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This guy was found in central Virginia, under a flower pot. He's about 3 inches long, because part of his tail is either missing or it's just short. He looked dried out, so of course I wet my hand, scooped him into a small container, and moved him to our birdbath (which is on the ground and had been recently rinsed so the ground was plenty moist). I ran my hand (still wet) over his back and he seemed happier and started moving around.
However, I can't seem to find on Google just what kind of salamander he is. The VA Herpetological Society has an entry for a Jefferson Salamander, but those are only found in North/West VA. Attached is a picture of him (blurry, sorry) when I found him. I have a video of him coming out of the container and going under the leaves next to the birdbath, but it's too big of a file to put on here. Instead, here is a link to the file in my Google Drive: Salamander
Edit: I checked some pictures I had of him, and he has five toes on his hind legs. He is a dark gray-brown with faint mottling and a semi-light underbelly. Sorry that I didn't say this earlier. Hope this helps!
Can anyone identify him?
Maybe it's a Mabee's Salamander, Ambystoma mabeei. Unfortunately, I can't really see the underside in your video, but I have the sense that it is a lighter color. The clubbed tail, with an apparent break, seems like it may have been autotomized or otherwise injured, making it harder to compare. I had the impression your example had dark spots dorsally and lightening ventrally, as can be seen in the image above. Some other images are a bit different. However, Mabee's Salamander is only found in "six localities in the coastal plain in extreme southeastern Virginia: the cities of Hampton and Suffolk and the counties of York, Southampton, Gloucester, and Isle of Wight. It is also found in Newport News." and is considered threatened, so unless your location matches what you read there it is still not likely to be the answer.
All The Single (Salamander) Ladies
A population of mole salamanders in the Midwest is throwing a curveball at our understanding of sex and reproduction. Some populations of this salamander are unisexual—they’re females that can reproduce without males.
The unisexual mole salamanders aren’t just cloning themselves, however. “These salamanders really are taking advantage of the system,” says Katy Greenwald, an associate professor of biology at Eastern Michigan University. “They’re all female, so they don’t bear that cost of producing males, but they’re occasionally incorporating DNA from other species. In some ways it seems like this potentially totally unique evolutionary win-win—which might ultimately let us learn a little more about the evolution and maintenance of sexual reproduction.”
These salamanders may not need males, but they do need sperm to reproduce. Various species of male salamanders leave packets of sperm lying around, and the mole salamander females steal them. This particular population of unisexual mole salamander can reproduce from five different salamander species that live nearby, and a single clutch of eggs could hold offspring with genetic ties to several different species.
Greenwald joins Ira to explain what advantages living a single-sex life may have for the mole salamander.
Missing Parts? Salamander Regeneration Secret Revealed
Salamanders can regrow entire limbs and regenerate parts of major organs, an ability that relies on their immune systems, research now shows.
A study of the axolotl (Ambystoma mexicanum), an aquatic salamander, reveals that immune cells called macrophages are critical in the early stages of regenerating lost limbs. Wiping out these cells permanently prevented regeneration and led to tissue scarring. The findings hint at possible strategies for tissue repair in humans.
"We can look to salamanders as a template of what perfect regeneration looks like," lead study author James Godwin said in a statement. "We need to know exactly what salamanders do and how they do it well, so we can reverse-engineer that into human therapies," added Goodwin, of the Australian Regenerative Medicine Institute (ARMI) at Monash University in Melbourne. [Ready for Med School? Test Your Body Smarts]
In mammals, macrophage cells play an important role in the immune system response to injury, arriving at a wound within two to four days. There, they engulf and digest pathogens, or infectious particles, and generate both inflammatory and anti-inflammatory signals for healing.
Now, Godwin and his colleagues have shown that macrophages are essential for salamanders' superherolike ability to sprout new limbs. The researchers studied the biochemical processes that occurred in salamanders at the site of a limb amputation. They then wiped out some or all of the macrophage cells to determine whether these cells were essential for regrowing the limbs.
Signals of inflammation were detected at the wound sites within one day of the amputations. Unexpectedly, anti-inflammatory signals, which normally arrive later in mammals recovering from injury, were also present at that time. Along with these signals, the researchers detected macrophages at the wound, peaking in number around four to six days after the injury.
To investigate the role of macrophages in salamander limb regeneration, the researchers injected the animals with a chemical substance that destroys or "depletes" these cells. The macrophage levels were either partially or fully depleted.
Salamanders that had all their macrophages removed failed to generate new limbs and showed substantial scar-tissue buildup. Salamanders that had only some of their macrophages could still regenerate their limbs, but more slowly than normal.
Once the salamanders replenished their macrophage levels, the researchers re-amputated the animals' limb stumps, which then fully regenerated at the normal rate. Collectively, these findings suggest macrophages are essential to the salamanders' remarkable wound-healing abilities.
Studying the regenerative abilities of salamanders could offer insight into treating spinal cord and brain injuries in humans, the researchers say. Furthermore, the knowledge might lead to new treatments for heart and liver diseases or recovery from surgery, by preventing harmful scarring.
Macrophages are already known to play a vital role in organ and tissue development in mouse embryos. They produce small signaling molecules that activate other types of cells that promote the growth of new limbs and the healing of wounds.
Many animals may have a capability for tissue regeneration that has been turned off as the result of evolution, but it might be possible to reactivate the process, Godwin said.
The findings were detailed today (May 20) in the journal Proceedings of the National Academy of Sciences.
Salamanders are typically more active during cool times of the day and are nocturnal. During the day they lounge under rocks or in trees to stay cool. At night they come out to eat.
Their bright, colorful skin warns predators to stay away, according to the San Diego Zoo. Many salamanders have glands on their necks or tails that secrete a bad-tasting or even poisonous liquid. Some can also protect themselves from predators by squeezing their muscles to make the needle-sharp tips of their ribs poke through their skin and into the enemy.
Some species can shed their tails during an attack and grow a new one. The axolotl, an aquatic salamander, can grow back limbs lost in fights with predators and damaged organs due to a special immune system.
Salamanders are carnivores, which means they eat meat instead of vegetation. They prefer other slow-moving prey, such as worms, slugs and snails. Some larger types eat fish, small crustaceans and insects. Some salamanders eat frogs, mice and even other salamanders.
Eurycea subfluvicola: New Species of Salamander Discovered in Arkansas
Ouachita Streambed Salamander (Eurycea subfluvicola). Image credit: Mike Steffen / University of Tulsa.
In May 2011, the team caught a single specimen of the new species while collecting larvae of a more common species, the Many-ribbed Salamander (Eurycea multiplicata).
“DNA analyses later revealed that this specimen was most closely related to, but still highly divergent from the many-ribbed salamander, and all other described salamanders,” explained Dr Ronald M. Bonett from the University of Tulsa, who is the senior author of the paper published in the journal Zootaxa (full paper in .pdf).
The new salamander species has been scientifically named Eurycea subfluvicola. The common name is the Ouachita Streambed Salamander.
“The name subfluvicoa (dwells below the streambed) describes the species’ behavior of retreating below the streambed when surface waters dry,” Dr Bonett said.
“In fact, due to severe drought conditions in the area, it was almost two years before additional specimens were located.”
With these additional specimens, Tulsa University PhD student Michael Steffen, fellow gradate student Andrea Blair, and Dr Bonett, showed that not only is the new species genetically distinct, but differs from the Many-ribbed Salamander in their shape and life history traits.
“The Ouachita Streambed Salamander is paedomorphic, meaning that it retains aquatic larval juvenile characteristics into adulthood, and therefore it superficially resembles the aquatic larvae of related species.”
Ouachita Streambed Salamander (Eurycea subfluvicola), female. Image credit: Steffen MA et al.
The Ouachita Streambed Salamander measures about 35-45 mm in males and 31-48 mm in females.
