I’m doing fieldwork with Anolis sagrei in Gainesville, FL, this summer. We now have about 125 lizards measured and marked, and have come across a number of interesting morphological oddities in these lizards. Most interesting so far is this doubly regenerated tail, i.e. there appear to be two spots at which the tail has regenerated, which means a regenerated tail must have broken and regenerated again.
Approximately three minutes before we noticed this tail, my field assistant Christian Perez asked me if double regenerations were possible, and I confidently said “no.” As Jonathan Losos puts it in Lizards in an Evolutionary Tree, “when a tail regenerates, the new portion of is made of a rod of cartilage and thus lacks the intravertebral breakage planes that enable an unregenerated tail to autotomize.” So how did this double regeneration happen? Anyone seen this before?
The next oddity is this male with a mysteriously shortened upper jaw:
Third, we have a partially discoloured dewlap: