(2 Hours Later)

"Now let us get started with the practical lesson for today. Pokemon Evolution." Dragon Emperor says.

"Right." Ash and Serena reply.

"Alright. Let us start by one of you telling me the definition of evolution." Dragon Emperor says.

"Evolution is a natural phenomena where several characteristics change in living biological populations via inheritance of heritable characteristics over successive generations." Ash replies as he remembers the definition from the textbook he studied for his KIP exam.

"That is a correct definition in it's essence but it is incomplete as well. But moving on. Serena tell me the difference between Pokemon evolution and evolution of other life forms." Dragon Emperor asks Serena.

"Well Pokemon evolution has well defined stages within the lifetime of the Pokemon. For example a Fennekin evolves into Braixen then into Delphox. The pattern of stages is fixed depending on the type and species of the Pokemon. Other organisms don't change their forms within their lifetime." Serena replies.

"Good. You both are quite correct. But now it is time to study from a Pokemon Master's perspective. Are you ready?" Dragon Emperor asks them both.

Both Ash and Serena nod.

"Alright now tell me do you remember the 2 types of DNA a Pokemon has?" Dragon Emperor questions them both.

"Yup. Class DNA for the Pokemon type and Local DNA for the Pokemon's species and individuality." Ash replies quickly.

"Very good. Due to the distinct nature of the 2 types based on that Pokemon Evolution also has 2 types. First type is known as the Passive Evolution. This evolution happens in all living organisms be it Pokemon or humans or other organisms. This evolution takes place very slowly. occurring gradually over the course of thousands of years. The reason why it is called Passive is because you can't observe it with your own eyes due to it's slow characteristic changing nature. An example of this is Charizard. Like I told you Charizard used to be a Fire, Flying and Dragon type Pokemon but over the course of thousands of years it's Dragon type DNA became recessive. This is a perfect example of passive evolution."

Serena raises her hands and asks "If it can't be seen by the observation how is its existence confirmed?"

"A good question. There are several evidences. First fossil records. The fossil of old Pokemon help us in studying evolution. Then there are the similar characteristics that related species share, vestigial organs etc. Don't worry as your level as a trainer grows I shall teach you all these things." Dragon Emperor replies before pausing.

"As I was saying. Passive evolution is very slow. It has been studied and found out that Passive Evolution affects both Local and Class DNA but it's affect of Class DNA is more profound than that on Local DNA. Second type of evolution is Active Evolution. It is the normal Pokemon evolution you are used to. The one which Serena described just now. The reason why it is called Active Evolution is because it happens very fast in comparison to normal evolution which takes place over thousands of years. Now tell me what do you think causes a Pokemon to undergo Active Evolution?" Dragon Emperor asks the 2 of them.

"Well there are several reasons according to what we have studied. Firstly some times they evolve due to reaching an experience level or sometimes by using an evolution stone or an object like a Razor Fang." Ash replies.

"Indeed but how does the experience your Pokemon gains translates into Evolution? How much experience is enough to evolve?" Dragon Emperor counter questions.

"I don't know." Serena replies.

"Same for me." Ash replies as well.

"Take a guess. Any one guess." Dragon Emperor replies.

Both Ash and Serena think for a while. After a while they both shake their heads in defeat.

"Well the mechanism which enables Pokemon to evolve after gaining experience is still unknown even among Pokemon Masters. Several models and theories have been put forth but none of them is perfect. However we do know how does the Pokemon's experience translates into the level at which your Pokemon currently is." Dragon Emperor replies.

"How?" Ash and Serena ask in unison.

"The answer is Aura." Dragon Emperor replies.

"Aura?" Serena says in surprise as it is the first time she is hearing this term.

"I don't know much but my friend Brock told me that it is a form of spiritual energy which resides in all living things in the known universe." Ash explains to Serena.

"Yes you are right. But it is so much more than that." Dragon Emperor replies before smiling.

"Tell us." Serena says with an inquisitive tone.

"After years of study and observation it was found that whenever a Pokemon gains experience it increases the level of Aura associated with that Pokemon. The Local DNA of the Pokemon is closely linked with the Aura level associated with the Pokemon. Whenever the Aura level crosses a certain threshold value it triggers a mutation of the Common Local DNA segment of the Pokemon. This mutation is what changes a Pichu into a Pikachu, a Fennekin into Braixen and a Ghastly into a Haunter." Dragon Emperor says before taking a pause.

"Wow. I didn't know that Pokemon had such a complex mechanism for evolution!" Ash says with eyes twinkling in excitement.

"Of course. You are training as my apprentices. Did you expect anything less." Dragon Emperor replies with a chuckle.

"But what about a Pokemon egg. How does it change it's form. I am confused. There is no way for it to gain experience." Ash asks.

"We will come to Pokemon eggs a little later when I tell you about how evolution and reproduction are linked. Now coming back to where we were. The mutation triggered by crossing of the aura threshold level. But there are several questions which arise. Such as how does the mutation of the complicated Common Local DNA change into it's next form without incurring an error? How does a Charmander's DNA know to change into Charmeleon's DNA and not a Charizard's DNA? etc."