“The dorsum of the salamander is primarily uniform amber/yellow background color, pigmented with numerous dark brown melanophores, which create irregularly shaped blotches throughout the dorsum and flanks,” Dr Bonett and his colleagues wrote in the Zootaxa paper.
“In most individuals irregularly spaced spots are formed by the absence of melanophores along the dorsolateral region of the trunk, possibly indicative of the lateral line. The semi-transparent venter is unpigmented, except for a few widely dispersed melanophores beneath the tail. Dorsal and ventral coloration is separated by a sharply defined ventral-lateral boundary along the trunk.”
The Ouachita Streambed Salamander is only known from two nearby sites near Hot Springs: a 15-m section of Slunger Creek and a 50-m section of an unnamed tributary within the Slunger Creek alluvial valley, about 135 m apart from one another.
Dr Bonett added: “despite similar habitat nearby, and considerable searching effort, the Ouachita Streambed Salamander has only been found at two small stream sections, making it currently one of the most restricted known ranges for any amphibian species in the United States.”
“This is one of the most genetically distinct paedomorphic new species of salamander discovered in the United States within the past 70 years.”
“The study also shows how developmental shifts, such as larval paedomorphosis, can allow unrecognized species to hide amongst the larvae or juveniles of close relatives,” Dr Bonett said.
Steffen MA et al. 2014. Larval masquerade: a new species of paedomorphic salamander (Caudata: Plethodontidae: Eurycea) from the Ouachita Mountains of North America. Zootaxa 3786 (4): 423–442 doi: 10.11646/zootaxa.3786.4.2
How a female-only line of salamanders ‘steals’ genes from unsuspecting males
Kleptogenesis gets a little less mysterious in a new study.
Imagine a lineage made up solely of women. Generation after generation, these females pilfer genes from males—not mating and reproducing in the usual way, but using sex as a means to collect genetic material that they can parcel out to their offspring in seemingly any configuration. A few genes here, a few genes there, generation after generation. It’s not some Themyscira-esque fantasy: some lady salamanders have been carrying on this way for millions of years.
The strange reproductive behaviors of the genus Ambystoma aren’t new to science. Researchers have known for some time that one lineage of these animals—a line of salamanders that only ever have female offspring—persist by collecting the genetic material of males from several other species in the genus. But in case this is your first time encountering the fantastical world of “kleptogenesis” (side note: great word), here’s a run-down.
Many members of the salamander genus Ambystoma are sexual creatures—by which we mean males drop sperm packets to fertilize female eggs, producing offspring with a set of genetic instructions from each of their two parents. But unisexual Ambystoma lizards do it better. These females pick up those packets, but they can gather more than one with which to fertilize their eggs. And once they do, it seems to be up to them to decide which parts of the genome—if any—they use from each of their mates.
“Most vertebrates that reproduce in ways that involve only females end up being sperm-dependent in one way or another,” says Maurine Neiman, associate professor in biology at the University of Iowa. Many of those lineages become “sperm parasites”, requiring sperm to penetrate their eggs in order to trigger development into embryos. They need that sperm to get things going, but they throw the genetic material away—essentially creating clone daughters while obeying the reproductive mechanics developed by their sexually reproducing ancestors.
“Superficially, these salamanders seem to have a lot in common with those other females,” Neiman says. But in fact, their “bizarre” method of reproduction has never been documented in another animal. And it’s kept them alive for much longer than other methods of makeshift asexual reproduction.
“They have the same dependence on sperm, but they also keep the genomes—or some of them, anyway—of the males they mate with,” she explains.
The female salamanders seem to be able to dole out genes to their daughters in all sorts of configurations. Individuals are basically salamander hybrids made up of the DNA of a variety of species, unified by common mitochondrial DNA (which a mother passes directly to her children, with no male input) from an ancient ancestor. Some carry five unique genomes around in the nuclei of their cells. They appear to always carry at least one copy of the A. laterale genome (the blue-spotted salamander), even though this species doesn’t seem to be the one from which they all descend. Scientists still don’t know how a salamander “chooses” what genes to give her daughter, but they know that mom can basically make whatever kind of Franken-mander she desires.
