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Song composed and performed by students at the University of Arkansas.

Just out in PLoS One. Here’s the abstract:

Microbiome studies focused on ecologically relevant vertebrate models like reptiles have been limited. Because of their relatively small home range, fast maturation, and high fecundity, lizards are an excellent reptilian terrestrial indicator species. For this study we used the green anole, Anolis carolinensis, to assess the impact of military relevant contaminants on fecal microbiome composition. Fourteen day sub-acute exposures were conducted via oral gavage with 2,4,6-Trinitrotoluene (TNT) and inorganic lead at doses of 60 mg/kg and 20 mg/kg of body weight, respectively. Body weights and food consumption were monitored and fecal samples were collected for high-throughput 16S rRNA gene amplicon sequencing and analytical chemistry at days 0 and 15. At the end of the study, liver and gut were harvested for body burden data. Chemical analysis confirmed accumulation of TNT, TNT transformation products, and lead in liver tissue and fecal samples. Bacterial community analysis of fecal material revealed significant differences between day 0 and day 15 of TNT exposed anoles with an operational taxonomic unit (OTU) within the genus Erwinia representing 32% of the microbial community in TNT exposed anoles. Predictable changes in gut microbiome composition could offer an easily assayed, noninvasive biomarker for specific chemical exposure providing enhanced scientific support to risk assessments on military installations.

Four months ago, we reported on a new species of the Chamaeleolis clade. The FB page above shows that it’s already for sale in Europe!

From Mongabay:

New findings indicate that at current deforestation rates, all of Haiti’s primary forest will be gone within the next two decades, leading to the loss of most of the country’s endemic species.

The study was authored by researchers at Temple University, Oregon State University, the U.S. Forest Service and Société Audubon Haiti, a non-profit conservation organization based in Haiti. Its results were published recently in Proceedings of the National Academy of Sciences.

By analyzing aerial photography and satellite images, researchers discovered that primary forest cover in Haiti shrank from 4.4 percent in 1988 to just 0.32 percent in 2016. They report that 42 of Haiti’s 50 largest mountains have lost all of their primary forests and the country is already undergoing a mass extinction of its wildlife due to habitat loss.

“Haiti’s recognized as having the highest proportion of threatened amphibians in the world,” said S. Blair Hedges, director of Temple University’s Center for Biodiversity and lead author of the study, in an interview with Mongabay. “And that’s largely from the deforestation.”

Other species at risk include the Hispaniolan solenodon (Solenodon paradoxus), a large shrew-like animal native to Haiti and neighboring Dominican Republic. One of the oldest mammals on the planet, the solenodon survived the mass extinction event that wiped out the dinosaurs.

But it’s not faring well in today’s world.

“It’s almost extinct,” Hedges said. “It’s very, very hard to find.” However, the team did see recent evidence of one in mountainous primary forest during a biodiversity survey that took place between 2009 and 2015.

In all, the survey turned up 28 species that are endemic to specific mountaintops – including several new frog species. Hedges says there were likely many more, but as their habitat disappeared, so did they.

“Unfortunately entire mountains have been deforested before biologists have surveyed them, so there were almost certainly many more species that we will never know about,” Hedges said.

Along with the extinctions of unique animals found nowhere else, Haiti’s deforestation has another consequence: landslides and flooding. The researchers found that without tree roots to hold soil, mountains tended to lose their topsoil to erosion soon after deforestation. And without trees to sop up rainwater, lowland areas are much more prone to catastrophic floods.

“Hundreds to thousands of Haitians die each year from flooding that is largely deforestation-related,” Hedges said. He pointed to a flooding event in 2004 that killed more than 1,200 people in a single town.

 

 

Hedges says that Haiti’s deforestation is largely driven by small-scale farming and charcoal production, which involves harvesting wood and heating it to remove water and volatile compounds. Doing this turns wood into a source of fuel that can be burned without producing as much smoke.

Around 11 million people live in Haiti, and many of them depend on wood charcoal for fuel and subsistence farming for food. As the lowlands lost their trees, people began deforesting higher and higher into the mountains.

The researchers witnessed this first-hand while conducting their biodiversity surveys, even encountering locals at study sites they had to use a helicopter to reach.

