“Hello, everybody!” Twilight twirled a telescoping pointer rod in her magic, ready to lecture. “Today, we’re going to be talking about some of the summits!”
A chalkboard rolls into view, and on it are four drawings. “There are four summits. Horn growth, body growth, wings, and mane.” The pointer stops at each as she talks. The first is of two horns, one small and one long. The second is of two pony bodies, one small and one alicorn-sized in proportion. The third is of an appearing set of wings, while the fourth is of Celestia’s ethereal mane.
“Horn and body growth happen slowly over time, growing like any body part would while going to adulthood. The summit for these are ‘dominated’ when an alicorn ascendant finishes growing in these aspects.” Twilight looked down at her body. “Speaking as the shortest of the Elements of Harmony, I think I have a rather long way to go on the body growth one. Or maybe I’ll just be short forever. But is ‘short’ for an alicorn all that different from baseline normal?”
Celestia stepped into the room. “I can help with that one.” The wall behind her, including the chalkboard, faded to black, then quickly changed to show a blue sky with clouds. Embedded in the image were the silhouettes of twelve other alicorns, though few details could be gleaned other than the fact that they were alicorns.
Twilight held her head with her hooves. “Ack! How-- I was using a chalkboard! How did you--!?”
“Special, ancient alicorn secret.” Celestia winked. “Anyhoof, you can see that there is a bit of a size variance between the alicorns of the past. Some, like Lord Glacien, were quite large. Even larger than I. Others weren’t near as big. However, it is important to note that every one of them was still larger than what one would see in a regular pony. Perhaps some extreme examples of single-tribe draft ponies do exist that are near our size, such as General Stone, but these are extremely rare.”
Twilight coughed and straightened her mane. “Yes. Right, well. There is one other thing. The horses in Saddle Arabia are unique and are all quite tall, but like zebras, they are a separate subspecies from we ponies. Despite our similarities, we cannot breed with them, so our heights never equalized.”
“My little Twilight, thinking about breeding?” Celestia smirked.
Twilight squeaked and blushed bright red.
The Princess leaned down to her ear. “Did that ambassador leave such an impression on you, my student? I could arrange for another visit, if you like.”
Had she already been taller, Twilight could’ve passed for Big Macintosh given how red her whole body was. “Ack! No! Bad! Bad thoughts!” Her hooves went up to cover her ears. “Lalalalalalalalalalala….!”
Celestia smiles at the camera. “We’ll be back later to explain the others, everybody.”