“Let’s say she’s got three copies of a genome,” Neiman explains—plus one she was born with. “She might not incorporate any of the surplus genes [into her babies]. She might incorporate one of their genomes along with her own. She might give them all three plus her own, so her baby has four. Or she could even leave out the one she was born with and pass along the other three.”
In a study published recently in Genome Biology and Evolution, Neiman and her colleagues at the University of Iowa and The Ohio State University—led by a graduate student from each lab—tried to puzzle out what the heck a salamander does when spoiled for gene choice. And they were fueled by more than just herpetological curiosity.
“We’re interested in the broader question of why genomes are organized as they are in most animals,” she says. “We typically have two copies. Why is that? We don’t have a good understanding of that. And in biology, one way to get at a question is to look at something weird. You can sometimes understand the typical by figuring out how the exception to the rule works.”
The little lady her team studied was definitely an exception to the rule: she carried three genomes, making her a “triploid” organism. Analysis of her DNA revealed that most of the genes taken from males of other species—Ambystoma laterale, Ambystoma texanum, and Ambystoma tigrinum—had been expressed equally. Genes make us who we are by instructing our cells to make certain proteins at certain times, contributing to specific bodily structures and processes. We say a gene is “expressed” when it’s allowed to do the thing it’s meant to do, leading to some physical result. If you’ve got multiple genomes kicking around, you probably have genes that don’t need to be turned on—they might be duplicates of a gene from another source, or even produce proteins that conflict with those made by different genes. According to the new study, while a salamander seems to pass her ill-begotten genes down in all manner of assorted mixtures, her daughter is likely to use the resulting genomes pretty equally to dictate her bodily functions. That’s unusual in the world of hybrids.
“That surprised us,” Neiman says. “When you have hybrids, you usually think one genome is going to be used preferentially while the other is shut down. But these questions are typically asked in the context of plant hybrids.” Many of the crops we grow today have been hybridized so much throughout their evolutionary history that they now carry many genomes wheat has six copies of each of its seven chromosomes. Scientists know an awful lot more about plant hybrids than strange critters like these salamanders, Neiman says, but it’s possible that a better understanding of how the extreme gene swapping works could help us breed better crops in the future.
“You start to wonder if this ability to have so much genomic flexibility set them up to be able to use their bizarre method of reproduction,” she says. “Does this mean that in general, animals are more flexible about genome use than plants?” Answering that question could help us understand more about how the two kingdoms evolved.
It could be that this balance is key to keeping the (kind of absurd) method of procreation going. “If you have a team that’s unbalanced and loses a top player, you won’t win,” Kyle McElroy, a graduate student in Neiman’s lab and the paper’s corresponding author, said in a statement. “But if every player is equal, then you don’t lose as much.”
Neiman and her colleagues can’t be sure whether the genome equality persists as things get more crowded. The follow-up study that’s “just crying out to be done,” Neiman says, would be to examine a salamander with even more genomes—some females are born carrying a genome from five different species of Ambystoma. More study is definitely needed to suss out these strange salamanders.
The promiscuity of Ambystoma can be hard to wrap your head around if you think of species in the way most of us learn about them in school: individuals that can reproduce with one another. Hybrids like the unisexual members of Ambystoma muck that all up: they actually need to mate with multiple species in order to avoid extinction. And far from being sterile mules, their daughters continue to exhibit the incredible ability to steal and reconfigure genes for generation after generation. But Neiman says that the creatures are just one example of how fluid biology truly is.
“You’re talking to an evolutionary biologist who thinks a lot of the talk about speciation is just hype,” she says. “We’re humans, we like to put things in categories. But I’m not crazy about the idea that species are concrete in biology, outside of human context. Defining a species is useful in terms of research, but I’d say these salamanders demonstrate the messiness of biology and evolution—the fascinating and complicated reality that remains when you take the human need to put things into neat categories out of the picture.”