“I did a lot of hiking and we would run into Haitians at the most remote places in the country,” Hedges said.

Even protected areas aren’t immune from deforestation. Hedges recalled meeting a ranger a few years ago in Pic Macaya National Park – one of the last remaining sites of primary forest in Haiti.

“He told us that there were only 20 of them [rangers] but at any given time there are at least 200 teams of tree cutters all throughout the park – it’s a really big area – and they all have weapons, yet the rangers don’t have any weapons.”

In their study, Hedges and his colleagues write that Haiti’s two original national parks, Pic Macaya and La Visite, lost between 60 and 75 percent of their primary forest cover since they were declared protected areas 35 years ago. The researchers say improved monitoring is needed if forests – particularly primary forests – can be saved.

“Expanded detection and monitoring of primary forest globally will improve the efficiency of conservation measures, inside and outside of protected areas,” the authors write.

Monitoring forests starts with figuring out what really counts as forest, which can be surprisingly contentious. The Food and Agriculture Organization of the United Nations (FAO), for instance, defines forest as “Land spanning more than 0.5 hectares with trees higher than 5 meters and a canopy cover of more than 10 percent.”

However, according to Hedges, such a generous definition can distort the reality of a country’s forest cover and overlook primary forests, which are vital for biodiversity.

“When [the FAO defines] forests as having up to 90 percent of the trees missing, many of us would not call that forest, “ Hedges said, adding, “for a biologist like myself it’s almost absurd really.”

The FAO doesn’t plan on changing its approach to forest definition, according to Anssi Pekkarinen, team leader of the FAO’s Global Forest Resources Assessment. However, he says they are allowing “more detailed reporting at the sub-category level,” which includes differentiation of “planted forest” and “naturally regenerating“ forest.

“FAO is also working together with its partners to further improve the consistency of the reporting on primary forest,” Pekkarinen told Mongabay. “This work was initiated in 2017 and is expected to be completed within the coming years.”

In response to the country’s deforestation crisis, reforestation projects have popped up, including Haiti Takes Root and the USAID Reforestation Project launched in January 2018, which aims to plant more than five million trees.

While reforestation can have positive outcomes, Hedges and his colleagues say that preservation of primary forest is the best way to stymie extinction.

“Primary forest is critical for maintaining much of the world’s biodiversity, and its loss is the greatest threat to species survival, even if primary forest is later replaced by secondary growth,” they write.

The researchers note that even places where some primary forest is left standing quickly become un-forested due to degradation. “However, lightly disturbed habitats could provide lifelines for some species if protected and allowed to recover.”

To help Haiti hold on to its forests and biodiversity, Hedges started an NGO called the Haiti National Trust that is set to purchase a mountain in Haiti in a bid to preserve its remaining primary forest.

“Our mission is to protect the last primary forests and biodiversity hot spots,” Hedges said. “It is a big task and will require a large inflow of resources, but I remain optimistic.”

 

Citation: Hedges, S. B., Cohen, W. B., Timyan, J., & Yang, Z. (2018). Haiti’s biodiversity threatened by nearly complete loss of primary forest. Proceedings of the National Academy of Sciences, 201809753.

 

Act quickly! They’re spiffy, and make great stocking stuffers. Go to zazzle.com, search for “anolis watch.” Or follow this link. Use code “HOLIDAYZSAVE.”

Check out this photo by Tomás Michel Rodríguez-Cabrera. Here’s what he had to say: “I was by a stream at Cajalbana Floristic Reserve in Pinar del Río, when I saw the anole jumping to the water. When it came out it was carrying a topminow, Gambusia punctata, that it later swallowed.

The latest field guide to the amphibians and reptiles of Trinidad and Tobago came out in early 2018. In it, eight Anolis species were documented. My fellow contributors on this latest article published in Caribbean Herpetology now report on a ninth anole for the country: ehe Puerto Rican Crested Anole.

Most of the other introduced anoles to Trinidad and Tobago have been spreading from their first documented sighting , such as Anolis wattsi.  One wonders, how successful will these introduced anoles be in their non-native islands and what ecological effect they may have on the native fauna, including the native anoles? This is something I would like to investigate further. Any input on this from your experiences would be welcomed.