"Yup all those are valid questions." Serena remarks.

"The answer lies in the Different Local DNA. This segment of DNA is not only responsible for controlling a Pokemon's individuality but also stores all the information regarding the Active evolution. There is a gene called Evolution Regulatory gene which is located in the Different Local DNA and an Aura Threshold Gene which is located in the Common Local DNA segment. Evolutionary Regulatory gene is responsible for translating the level of the experience the Pokemon has gained and transmitting this information to Aura Threshold gene. It also tells how the mutation of the Common Local DNA will take place. The Aura threshold keeps track of the level of Aura the Pokemon has. After crossing the Threshold it sends a signal to the Evolutionary Regulatory gene to transmit the information of the way in which the Common Local DNA is supposed to undergo mutation for the evolution to take place."

"I am extremely confused." Ash says with a blank expression.

"Me too." Serena replies.

"Alright. Let us understand it via an example. Take Fennekin. Whenever Fennekin gains experience by either learning a new move or by deepening the bond with it's trainer or any other way that increase in experience is noted by the Evolutionary Regulatory Gene. With me till here?" Dragon Emperor says.

"Yup." Ash and Serena reply.

"Alright now whenever there is an increase the Evolutionary Regulatory Gene will send the new updated increased Aura value to the Aura Threshold gene. Once it gets the new value it will first update the current value it is holding and will check whether the new value is greater or equal to the threshold level or not. With me so far?"

Both Ash and Serena nod.

"In the case the new value is less than the threshold value. Then nothing happens. But if it is greater than the threshold value then it sends a signal back to the Evolutionary Regulatory Gene telling it that the time for evolution has come. When this happens. The Evolutionary Regulatory gene sends the way in which the current stage's Common Local DNA needs to change to the next form. This is why a Fennekin always changes into a Braixen and not a Delphox. With me still?"

"Yup." Ash replies.

"Good. Now when this happens the mutation occurs because the increased Aura energy level transforms it into the next stage. The entire Pokemon's body s flooded with the Aura Energy causing it get seen from outside by a blinding flashing white light while the evolution takes place. After the evolution takes place the Evolutionary Regulatory gene updates itself with information of how to mutate the DNA for the next evolution when the time comes." Dragon Emperor says before drinking some water.

"Alright. Before we take the lesson further both of you tell me what I have discussed so far. you have 10 minutes go." Dragon Emperor says.

(15 minutes Later)

"Excellent job. You are both very bright to pick up such an advanced concept so quickly. Now let us discuss another interesting scenario. Which is what happens when evolution stones are used?"

Both Ash and Serena nod indicating that they are ready to go on.

"When an Evolution stone comes into contact with a Pokemon. The energy emitted first comes into contact with the Class DNA of the Pokemon. Tell me why do you think it does that?" Dragon Emperor asks Serena.

"I don't know." Serena replies.

"It does so for verification purposes. Remember a fire stone only works on fire type. It does not work on water types. If it does that would be an anomaly condition. When the energy emitted from the evolution stone of the correct stone comes in contact with the Class DNA of the correct type it gets transformed into a mixture of the signal which is sent from Aura Threshold gene to the Evolutionary Regulatory gene and Aura Energy. Then " Dragon Emperor says before being cutoff by Serena.

"the signal reaches the Evolutionary Regulatory gene which sends the mutation information to Aura Threshold gene. The Aura Energy produced along with the signal compensates for the lack of Aura energy levels in the Pokemon originally before the evolutionary stone was used thereby triggering the evolution." Serena says completing the Dragon Emperor's statement.

"Excellent. I now see that the 2 of you are now starting to evolve as well. You will go far." Dragon Emperor says while giving them both a smile.

Ash and Serena both beam at being complimented and give each other a high five.

"But you told us that the mechanism is not known among Pokemon masters. But here you just described it in detail. I don't understand." Serena says

"What I have told you is just a skeleton. The details are still unknown. We still don't know how the experience level is translated into Aura level by the Evolution Regulatory gene? How does the Aura Level trigger and cause the mutation? How does the information regarding the next level of mutation get updated into the Evolutionary Regulatory Gene after evolution takes place. In other words when Fennekin evolve in Braixen from where does the Evolutionary Regulatory Gene get and store the mutation information for next evolution into Delphox? etc." Dragon Emperor says before pausing.

"Alright." Serena says while in a way wishing she hadn't asked the question in the first place.

"Now all this is fine when the Pokemon can evolve. But when a Pokemon has reached it's final evolutionary stage something very unique happens. In this case the Evolutionary Regulatory gene gets transformed into a Mega Evolutionary Regulatory gene." Dragon Emperor replies.

"So this is why only Pokemon in their last evolutionary stages can Mega Evolve. Because only they have the Mega Evolutionary Regulatory gene!" Ash exclaims.

"Yes you are absolutely right. But the mechanism is quite complex and we will need at least 2 days to discuss it. That is meant for a later time." Dragon Emperor says.