Rachel Feltmanis the Executive Editor of Popular Science and the host of the podcast The Weirdest Thing I Learned This Week. She's an alum of Simon's Rock and NYU's Science, Health, and Environmental Reporting program. Rachel previously worked at Quartz and The Washington Post. Contact the author here.
Undergraduate Research at UK with Gareth Voss (Part 1)
As a Paul Laurence Dunbar High School student, Gareth ("Gary") Voss came to the University of Kentucky to do research on the regenerative abilities of salamanders in Dr. Randal Voss's lab. Gary says, "At Dunbar in the Math-Science program, we have to join a faculty member at UK for a research project by the beginning of our junior year. And I heard about a professor at UK, who shared the same last name and the same first name, more or less, as my dad and his name is Randall Voss and he studies salamanders and regeneration.Things kind of clicked and I’ve been there ever since."
Gary's high-school project focused on tail regeneration. He notes, "I was not allowed to do any of the surgeries to remove the tails, but I was able to do the data analysis on the tails, and do a lot of interesting things in studying the regeneration of the salamanders."
Gary is now a freshman at UK majoring in biology and chemistry, and he says getting started early in research is really an advantage. "Getting started early gets you exposed to all the things you need to know. I was exposed to more things in genetics than most people my age would have been. Working in the lab not only puts you on the cutting edge of research and science, but it also lets you see all the things your classes are talking about in person, and to a greater extent."
Produced by Alicia P. Gregory (Research Communications), videography/direction by Chad Rumford (Research Communications)
For more information on Dr. Voss' lab, please visit ambystoma.org/
This video appears courtesy of Reveal: University of Kentucky Research Media research.uky.edu/reveal/index.shtml
They emerge from their subterranean hiding spots only at night to feed and during spring mating. They will actually travel long distances over land after a heavy rain to mate and lay their eggs in vernal pools and ponds.
Visually striking, these stout salamanders are bluish-black with two irregular rows of yellow or orange spots extending from head to tail. Like many other salamanders, they secrete a noxious, milky toxin from glands on their backs and tails to dissuade predators. Their diet includes insects, worms, slugs, spiders, and millipedes.
Salamanders, Regenerative Wonders, Heal Like Mammals, People
The salamander is a superhero of regeneration, able to replace lost limbs, damaged lungs, sliced spinal cord -- even bits of lopped-off brain.
But it turns out that remarkable ability isn't so mysterious after all -- suggesting that researchers could learn how to replicate it in people.
Scientists had long credited the diminutive amphibious creature's outsized capabilities to "pluripotent" cells that, like human embryonic stem cells, have the uncanny ability to morph into whatever appendage, organ or tissue happens to be needed or due for a replacement.
But in a paper set to appear July 2 in the journal Nature, a team of seven researchers, including a University of Florida zoologist, debunks that notion. Based on experiments on genetically modified axolotl salamanders, the researchers show that cells from the salamander's different tissues retain the "memory" of those tissues when they regenerate, contributing with few exceptions only to the same type of tissue from whence they came.
Standard mammal stem cells operate the same way, albeit with far less dramatic results -- they can heal wounds or knit bone together, but not regenerate a limb or rebuild a spinal cord. What's exciting about the new findings is they suggest that harnessing the salamander's regenerative wonders is at least within the realm of possibility for human medical science.
"I think it's more mammal-like than was ever expected," said Malcolm Maden, a professor of biology, member of the UF Genetics Institute, and author of the paper. "It gives you more hope for being able to someday regenerate individual tissues in people."
Also, the salamanders heal perfectly, without any scars whatsoever, another ability people would like to learn how to mimic, Maden said.
Axolotl salamanders, originally native to only one lake in central Mexico, are evolutionary oddities that become sexually reproducing adults while still in their larval stage. They are useful scientific models for studying regeneration because, unlike other salamanders, they can be bred in captivity and have large embryos that are easy to work on.