One of the most interesting patterns in the insular anole radiation is the observation that the majority of species are single-island endemics (150 of out 166 species). This observation in the Caribbean anole lizards has been known from a while and several studies have attempted to establish the underlying causes of this striking pattern (e.g., 1, 2, 3).

In a recent study, as part of my PhD dissertation, I used a different approach to try to understand why most of these species are unable to colonize other islands. I used a recently developed conceptualization to link abundances and ecological niche requirements at coarse-grain scales; this approach has been developed in the lab of my advisor (see 4, 5, 6; but see 7, 8, 9 for discussions and counter-examples; this approach has been strongly debated in the literature in the last years).

We used ecological niche modeling -ENM- to predict species’ distributions across all Caribbean islands for each species with at least 10 occurrence records. We estimated the position of each pixel predicted as presence in the ecological space using Euclidean distances. In short, we characterize all pixels for a single species and calculated which of these were close to the niche centroid (which we assume as the best conditions for species presence) and which were close to the niche periphery (see figure above). We predicted that pixels predicted by ENM as presences within each native island will be more close to the niche centroid and those predicted as presences in other islands will be in the periphery of the niche.

 

We found that many species follow the predicted pattern; in other words, we found that the “best” niche conditions are in the native island regardless of climatic heterogeneity observed in each island and the “worst” niche conditions are outside native islands. We also used other metrics to corroborate our results. We interpreted these results as  instances of recent climatic niche conservatism (within lineages) and therefore this operates as a constraint in the ability of each species to colonize other islands (i.e. due to the low suitable climatic conditions for successful population establishment). We only gathered data for 70 species and therefore it will be necessary more data and more studies (including physiological experiments) to corroborate our assertions.

Also, we examined the pattern of realized climatic niche shifts across the anole radiation and we found evidence of several instances of climatic niche convergence. We concluded that anoles evolved to occupy different portions of the climate space and in several cases evolved quickly to occupy some portions of this space (e.g., cold climatic conditions) and recently most of these species likely adapted very well to climatic conditions in their. native islands.

The paper was published in Evolutionary Biology.

 

 

 

 

My former postdoc advisor and AA co-founder Jonathan Losos recently reminded me that I left some unused samples in a drawer in the lab that he has now moved out of.

In 2012, I spent some time in Puerto Rico, collecting niche data for six anole species (A. cristatellus, A. evermanni, A. gundlachi, A. krugi, A. pulchellus and A. stratulus) among other things. I collected some samples for stomach content and stable isotope analysis that I never got around to processing before I moved on to the next postdoc. As I’m now based in New Zealand and back to working on fish, it’s not worth the complications of importing samples that I don’t have immediate plans to use.

At Jonathan’s suggestion, I am making the samples available to any anologists who can give them a good home. The data are unlikely to lead to anything groundbreaking, but could make for a nice integrated study of niche partitioning and could be a good student project for someone.

The samples contain:

• Stomach contents from at least 30 anoles of each of the six species, obtained via gastric lavage and stored in ethanol in eppendorf tubes.
• Tail tips taken for stable isotope analysis, dried and stored in eppendorf tubes.
• Dried tissue samples from herbivorous (katydids x 10) and detritivorous (land snails x 10) invertebrates to use as isotopic baselines.
• Additional pieces of the same tail tips, stored in ethanol in Eppendorf tubes, which could be used for genetics if needed.

The samples should still be in good shape, though they’ve spent the last six years boxed up in a drawer. All the anoles were released live, so I don’t have specimens. However, for each individual I have recorded:

• collection date, GPS location and elevation
• environmental temperature
• body (cloacal) temperature
• perch height and diameter
• body orientation and position in sun vs shade
• sex and SVL

The idea behind collecting these data was to quantify how much of the variation in different niche dimensions was attributable to differences between ecomorphs (trunk-crown, trunk-ground and grass-bush), between species (two species per ecomorph), and between sexes. I would be happy to donate the samples to someone who can make good use of them, or to collaborate with someone who would like to follow up on this small project idea.

If you are interested in taking over the samples, please get in touch with me in the next couple of weeks (after that they will likely be disposed of).

Travis (email)