That is interesting. I have a little understanding of the different causes for tusk differences. The tusks are after all a modified tooth and elephants dont have orthodontists ! These examples are the hillbilly bubbas of the elephant world !
1/ Tuskless-this is usually genetic. It is more common in cows. Zimbabwe does have a fair number, enough to issue specific licences and you can see that it is often passed mother to daughter. Even though they have been targeted for removal for many years, the genes still persist. Bulls are less common but again genetic.
2/ 4 tusks- That is pretty amazing and those examples show that it is likely to be genetic. those are fully formed tusks, not a tusk split or damaged. I have read of damaged tusks growing in a sort of bundle-obviously damaged early in development.
3/ The deformed tusks are surely some damage or disease of the tusk/root or bone. Disease can also prevent the growth of the tusk completely.
Played rookie league for the Yankees in Paintsville after winning the College World Series at Fullerton State, in1979. All I could think about was the movie “Deliverance”- lived up in a hollow with some other players. Refused to go on a moonshine run because it was a dry county-no way. Met some of the nicest people on the planet there! Van Lear the home of Loretta Lynn was highlight of summer LOL.
Mule deer and Colorado elk seasons almost done! Hunters driving farm roads, looking for racks, their PH driving them along, I ask that you not pull into my drive. The buck behind me, on the boundary line of the GMU somehow knows. The hunter laughs, I would invite you in to see my Searcy rifles but social distancing prevails, darkness arrives and the buck slides away into secret tree grove...