This are probably cristate or fasciate growth - fairly common and actually desired (by some) in succulents http://davesgarden.com/guides/articles/view/3448/#b . It's not completely understood why it occurs or what is actually causing it. Maybe more accurately is that some of these growths are known to be mutations, others caused by bacteria or viral infections, and others are other environmental causes, but that most are unknown. My guess is that this one is not really a mutation (genetic aberration) but a developmental malfunction in the apical meristem. However it would be really difficult to determine what the cause is. Usually these don't carry to the next generation. The only way to keep something like this going is to propagate by cuttings. However if you do get seeds to form - and grow them out - and these show similar growth - that would likely mean it's genetic.
I have tomatoes that occasionally do this - usually the potato-leaved and very large types - but only near the end of a stem. I've seen sunflowers and dandelions with this too.
Here's a wiki on this too http://en.wikipedia.org/wiki/Fasciation
I have tomatoes that occasionally do this - usually the potato-leaved and very large types - but only near the end of a stem. I've seen sunflowers and dandelions with this too.
Here's a wiki on this too http://en.wikipedia.org/wiki/Fasciation
