Mandica M.,Atlanta Botanical Garden |
Hu D.L.,Georgia Institute of Technology
Journal of the Royal Society Interface | Year: 2017
Frogs can capture insects, mice and even birds using only their tongue, with a speed and versatility unmatched in the world of synthetic materials. How can the frog tongue be so sticky? In this combined experimental and theoretical study, we perform a series of high-speed films, material tests on the tongue, and rheological tests of the frog saliva. We show that the tongue's unique stickiness results from a combination of a soft, viscoelastic tongue coupled with non-Newtonian saliva. The tongue acts like a car's shock absorber during insect capture, absorbing energy and so preventing separation from the insect. The shear-thinning saliva spreads over the insect during impact, grips it firmly during tongue retraction, and slides off during swallowing. This combination of properties gives the tongue 50 times greater work of adhesion than known synthetic polymer materials such as the sticky-hand toy. These principles may inspire the design of reversible adhesives for high-speed application. © 2017 The Author(s) Published by the Royal Society. All rights reserved.
Johnson T.,Georgia Institute of Technology |
Cruse-Sanders J.M.,Atlanta Botanical Garden |
Pullman G.S.,Georgia Institute of Technology |
Pullman G.S.,Institute of Paper Science And Technology
In Vitro Cellular and Developmental Biology - Plant | Year: 2012
Xyris tennesseensis is a critically endangered species native to the southeastern USA. A micropropagation protocol was developed which may assist in the safeguarding and augmentation of dwindling natural populations of this ecologically and medically valuable plant. Four different batches of seeds were sterilized using hydrogen peroxide and germinated in vitro on modified one third-strength Murashige and Skoog medium. Shoot multiplication from seedling tissue was obtained using modified one third-strength Murashige and Skoog medium containing 1 mg/l kinetin and 0. 1-0. 5 mg/l α-naphthaleneacetic acid. Optimal shoot size and sustainable multiplication rates of three to five per 2-mo subculture occurred on medium containing 0. 3-0. 4 mg/l α-naphthaleneacetic acid. Shoots rooted successfully when placed on growth regulator-free medium for 10 d followed by transfer to greenhouse soil under high humidity. Use of seed cryopreservation resulted in significant increases in germination compared to control treatments with average germination rates of 97%. Shoot tip cultures from soil-grown plants of X. tennesseensis and Xyris spathifolia were also developed using the above protocols. Plant tissue culture tools will assist in the multiplication, long-term storage, and conservation of these rare and valuable plants as well as provide a template for the micropropagation of other Xyris species. © 2012 The Society for In Vitro Biology.
Cruse-Sanders J.M.,Atlanta Botanical Garden |
Parker K.C.,University of Georgia |
Friar E.A.,500 N College Ave |
Friar E.A.,National Science Foundation |
And 5 more authors.
Ecology and Evolution | Year: 2013
Microsatellite markers (N = 5) were developed for analysis of genetic variation in 15 populations of the columnar cactus Stenocereus stellatus, managed under traditional agriculture practices in central Mexico. Microsatellite diversity was analyzed within and among populations, between geographic regions, and among population management types to provide detailed insight into historical gene flow rates and population dynamics associated with domestication. Our results corroborate a greater diversity in populations managed by farmers compared with wild ones (HE = 0.64 vs. 0.55), but with regional variation between populations among regions. Although farmers propagated S. stellatus vegetatively in home gardens to diversify their stock, asexual recruitment also occurred naturally in populations where more marginal conditions have limited sexual recruitment, resulting in lower genetic diversity. Therefore, a clear-cut relationship between the occurrence of asexual recruitment and genetic diversity was not evident. Two managed populations adjacent to towns were identified as major sources of gene movement in each sampled region, with significant migration to distant as well as nearby populations. Coupled with the absence of significant bottlenecks, this suggests a mechanism for promoting genetic diversity in managed populations through long distance gene exchange. Cultivation of S. stellatus in close proximity to wild populations has led to complex patterns of genetic variation across the landscape that reflects the interaction of natural and cultural processes. As molecular markers become available for nontraditional crops and novel analysis techniques allow us to detect and evaluate patterns of genetic diversity, genetic studies provide valuable insights into managing crop genetic resources into the future against a backdrop of global change. Traditional agriculture systems play an important role in maintaining genetic diversity for plant species. © 2013 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.