When an axolotl loses, for example, a leg, a small bump forms over the injury called a blastema. It takes only about three weeks for this blastema to transform into a new, fully functioning replacement leg -- not long considering the animals can live 12 or more years.
The cells within the blastema appear embryonic-like and originate from all tissues around the injury, including the cartilage, skin and muscle. As a result, scientists had long believed these cells were pluripotential -- meaning they came from a variety of sites and could make a variety of things once functioning in their regenerative mode.
Maden and his colleagues at two German institutions tested that assumption using a tool from the transgenic kit: the GFP protein. When produced by genetically modified cells, GFP proteins have the useful quality of glowing livid green under ultraviolet light. This allows researchers to follow the origin, movement and destination of the genetically modified cells.
The researchers experimented on both adult and embryonic salamanders.
With the embryos, the scientists grafted transgenic tissue onto sites already known to develop into certain body parts, then observed how and where the cells organized themselves as the embryo developed. This approach allowed them to see, literally, what tissues the transgenic tissue made. In perhaps the most vivid result, the researchers grafted GFP-modified nerve cells onto the part of the embryo known to develop into the nervous system. Once the creatures developed, ultraviolet light exams of the adults revealed the GFP cells stretched only along nerve pathways -- like glowing green strings throughout the body
With the adults, they took tissue from specific parts or organs from transgenic GFP-producing axolotls, grafted it onto normal axolotls, then cut away a chunk of the grafted tissue to allow regeneration. They could then determine the fate of the grafted green cells in the emerging blastema and replacement tissue.
The researchers' main conclusion: Only 'old' muscle cells make 'new' muscle cells, only old skin cells make new skin cells, only old nerve cells make new nerve cells, and so on. The only hint that the axolotl cells could revamp their function came with skin and cartilage cells, which in some circumstances seemed to swap roles, Maden said.
Maden said the findings will help researchers zero in on why salamander cells are capable of such remarkable regeneration. "If you can understand how they regenerate, then you ought to be able to understand why mammals don't regenerate," he said.
Maden said UF researchers will soon begin raising and experimenting on transgenic axolotls at UF as part of the The Regeneration Project, an effort to treat human brain and other diseases by examining regeneration in salamanders, newts, starfish and flatworms.
Materials provided by University of Florida. Note: Content may be edited for style and length.
IU News Room
FOR IMMEDIATE RELEASE
April 4, 2011
BLOOMINGTON, Ind. -- A species of algae long known to associate with spotted salamanders has been discovered to live inside the cells of developing embryos, say scientists from the U.S. and Canada, who report their findings in this week's Proceedings of the National Academy of Sciences.
Photo courtesy of Roger Hangarter
Salamander embryos grow inside egg capsules that are covered with and usually infiltrated by a type of green algae
This is the first known example of a eukaryotic algae living stably inside the cells of any vertebrate.
"It raises the possibility that more animal/algae symbioses exist that we are not aware of," said Indiana University Bloomington biologist Roger Hangarter, the PNAS report's sole American coauthor. "Since other salamanders and some frog species have similar algae/egg symbioses, it is possible that some of those will also have the type of endosymbioses we have seen in the spotted salamander."
Biologists Ryan Kerney, Eunsoo Kim, Aaron Heiss, and Brian Hall of Dalhousie University in Halifax, Nova Scotia, and Cory Bishop of St. Frances Xavier University in Antigonish, Nova Scotia, are the other members of the research team. Kerney was the report's lead author.
"We were particularly excited to discover this association in spotted salamander embryos, because this species was a model organism for early experimental embryology research and is a locally common salamander in eastern North America," Kerney said. "We hope that this study will highlight biodiversity research on common North American species, which can easily be overlooked or even considered over-studied."
Vertebrates are backboned animals. The group includes amphibians like the spotted salamander, as well as mammals, birds and reptiles. The rarity of vertebrate endosymbiosis, as the cell-within-a-cell association is called, has been thought to be the result of the animals' stringently xenophobic immune systems. Any foreign cell that manages to get as far as breaching a cell membrane normally triggers a number of slay-now-and-ask-questions-later gene systems.
