Tag: anole behavior

Evolution 2019: How Should We Predict the Impacts of Climate Change on Anoles?

Climate change on earth is accelerating. These changes will have important impacts on all species, but some types of organisms are predicted to be affected more strongly than others. One such group is ectotherms which use the temperatures available in surrounding habitats to regulate their body temperatures. Another such group is mountaintop endemics. These species are restricted to one or several mountain peaks by climate and/or competition with other organisms. As such, they cannot easily disperse to other areas if climate makes their current habitat unsuitable!

Mountaintop endemic species may be particularly vulnerable to climate change (Chand Alli, CC BY SA).

Predicting how climate change will impact ectotherms and montane endemics has become a proverbial “hot topic” in recent ecological work, with studies focusing on lizards, salamanders, plants, and insects among other taxa.

Hispaniola contains several high elevation areas home to mountaintop endemic species, including anoles (NASA).

Many studies use correlative modeling approaches (often termed ecological niche models [ENMs] or species distribution models [SDMs]) to assess a species’ current distribution and predict its future distribution by projecting it into simulated future climate scenarios. This approach has some advantages including ease of implementation across many species. However, it has at least two potential drawbacks: the environmental data used in building such models are often measured at a fairly coarse scale that does not represent how many organisms use their environments, and the models do not explicitly include biological processes such as physiology and behavior.

Anolis armouri in a montane rock meadow (Reptile Database).

Vincent Farallo, a post doc at Virginia Tech, and his advisor, Martha Muñoz (both moving to Yale in a few weeks!), investigated whether incorporating physiology and behavior into  modelling might affect predictions of climate change impacts on two mountaintop endemic anoles of Hispaniola, Anolis armouri and Anolis shrevei. Correlative SDMs (via BioMod2) predicted both species would lose much or all of their suitable habitat under climate change, perhaps leading to extinction. However, when Vincent constructed mechanistic niche models (via NicheMapR) that included knowledge about the thermal physiology and habitat use behavior of these species to predict activity time, they showed that habitat would increase in suitability under climate change, the opposite result! Interestingly, these models also predicted increased suitability for a widespread anole, A. cybotes. This result suggests that while climatic changes may not be a direct threat to these mountaintop anoles, increased competition with another anole, an indirect impact of climate change, may be.

Activity time of Anolis shrevei is predicted to increase across its range in Hispaniola with climate change (Farallo and Munoz).

As a whole, Vincent and Martha’s work shows that incorporating more mechanistic knowledge into models, including physiology and behavior, may be critical to predicting the impacts of climate change on organisms and making sound conservation decisions.

Three in The Bed: a Curious Case of a Shared Sleeping Perch in a Neotropical Anole

Opposite views of a communal sleeping event (1 male, 2 females) of Anolis cusuco at Parque Nacional Cusuco, Departamento Cortes, Honduras (Brown & Arrivillaga, 2018)

Let’s be honest: anoles are fascinating! These charismatic and well-adapted lizards are always a pleasure to watch and document. Better yet, no matter how well you think you know a species, they’re still always full of surprises.

The sleeping behavior of anoline lizards is a fascinating aspect of their natural history, and a growing amount of literature has detailed species-specific sleeping activities.  Typically, anoles are considered solitary sleepers owing to their territorial nature,  but ‘behind closed doors,’ this may not always be the case!

For those curious,  a recent  ‘behavioral oddity’ published in Mesoamerican Herpetology  by Brown & Arrivillaga (2018), reported an example of three individual Anolis (Norops) cusuco sleeping together on a perch! The individuals were so close that portions of their bodies overlapped! Strange, indeed; this observation contrasts the typical view of anole sleeping ecology, territoriality and indeed that what is known for this species (Clause & Brown, 2017).  In over 5 years of visiting Cusuco NP (observing countless solitary sleeping A. cusuco), imagine the surprise in finding these anoles having a sneaky snuggle!!

As we wrote: “Although a conclusive explanation is not available, we suggest that because the sleeping group consisted of one male and two females, that the shared perch might have been breeding-related. This situation might be associated with the overlap of male and female territories, or by the anoles awakening close to necessary resources. Conceivably, however, courtship might have been interrupted by nightfall, and the orientation of the sleeping male ensured that courting would continue the following morning.”

 

Registro de Copula de Anolis huilae

Copula de Anolis huilae en Ibagué (Colombia).

Copula de Anolis huilae.

En el marco de mi tesis de maestría sobre la Ecofisiología térmica de Anolis huilae tuve la oportunidad de observar, creería que sería el primer registro, una pareja de ésta especie copulando en el tronco de un árbol. Evento que lo considero relevante por la falta de información acerca de ésta especie.

El estudio lo estoy desarrollando en el Corregimiento de Juntas, Ibagué (Colombia). Mi objetivo es conocer aspectos de la fisiología térmica de A. huilae y relacionarla con las temperaturas ambientales y microambietales de su hábitat.  Para la colecta de datos me estoy apoyando con una cámara termográfica infrarroja (metodología no invasiva) y modelos de cobre con data loggers insertos en ellos.

Imagen termográfica de copula de Anolis huilae.

Imagen termográfica de copula de Anolis huilae.

En una primera etapa del estudio estoy averiguando si A. huilae es una especie heliotérmica o tigmotérmica; como también, si es termoconformadora activa o termoconformadora pasiva. Datos que próximamente los compartiré.

Observaciones comportamentales, no registradas,  ayudarán a conocer más aspectos de la biología y ecología de ésta especie, de la que aún falta mucho por descubrir. Así mismo, he observado en esta localidad la simpatría con otro anolis, Anolis antonii.

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English translation via the internet:

Record of Copulation of Anolis Huilae

In the framework of my master’s thesis on the thermal ecophysiology of Anolis huilae, I had the opportunity to observe, you would not believe that would be the first record, a couple of this species copulating in the trunk of a tree. Event that is considered relevant by the lack of information about this species.

The study, I am developing in the Corregimiento of seals, Ibagué (Colombia). My goal is to understand aspects of the thermal physiology of A. huilae and relate it to the ambient temperatures and microenvironments of its habitat. For the collection of data I am supporting with a infrared thermal imager (non-invasive methods) and copper models with data loggers inserts in them.

In the first stage of the study, I am enquiring whether A. huilae thermoregulation is a species or is thigmothermic; also, whether it is an active or passive thermoregulator. I will share the data soon.

Behavioral observations, unregistered, help you learn more aspects of the biology and ecology of this species, which still lack much to discover. Also, I’ve seen in this locality the sympatry with another anole, Anolis antonii.

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