Ash and Serena nod. Dragon Emperor opens his mouth to speak again when he suddenly closes it and starts looking around here and there in a restless manner. Ash and Serena both look at each other confused. They turn to see Dragon Emperor with his eyes closed and signs of restlessness on his face.

"What happened Dragon Emperor? Something wrong? Did we do something?" Ash asks in a concerned tone.

"No. No. Nothing like that. It's just that I feel a minor disturbance is all." Dragon Emperor replies while opening his eyes but his restless face still the same. He silently thinks for sometime while Ash and Serena give strange glances at each other.

'What's Happening?' Ash mouths to Serena without making a sound.

'I don't know.' she mouths back in equal silence.

Suddenly Dragon Emperor shouts "Of course. That's it." causing both Ash and Serena to jump in surprise for a second.

"What happened Dragon Emperor?" Ash and Serena ask in unison.

"Your eggs are going to hatch in a few moments. No wonder I was feeling a disturbance." Dragon Emperor says while relaxing his face.

Ash and Serena both still look at Dragon Emperor with a confused expression as they still have no clue what he is talking about. Dragon Emperor looks at them staring at him.

"Well don't just stand there and gape at me. Go to your eggs now. You need to keep them warm." Dragon Emperor says in a loud enough tone to snap them out of their daze.

"Right." Both of them say as they turn around and run towards their tent a little distance away.

(30 Minutes Later)

"Wow. These are just the best. Thanks Dragon Emperor." Ash and Serena says as both Alolan Vulpix and Rockruff are affectionately nuzzling with them both.

Dragon Emperor smiles. Then he says "Well I still had a lot to cover but since we have 2 new members to welcome to the family we shall call it a day after one last topic. Here put them in these Poke-balls." while handing Ash and Serena a Poke-ball each.

"OK." They reply as their Pokemon willingly go inside their Poke-balls.

"Alright. Now for the last topic of the day since we had 2 Pokemon born we will talk about the genetics of Pokemon reproduction."

Ash and Serena raise an eyebrow at the mention of reproduction but they quickly recover and indicate to Dragon Emperor to start.

"Pokemon Reproduction is just like Human Reproduction. The physical process is the same. What we will be talking about is how the DNA is involved and how the evolutionary inheritable characteristics are inherited. Alright tell me what do you know about human reproduction?" Dragon Emperor asks Serena.

"U mm. Well we have 2 partners. One male one female. The male deposits the sperm into the vagi... "Serena says before being stopped by Dragon Emperor.

"I didn't ask for physical dynamics. I am well aware you 2 are thorough on the process and the machinery involved at a personally experienced level. What I need is the dynamics of the DNA that is passed from male and female to child." Dragon Emperor says causing both Ash and Serena to flush red.

Ash is the first one to recover. He says "Well. I don't know the complete details but the mother and father each give one half of their DNA which is then combined into the genetic makeup for the child."

"Correct. As you know in humans the sex of the child is determined by the sex chromosome of the father. However in Pokemon when it comes to the sex there are certain exceptions. Firstly in Pokemon it is the sex chromosome which is located in the Different Local DNA of the Pokemon which determines the sex. The concept for sex determination in the offspring of the Pokemon is the same as in humans. I will leave that research part for you to do. But now the exception comes when the evolution is sex determined. A good example of this is the evolution of the Pokemon Burmy. Burmy's evolution is determined not only by it's location of evolution but also it's gender. Female Burmy will always evolve into Wormadon whose abilities can differ based on the location. Male only evolves into Mothim. Another interesting thing to observe is that Wormadon is always a Dominant bug type. But it's other Dominant trait and its special ability is determined by it's location of evolving." Dragon Emperor says before pausing.

"Right." Ash and Serena say in unison.

"Good. Now this is the end of today's lesson. There are several things to study in it. For example I was surprised that none of you asked me about Eevee's evolution pattern. But anyway you will learn all that later. I must say I am very pleased with your performance in my test." Dragon Emperor says.

"What test?" Ash and Serena ask in unison.

"Do you remember yesterday I taught you 3 lesson when you tried and failed to shred the leaf with your punch?" Dragon Emperor asks the duo.

"We do. Why?" The reply.

"The reason why I took your theoretical class on Pokemon Evolution was to test whether you had actually imbibed the 3 lessons. I on purpose taught you a complicated and a relatively useless theoretical lesson with regards to Pokemon battling to see whether you had the will, perseverance,and determination to assimilate it. To my delight you both did very well. As a reward from tomorrow we shall shift to a theoretical battle strategy lesson. We shall cover everything related to Pokemon training in the theoretical lessons as far as possible. In due course I shall also introduce Mega Evolution and Z-Moves into your battling styles." Dragon Emperor says with a broad smile.

"Thank you. We only did so well because we had a good teacher." Ash and Serena reply with bowed heads.

"Humble and flattering at the same time. You two are quite the pair aren't you." Dragon Emperor says with a chuckle while tossing 2 Poke-balls releasing Aerodactyl and Dragonite.

"Go get your Pokemon back. I will go fetch Clemont and then we shall call it a day. Now be back as soon as possible." Dragon Emperor says.

"Right. See you soon." Ash and Serena say as their Pokemon take flight.