Do Minecraft updates change Biomes?

I have a survival world that I created back somewhere between 1.8 and 1.9. I also have a copy of that world in creative mode, made around the same time, that I use for testing builds and finding biomes. In both worlds I found a Jungle biome. I had to cross a Savannah, a Mesa, and a Desert in that order, but it was a relatively short horse ride straight south of my base. Due to some real life issues I haven't played since 1.9, but I picked it up again this month. I tried to find the Jungle biome again so I could get more saplings and cats, but it's just… Gone? The Savannah, the Mesa, and the Desert are all still there, exactly as I left them, with torches thrown here and there, blocks missing, and temples and villages raided. But I can't for the life of me find the Jungle. I've spent hours looking in both creative and survival. It's literally gone. The Desert stops at a huge sea I don't remember seeing before. What the heck is going on? Have the new updates changed the biomes? Remember it was just straight south of my base so I know I'm not just going the wrong way.