Category: All Posts Page 56 of 148

SICB 2018: Predicting Climate-Induced Distributional Shifts for Puerto Rican Anoles

Anna Thonis, a Master’s Student in the Lister Lab at Rensselaer Polytechnic Institute, used distributional projection models to predict future ranges of anoles in Puerto Rico. There are ten species of anoles in Puerto Rico, and all of them are predicted to be faced with range shifts in the coming years due to climate change, as Puerto Rico may be faced with both warming and drying out in the future.

Thonis used population occupancy data collected by Lister from 1976-2012 as an input for her models. Using climate models and open source software, Thonis projected anole populations for 2050 and 2070. Based on these models, there will be an average reduction of the most suitable of anole habitats of 29.5% by 2050, and 8 of 10 anole species in Puerto Rico face habitat reduction. In 2070, the models predict and increase in habitat reduction, with a 39.6% reduction in the most suitable habitat and 9 of 10 species of anole facing habitat reduction.

Though these models sound dismal for anoles, Thonis hopes that future work with distributional models can help inform conservation decisions as climate change processes. More detailed models may be able to inform decisions on where protected habitats for anoles should be placed.

SICB 2018: Do back-pattern morphs in female brown anoles differ in morphology, behavior and natural selection?

Sometimes, males and females of the same species differ in traits linked with their ability to survive and reproduce. These differences, called sexual dimorphisms or polymorphisms are quite common in lizards, including anoles! Female brown anoles have a polymorphic back pattern while males are usually of a single pattern. A lot of work has tried to uncover why this back pattern polymorphism exists in nature and what advantages it offers these lizards. Rachana Bhave, a Ph.D. student with Robert Cox at the University of Virginia were interested in determining just how these male and female-like morphs of brown anoles differ in their morphology, behavior, and which traits influence survival.

Using a captive island population in Florida, Bhave et al. captured all of the lizards on the island and measured differences in morphology between the morphs, finding that female-like morphs tend to have higher survival as juveniles but not as adults. These morphs differed in their growth rates but did not experience different selective pressures, indicating perhaps a very complex control regulating the back pattern maintenance in this population. They also found that while female-like morphs tend to display at a higher rate, there weren’t any differences in the morphs probability to attack. They plan to integrate more physiological data such as growth or performance metrics to try and uncover the governing factors responsible for maintaining this back-pattern polymorphism. Awesome stuff to come!

SICB 2018: Environmental Factors Affect Aggression in the Brown Anole

Male-male competition is one of the most widespread phenomena in lizards. Males compete for access to critical food resources, territory space, and female lizards, making a male’s ability to win competitions against other males critical to survive and reproduce. However, how the behavior of a male can vary depending on what social environment he grew up in, the abundance of certain predators or competitors, or the density of other male and female lizards. Therefore, determining what environmental factors influence the behavior of male lizards as they attempt to procure resources necessary to survival and reproduction is a critical question in biology today.

From Virginia Tech, (now a Ph.D. student with Shawn Kuchta at Ohio University) Emily Watts and her collaborators sought to understand what environmental factors influence the behavior of male brown anoles (Anolis sagrei). They used males reared in a common garden from four different populations in the Bahamas to try and determine if genetic or environmental factors influence the aggression differences among males of different populations. Using male-male competition experiments and mirror experiments (where a single male perceives himself as a rival), they tested the hypothesis that males reared in a common garden will not differ in aggressive behavior. They found that aggression varied significantly among populations when using mirror tests, but they found support for their original hypothesis when using male-male competition experiments. This work highlights that aggressive behavior of males is shaped by a multitude of pressures from the environment, to genetics, and ultimately how and where a lizard develops to adulthood. More is to come as they continue to increase the number of their experimental trials with more Anoles!IMG_3929

The Location of the (Neo)Type Specimen of Anolis carolinensis

Bryan Stuart, Curator of Herpetology at the North Carolina Museum of Natural Sciences in Raleigh, recently posted this on Facebook:

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And an important comment on the FB post from Jeff Beane, the department’s collections manager:

“And the neotype of Anolis carolinensis is now NCSM 93545.”

Spiders Eating Anoles and Frogs

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What a horrible way to go! We’ve reported on this before [e.g., 1, 2, 3], but not Folt and Lapinski have published a nice review in Phyllomedusa of wandering and orb weaver spiders eating frogs and lizards in Costa Rica.

The Brown Anole: A Proud Texan

From the pages of the San Angelo Standard Times:

Wild About Texas: Brown anole got to Texas as fast as it could

Living in the day and age where memes on social media are the prevailing means of communication does have a FEW benefits. I can almost always count on having a good laugh daily at something someone has posted.

Just the other day, I saw a meme that stated, “I was not born in Texas, but I got here as fast as I could!” As a naturalist, all I could think about when I saw this posted was one particular species of lizard that has found its way here, and that species is the brown anole.

The brown anole (Anolis sagrei) is one of two species of anoles that currently reside in Texas, but this species is not native to this state. First established near Houston in the 1970’s, this species was known only from areas around Houston, San Antonio and Brownsville as late as the turn of the century.

However, now it can be seen in and among most metro areas within an imaginary triangle that pinnacles in the DFW area, east of I-35 and west of I-45. It has only recently been observed (2016) in the Metroplex, and there have not been enough observations to verify whether there is a breeding population there or not. Even more recently, a smattering of individuals had been reported from a nursery in the city limits of Midland and these observations have been verified.

Originally native to the Bahamas and Cuba, this species has been introduced and is thriving in areas outside of Texas as well. It is arguably the most common lizard observed throughout the southern 2/3 of Florida, and it can also be seen throughout the eastern seaboard of Mexico.

