastinate, so this gives me an excuse. I mostly talk about Science in the Pokemon world so that I can combine two of my loves. Who knows? Who even really cares? It’s up to you to choose whether it is interesting enough

Hello world!

This is your very first post. Click the Edit link to modify or delete it, or start a new post. If you like, use this post to tell readers why you started this blog and what you plan to do with it.

Happy blogging!

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