Naturalists first noticed an association between spotted salamander eggs and green algae more than 100 years ago. This relationship was formalized by name in 1927 by Lambert Printz, who named the algal species Oophilia amblystoma. The genus name means "egg loving." The nature of that symbiosis was not known until the 1980s, when experimentation revealed the salamander embryos do not develop as quickly or as fully in the absence of the green algae. Likewise, algae grown separately from the embryos but in the presence of water exposed to the embryos also grew more robustly.
Despite decades of study, the revelation of an endosymbiosis between the amphibian and alga took many by surprise when Kereny presented preliminary information at a scientific meeting last year. The reason, Hangarter said, is that the algae cells were not easy to see by conventional light microscopy. Because the chlorophyll in the algae is highly fluorescent, the scientists were able to use modern fluorescent microscopy to probe to the salamanders.
They also used a short string of nucleic acids that targets and binds to a ribosomal RNA molecule unique to Oophilia (18S rRNA) and by a visualization technique called fluorescence in situ hybridization, they found that the algae RNA is pervasive within spotted salamander embryo cells.
Photo courtesy of Roger Hangarter
Spotted salamanders are the first known vertebrate to have an endosymbiont. The salamanders are found throughout eastern North America.
"With the ability to use gene-specific probes, it is now possible to determine the presence of organisms that may not be easily visible by standard light microscopy," Hangarter said. "In the past, researchers looking with simpler light microscopy techniques than are available today failed to see any algae in the salamanders."
The symbiotic relationship between spotted salamanders and Oophilia is mutualistic because both creatures benefit. Symbiosis is a general category of species-species interaction in which the organisms share space for extended periods of time. Symbioses can benefit one organism and harm the other (parasitism), benefit both (mutualism), or benefit one creature and leave the other unaffected (commensalism).
Endosymbiosis is a special type of symbiosis, requiring one organism to live inside the cells of another. It is not yet known how the endosymbiotic infiltration of salamander embryo cells affects either the salamander or the alga. Anything is possible, despite the fact that the overall relationship between the two species is established as mutualistically beneficial.
Endosymbiosis also has special evolutionary significance, as it is presumed by biologists to have preceded the full integration of certain cell organelles, such as mitochondria and chloroplasts, special structures that perform unique functions within cells -- and possess their own chromosomes.
Kerney and Hangarter say they hope their ongoing work will inspire interest in local biology and respect for environmental protection.
"We would like this work to draw attention to a fascinating yet common backyard salamander, and hope that it will both raise awareness of the species and promote the preservation of their fragile breeding habitat," Kerney said.
Hangarter agreed, adding, "I think it is important for people to realize that you do not need to go to exotic locations to make interesting scientific discoveries. The vernal ponds that the salamanders mate in are also essential for many other amphibians and other organisms, but such ponds are often among the first things destroyed when humans develop in wooded areas. One 500 square-foot pond might service several thousand mating salamanders and frogs that might inhabit an area of a few acres of woodland."
This research was supported by grants from the National Science Foundation, Tula Foundation (Canada), the Natural Sciences and Engineering Research Council of Canada, and the American Association of Anatomists.
Video of the salamanders can be obtained from the PNAS News Office: [email protected] or 202-334-1310.
A movie that Hangarter and documentarian Samuel Orr created about spotted salamanders for WFYI (PBS affiliate, Indianapolis) can be viewed on the Web at https://www.booglehouse.com/wfyi/NHI/gallery/mediaGallery.html (select "2. Life in the Water" and then "Spotted Salamanders").
To speak with Hangarter, please contact David Bricker, University Communications, at 812-856-9035 or [email protected] . To speak with Dalhousie University biologists Ryan Kerney or Brian Hall, please contact Charles Crosby at [email protected] or 902-494-1269.
"Intracellular invasion of green algae in a salamander host," Proceedings of the National Academy of Sciences, v. 108 iss. 14 (pub. April 4)