Category: Natural History Observations Page 26 of 34

In September, 2011, Alex Dornburg (Yale), Andy Jones (Yale), Teresa Iglesias (UC Davis), Dan Warren (UT Austin) and I made our yearly pilgrimage to study the marine and herpetological fauna of Curaçao. On the advice of J. Losos, one of our missions this year was to document the dewlap color asymmetry in Anolis lineatus.

In 1967, Stan and Patricia Rand published a paper on the natural history of A. lineatus and noted that:

“The dewlap is large in the male; extended it has a wide border with bright orange skin around a block central spot. The spot is crossed by several widely separated rows of white scales. The border on one side is closely set with yellow or whitish scales, on the other side, the scales are rudimentary and colored like the skin. About half the males have the scales well developed on the right side of the dewlap, about half on the left… one side of the dewlap appears to have a bright orange border, the other side a yellow orange border. The females have a much smaller dewlap, but colored like the males’ and also asymmetrical, though less conspicuously so.”

We braved multiple attacks of push-ups and head bobs and managed to collect and photograph multiple individuals.

Note the large, white scales in the orange field of the dewlaps:

versus the other side of the dewlap which lacks the large, white scales:

The orange vs. yellow-orange difference is a bit subtle and not easily visible in these photos, but it’s there.  Like Rand and Rand, we found a roughly equal distribution of individuals with the white scales on the left, and those on the right.

What explains this asymmetry?   Are they using the different colors to warn males and attract females?

We are thinking of hypotheses to test during our 2012 trip to the island and we’d appreciate hearing other ideas from other researchers.

Illustrations by A. Seago

Here’s another highlight from the collection of videos that the Glor Lab recorded during an expedition in the summer of 2010 (see our previously posted videos of a fight, color change, and mating).  This video is an interaction between a male Anolis distichus and a caterpillar.  This interaction left one of the participants with a good meal and the other, well, let’s just say he’s a part of the circle of life.

Here’s a close up of the Anolis hendersoni I found sleeping one fateful night inside the Dominican Republic.

Anolis hendersoni - male

Prior to finding this species, I had spent the evening looking for Sphaerodactylus armstrongi and S. streptophorus on the northern slopes of the Sierra de Bahoruco NW of Puerto Escondido.  Upon entering a patch of closed-canopy, broad-leafed forest with a dense, bushy understory, I remarked to myself, “I bet there will be Anolis bahorucoensis here.”  Anolis bahorucoensis is a bush anole that is common across the Sierra de Bahoruco, and often found alongside S. armstrongi.  I was not expecting to see A. hendersoni – another dolichocephalic bush dwelling species that is closely related to A. bahorucoensis – because it is generally considered a Haitian endemic whose range doesn’t cross the border into the Dominican Republic. When the sun set and I switched over to night hunting, I was happy to find out my intuition was, for once in my life, a close approximation of reality.

Anolis carolinensis hatchling in our animal facility.

I’ve noticed that many of the anoles in my breeding colony occasionally have white protuberances emerging from their nostrils, like the two-month old hatchling to the left. I haven’t been able to determine whether these protuberances are the remnants of an old shed or whether the lizards have a fungus growing in their nostrils. By the time I catch an afflicted individual in its cage the protuberances are gone, seemingly because the lizard blew them out while moving to evade my hand. Has anyone experienced this phenomenon?