The habitats that this invasive lizard prefers are settings in densely vegetated areas. Although occasional specimens are discovered basking and foraging in short shrubs and trees, the vast majority of sightings are of individuals in terrestrial settings. It is the propensity for living among ornamental plants and shrubs that has enabled this species to thrive in the warmer climates outside of its natural range. Therefore, many Brown Anoles are observed living around landscaped human habitations such as houses and even businesses.

The brown anole is among the most plainly colored and yet most intricately patterned lacertilian species in the United States. Unlike the native green anole (which can vary in coloration from green to tan to brown), this anole is always a shade of brown. The scales on the back are small and granular in appearance and texture, and females are often plainly patterned, adorned only with a light stripe that runs lengthwise down the spine. Males on the other hand are patterned with an intricate array of lightly outlined dark wedges and blotches along the spine.

Both species have varying amounts of dark striping that extends behind the eyes. Males have a brightly colored dewlap that, when extended, is dark red. The limbs are long, and are often colored patterned with dark stripes or bands. The head is not nearly as elongated like the green anole and is not noticeably separated from the body, and the tail, which is colored like the back, is about one-half of the 8-inch total length.

Brown anoles, like other lizard species, are “cold-blooded”, or ectothermic. This means that it does not generate heat from the inside of their body, as mammals and birds do, but rather is dependent on outside sources for heating and cooling. It is active during the early mornings and late afternoons from early April to October, and like many other reptile species it avoids the hottest part of the day by resting in shaded areas. However, the fact that it resides primarily in tropical areas, it is often active throughout the year.

This species of lizard is an opportunistic carnivore, feeding primarily on small insects such as moths, butterflies, crickets, grasshoppers, beetles, and the like.

The brown anole is oviparous, which is a fancy way of saying that it lays eggs. During the breeding season, which typically begins in early spring and extends into late summer, males will attempt to attract females by extending his bright red dewlap (a flap of skin underneath the chin) while bobbing his head up and down in a “push-up” manner.

Following successful copulations, the female will begin to lay clutches of a single egg. By laying an egg about every two weeks, a female can lay as many as 12 eggs in a season. These eggs are laid in areas of high humidity, and typically will hatch in about five weeks. The two-inch long hatchlings are smaller imitations of the female, and are capable of fending for themselves immediately.

This lizard species is a gregarious basker and will often allow people to get rather close as it relies upon its coloration for protection. However, once it feels an intruder has approached too close for comfort, it will quickly dart for cover among the leaf litter.

Michael Price is owner of Wild About Texas, an educational company that specializes in venomous animal safety training, environmental consultations and ecotourism. Contact him at wildabouttexas@gmail.com.

60% Off Anole Calendars til Midnight Tonight!

 

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That’s midnite, pacific time, so you can still make it! Go to the Anole Annals calendar site on Zazzle.com, use this code:

CALENDARS365

Night Time Activity by the Brown Anole in Guatemala

Night time’s not just for sleeping in the festive anole.

Everyone knows that anoles are diurnal, active by day and snoozing by night. Yet the rascals are opportunistic–light up the night, and they’ll take advantage to extend their carousing and foraging. We’ve had reports on such behavior before [1, 2] in the green and knight anoles (and there are more reports in the literature); now such behavior is reported in the brown anole from Guatemala, in a recent paper by Brown and Arrivillaga published recently in Mesoamerican Herpetology.

New Anole from the Tropical Andes Named after Jonathan Losos

A group of Ecuadorian herpetologists led by Omar Torres-Carvajal, in collaboration with Steve Poe, described two species of anoles from the Andes in southern Ecuador. The study was published a few days ago in the Journal of Natural History. One of the new species is unique among known species from Ecuador in that it has a blue dewlap. It was therefore named Anolis hyacinthogularis, from the Latin words hyacinthus (=blue), and gula (=throat).

AnolisHyacinthoANAN

The second species, a short-limbed lizard commonly found on twigs as far as eight meters above ground, was named after Jonathan Losos. Most people visiting this blog know who this person is, so there is not much I dare mentioning about him, except that Ecuadorian biologists were lucky enough to have him as a guest a couple of years ago, and several Ecuadorian students and scientists have been inspired by his monumental work with anoles. Besides his obvious academic merit, Jonathan has a unique sense of humor and it’s just fun to be around him in the field. Who else refers to an aye-aye as a “sinister cross between Albert Einstein and Yoda”? (Improbable Destinies). Thank you Jonathan for your work!

 

Journal of Natural History, 2017. doi:10.1080/00222933.2017.1391343

Journal of Natural History, 2017. doi:10.1080/00222933.2017.1391343

Anole Annals 2018 Calendars Now Available!

conspersus

Thank you once again to everyone who participated in this year’s Anole Annals photo contest! As usual, we received tons of great photos, and we’re ready to announce the results. First up, the grand prize winner, is the above photo of Anolis conspersus, taken by Thijs van den Burg. The second place winner is below, Anolis oculatus montanus, by Gregor Weidlich. Congratulations!

oculatus montanus

The rest of the winners are listed below, and their photos can be seen in the 2018 calendar here! Click the link to order your calendar.

Congrats again to all the winners, and happy holidays!

Winning photos:
Anolis conspersus, Thijs van den Burg
Anolis oculatus montanus, Gregor Weidlich
Anolis luteogularis, Thijs van den Burg
Anolis carolinensis, Nick Herrmann
Anolis huilae, Cristian Castro Morales
Anolis allisoni, Arnaud Badiane
Anolis wattsi. Geoffrey Giller
Anolis allogus, Thijs van den Burg
Anolis porcatus, Jesús Reina Carvajal
Anolis nubilus, Colin Donihue
Anolis grahami, Nathan Wright
Anolis porcatus, Arnaud Badiane

Page 56 of 148

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