News Article | October 27, 2016
On 26 September, staff with the Atlanta Botanical Garden found a frog dead in his enclosure. The frog had big brown eyes, massive feet with thick webs between the toes, and brownish skin speckled with little yellow dots. His name was Toughie. He was big for a frog and he didn’t like it when humans handled him. He’d lived a long time: 12 years. And he was the last of his kind. On 26 September 2016, the world very likely lost Rabbs’ fringe-limbed treefrog (Ecnomiohyla rabborum) to extinction. The species, only discovered by scientists in 2005, lived in Panama before it was wiped out in the wild by habitat destruction and the amphibian disease, chytridiomycosis. The last one was heard calling in the wild in 2007. But before this, a small number of Rabbs’ fringe-limbed treefrog had been taken into zoological facilities for captive breeding. Unfortunately, the attempt failed. Toughie was the last to die. Despite the fact that we can actually trace the extinction of Rabbs’ fringe-limbed treefrog to an exact date, it occurred with very little media interest. Sure, the species’ demise was covered by many standard science media sites, such as Scientific American, National Geographic, and Mongabay. But the list of what media outlets thought the story not interesting enough is perhaps more notable, including the BBC, the Sun, and CNN. Even this outlet, the Guardian, did not devote a full article to the extinction. Many news sites simply reprinted the Associated Press’s story, which spilled 264 words on the extinction of Rabbs’ fringe-limbed treefrog (in contrast, the AP wrote three times as many words, 798, on Taylor Swift’s concert at Formula One). The New York Times at first only carried the AP article, though it later published a beautiful op-ed by one of the researchers. Still, I waited a little while to see if news coverage would pick up as the story trickled out – it didn’t. A week after the extinction, I gave a presentation to a local herpetological society, ie devoted to amphibians and reptiles. When I brought up the recent demise of Rabbs’ fringe-limbed treefrog, there were audible gasps in the room. Even herp lovers hadn’t heard of it. This begs the question: how could the public care about global mass extinction if they aren’t even told about its victims? How can we care if we don’t grieve? Scientists have repeatedly warned that if we don’t change our ways we could see a mass extinction event with potentially hundreds of thousands, even millions, of species wiped out by human actions. The impact – and scale – is impossible to imagine. The last time the Earth suffered such a mass extinction event was when an asteroid slammed into it, killing off all the non-avian dinosaurs. We didn’t show up for another 64m years. Despite this, most media outlets chose to ignore a story that could not only inform readers of the loss of one distinct species, but also connect them to a global crisis that rarely makes its way on to the front page – or any page for that matter. I don’t know why so many outlets ignored the story – but it may be because the species that went extinct was a frog and not a big mammal like the baiji (which also didn’t get the coverage it deserved when it vanished, but got plenty more than Toughie’s species). Still, Rabbs’ fringe-limbed treefrog was truly amazing. Living in the canopies of Panama’s cloud forests, this species glided through the air via the webbing connecting it toes. Scientists also believe that it was the only frog species to feed its tadpoles by allowing them to nibble at the skin of adults. If a frog such as this is not noteworthy, what does that mean for the reptiles, fungi, plants, insects or fish that vanish? What does that say about any species that doesn’t grip the public’s imagination – are they somehow lesser for not having evolved (or vice versa) to be easily loved by us? Amphibians are the canary in the coalmine for our current biodiversity crisis. Having been around for 370m years, amphibians make dinosaurs look babyish. But experts believe we may have lost more than 150 species in the last few decades alone, many of them to chytridiomycosis. On top of this amphibian plague, amphibians are being hard hit by deforestation, habitat loss, pollution, pesticides, the illegal wildlife trade for pets and even consumption and yes, of course, climate change (which may be exacerbating the stunning death tolls of chytridiomycosis). Unfortunately, Toughie will not be the last frog to vanish or the last species. How many more will depend on us. But it’s hard to imagine anything changing when a story like Toughie’s is so easily swept aside. We can’t care about what we don’t know.
