This might be my last post for a while: tomorrow I'm off for six weeks of lizard hunting on Hispaniola, four in the Dominican Republic and two in Haiti.
Our first stop will be the Recodo Road, a locality made famous by the studies of the late Harvard Professor and and godfather of Anolis lizard biology Ernest Williams. Our first step will be to see how far up the road we can go; as Williams noted "there are no problems other than two fords, the first possible in a rented car, the second not so." In spite of this challenge, anole populations along the Recodo road have a history of yielding insight into the role of the dewlap in anole communication and speciation.
It was along the Recodo road that Williams and his students discovered some unusual trunk-ground anoles that could only be distinguished from the widespread Anolis cybotes by their striking purple and red dewlaps. They turned out to be a distinct new species - Anolis marcanoi - and one of the first whose validity was confirmed via molecular genetic analyses. Later, an experimental behavioral study - which remains one a few of its kind - suggested an important role for dewlap divergence in dictating the nature of interspecific interactions between A. cybotes and A. marcanoi, and marked a career beginning for the man who has assumed the anole throne at Harvard.
We'll be looking at an even more interesting species complex of trunk anoles that also attracted the attention of Williams and his students (see attached figure from the 1977 Anolis newsletter). Unfortunately, the main architect of this work - Preston Webster - died tragically before completing his thesis. Although incomplete, his work marked the high point of the Williams lab's foray into molecular analyses of species and speciation. Webster's preliminary field and allozymic studies were published posthumously in the third Anolis newsletter and got far enough to reveal evidence for two intriguing patterns: habitat-mediated dewlap divergence (a key to ecological speciation) and reproductive character displacement (perhaps driven by selection against hybridization events that were shown to produce sterile male offspring). Although these observations prompted Williams himself to suggest that there "are obviously several problems here crying for solution", they have remained unexplained for more than three decades.
It never hurts to go into a field trip with the blessings of the godfather...
Anole Embryos Don’t Mind the Heat
1 day ago