Doing a project, need help!!!
Because different animals grow in different places and the way to handle that meat depends on the area, sometimes tradition, sometimes climate, sometimes some other factor.
One example: prosciutto is made in many places in Italy, but the saltiness of the final product is closely tied to the climate. In warmer climates, the temperature doesn't get as cold, so more salt is added to prevent spoilage.
In some cases, the end results are different because different animals are used. A pig in Northern Germany may not taste like a pig from Tuscany because those animals are living in different places, eating different things, are different breeds, etc.
Preserving meat is one of the oldest practices for extending the usefulness of livestock. When people have been doing things for a really, really long time, it is natural for things to be different from one place to another. Look at language, music, art, architecture, fashion. This diversity is not limited to preserved meat.
Thus, the topic really can't be adequately discussed in a food Q&A forum such as the Food52 Hotline. I suggest you go to the library and check out some books on charcuterie.
This forum is more suited to handling questions about recipes or specific cooking questions.
and the anthropologist in me finds that so many of the same preservation methods are found in different parts of the world, developing independent of each other.
It doesn't surprise me. After all, there were only a handful of techniques available to pre-industrialization people to preserve meat: smoking, salting, drying, etc.
The more interesting inquiry would be whether or not disparate groups discovered these techniques at relatively the same moment. My guess would be no, but I'm no expert on such matters.
Perhaps it has been studied before and even documented, but as we know, some cultures have scant or missing written historical records due to various circumstances (weather, climate, conflict, etc.).
There've been a lot of hungry people for a long time, and most of them haven't had freezers. Nomadic peoples, which was all of us until relatively recently, also have portability issues. Sausages in particular have also become a practical and versatile way to create flavorful foods out of humble (and at times appalling) ingredients.