News Article | November 11, 2016
Ticket Alternative, a boutique ticketing, event registration and technology company, has officially launched its Freshtix “Daily Admission” model. The new model allows clients to feature events with multiple dates and entry times on a stand-alone, fully customized web site. This differs from the standard Freshtix model (called the Multi-tenant solution launched in 2014) where Organizers manage and promote their events along many other Organizers on the web site Freshtix.com. Freshtix co-founder, Iain Bluett, says of the new model, “By offering two versions of Freshtix, we can compete with both the do-it-yourself solutions and the antiquated ticketing systems used for attractions, botanical gardens, museums and zoos. With the Daily Admission model, we’re making ticketing, managing memberships and attending these types of events easier for our clients and their patrons.” Most recently, Freshtix partnered with Callanwolde Fine Arts Center to launch the Daily Admission Model for their annual Christmas tour, along with their new “Christmas at Callanwolde Light Show,” presented by Illuminating Design. (http://callanwolde.freshtix.com) Freshtix worked with the Callanwolde team to launch a fully branded eCommerce ticketing site, capable of managing hundreds of unique event occurrences, in under a month. The site uses many of the same features Freshtix first Daily Admission model client (Atlanta Botanical Garden) enjoyed, specifically the “Member Match” functionality. Callanwolde Fine Arts Center members are recognized on the web site site by their email address and/or member number and immediatelty offered discounted tickets as part of the membership package. Non-members are encouraged to become members by learning of the benefits and discounts of membership during the check out process. “With multiple events every day, it was important for us to find a ticketing solution that could handle our unique ticketing needs while recognizing our important members. The Freshtix platform is robust but incredibly user-friendly. I can add a new event in less than a minute not to mention the aesthetics of our branded site, which we couldn’t have been more pleased with,” says Peggy Still Johnson, Executive Director. Looking forward, Ticket Alternative will continue to grow both versions of its Freshtix platform for general admission events while leveraging it’s legacy ticketing platform (powered by Spectra) for events with reserved seating, with the ultimate goal of providing clients multiple customizable options when deciding how to ticket their events. For more information on the Daily Admission model or becoming a Freshtix organizer, contact Jesi Bullrich, Strategic Enhancement Consultant, via email: jesi.bullrich(at)ticketalternative(dot)com
News Article | September 28, 2016
The world’s last known Rabbs’ fringe-limbed tree frog (Ecnomiohyla rabborum) has died. Known as “Toughie,” the tiny male frog, originally from Panama, spent the past few years living by himself at Atlanta Botanical Garden. The species has not been observed in the wild since 2007, just two years after it was first discovered by scientists. Toughie’s death follows four and a half years after another Rabbs’ tree frog died at Zoo Atlanta. That frog was euthanized in 2012 after its health began to decline. Both of these Rabbs’ tree frogs were collected in Panama while scientists were there investigating the deadly chytrid fungus, which has devastated amphibian populations in that country and around the world. Although no signs of wild Rabbs’ tree frogs have shown up in the past nine years, at least one scientist still held out hope they might one day be found again. “The habits of this genus can make them extremely difficult to find if they remain high up in the trees,” says Jonathan Kolby, director of the Honduras Amphibian Rescue and Conservation Center. “Being that this species breeds in tree cavities up in the canopy, I would hope that this behavior offers some protection from exposure to chytrid fungus, although the species was reported to have become much less common after the arrival of chytrid in the region.” Still, the likelihood remains that the Rabbs’ fringe-limbed tree frog is now truly gone. That’s notable, not just for the extinction, but for the circumstances around Toughie’s life. Extinctions, you see, are very rarely witnessed by humans. Instead, they tend to be discovered years or even decades after the last member of a species gave up the fight. The Rabbs’ tree frog was a rare exception. For the past four and a half years, Toughie has been a very public ambassador for his lost species, and for all of the frog species going extinct around the world during the current amphibian extinction crisis. How many thousands of people who walked by his enclosure at Atlanta Botanical Garden felt the pull and gravity of his inevitable extinction? As the organization posted today on Facebook, “He will be missed by Garden staff and visitors alike.”
PubMed | Texas Tech University and Atlanta Botanical Garden
Type: Journal Article | Journal: Genetica | Year: 2016
We investigated the patterns of genetic diversity and structure in seven disjunct populations of a rare North American orchid, Cypripedium kentuckiense by including populations that represented the periphery and the center of the its range. Eight nuclear and two chloroplast microsatellites were used. Genetic diversity was low across the sampled populations of C. kentuckiense based on both nuclear (average An=4.0, Ho=0.436, He=0.448) and cpDNA microsatellites (average An=1.57, Nh=1.57 and H=0.133). The number of private alleles ranged from one to four per population with a total of 17 private alleles detected at five nuclear microsatellites. One private allele at one cpDNA microsatellite was also observed. Although the absolute values for nuclear microsatellite based population differentiation were low (Fst=0.075; PT=0.24), they were statistically significant. Pairwise Fst values ranged from 0.038 to 0.123 and each comparison was significant. We also detected isolation by distance with nDNA microsatellites based on the Mantel test (r(2)=0.209, P=0.05). STRUCTURE analysis and the neighbor joining trees grouped the populations similarly whereby the geographically proximal populations were genetically similar. Our data indicate that the species is genetically depauperate but the diversity is distributed more or less equally across its range. Population differentiation and isolation by distance were detectable, which indicates that genetic isolation is beginning to manifest itself across the range in this rare species.
Rogers W.L.,University of Georgia |
Cruse-Sanders J.M.,Atlanta Botanical Garden |
Determann R.,Atlanta Botanical Garden |
Malmberg R.L.,University of Georgia
Conservation Genetics Resources | Year: 2010
Sarracenia species (pitcher plants) are carnivorous plants which obtain a portion of their nutrients from insects captured in the pitchers. Sarracenia species naturally hybridize with each other, and hybrid swarms have been identified. A number of the taxa within the genus are considered endangered. In order to facilitate evolutionary, ecological and conservation genetic analyses within the genus, we developed 25 microsatellite loci which show variability either within species or between species. Three S. purpurea populations were examined with 10 primer sets which showed within population variability. © Springer Science+Business Media B.V. 2010.
Stephens J.D.,University of Georgia |
Rogers W.L.,University of Georgia |
Heyduk K.,University of Georgia |
Cruse-Sanders J.M.,Atlanta Botanical Garden |
And 3 more authors.
Molecular Phylogenetics and Evolution | Year: 2015
The North American carnivorous pitcher plant genus Sarracenia (Sarraceniaceae) is a relatively young clade (<3 million years ago) displaying a wide range of morphological diversity in complex trapping structures. This recently radiated group is a promising system to examine the structural evolution and diversification of carnivorous plants; however, little is known regarding evolutionary relationships within the genus. Previous attempts at resolving the phylogeny have been unsuccessful, most likely due to few parsimony-informative sites compounded by incomplete lineage sorting. Here, we applied a target enrichment approach using multiple accessions to assess the relationships of Sarracenia species. This resulted in 199 nuclear genes from 75 accessions covering the putative 8-11 species and 8 subspecies/varieties. In addition, we recovered 42. kb of plastome sequence from each accession to estimate a cpDNA-derived phylogeny. Unsurprisingly, the cpDNA had few parsimony-informative sites (0.5%) and provided little information on species relationships. In contrast, use of the targeted nuclear loci in concatenation and coalescent frameworks elucidated many relationships within Sarracenia even with high heterogeneity among gene trees. Results were largely consistent for both concatenation and coalescent approaches. The only major disagreement was with the placement of the purpurea complex. Moreover, results suggest an Appalachian massif biogeographic origin of the genus. Overall, this study highlights the utility of target enrichment using multiple accessions to resolve relationships in recently radiated taxa. © 2015 Elsevier Inc.
News Article | October 3, 2016
A rare species of tree frog may now be extinct following the death of its last known living member that lived in captivity. The frog called Toughie died in its enclosure at the Atlanta Botanical Garden. The male amphibian, which is believed to be about 12 years old, was found dead during a routine daily inspection conducted on Sept. 29. "It's a sad day here at the Garden as we mourn the loss of our beloved Rabbs' fringe-limbed tree frog, " the Atlanta Botanical Garden posted on its Facebook page. "He will be missed by Garden staff and visitors alike." Members of Toughie's species were graceful gliders and incredible climbers that can soar from one tree to another by toe webbing. In 2005, a team of scientists collected live animals in Panama as a deadly chytrid disease, an infectious disease in amphibians, threatened species in Central Panama. Scientists compared the effort to rescuing things from a burning house. The scientist brought back to Atlanta a new species of tree frog (Ecnomiohyla rabborum), the Rabbs' fringe-limbed tree frog. The disease eventually struck Panama, resulting in the disappearance of many frogs. Field studies suggest that up to 85 percent of the amphibians found on Toughie's home turf were gone. It is likewise unlikely that any of his kind survived in the wild. Toughie was found in 2005 but it was not until 2008 that his own species, was described. "Science had a very short window to learn about the species in the wild before this disease struck the only known locality for the frog and the species vanished," said Atlanta Botanical Garden President Mary Pat Matheson. In 2008, the Garden bought a climate-controlled facility called the Frog Pod to house the Rabbs' tree frog and other rare amphibians, where they can be completely isolated from each other. This is the facility where Tougie spent the last eight years of its life. The loss of Toughie and his species is tragic, but other amphibian species are also at risk of getting wiped out. Scientists estimate that up to one-half of amphibian species all over the world are at risk of extinction. "A lot of attention had been paid to him in captivity, so he even has his own Wikipedia page," said Amphibian Foundation Head Mark Mandica, who worked with Toughie for seven years. "But there are plenty of other species out there that are disappearing, sometimes before we even knew that they were there." © 2017 Tech Times, All rights reserved. Do not reproduce without permission.