This is just a quick post to announce that the first lungless frog has been discovered in Indonesia. Lungless salamanders and caecilians are well known, but no other lungless tetrapod has ever been described. Amphibians accomplish a lot of gas exchange over their skin. Being ectothermic, their rate of oxygen consumption is lower than ours, and being small, their surface-to-volume ratio is relatively high. All of those factors, combined with life in cold, fast-flowing streams where the water holds lots of oxygen, makes lunglessness an feasible adaptation. Still, it’s not very often that a species loses an entire major organ… how many vertebrates do you know with no heart or no brain? Okay, other than Dick Cheney and George W. Bush.

It just goes to show how many weird creatures are still out there, unknown to science. Like many amphibians, Barbourula kalimantanensis is threatened by anthropogenic factors, including habitat destruction and climate change. We are destroying things even before we know they exist.

(By the way, people have complained about my obscure titles in the past. Google them, people. It’s not that hard).

Good heavens, it appears we have neglected this site, haven’t we? The demands of grad school are taking their toll, I suppose. Well, this story is too good to pass up, and anyway it’s already written for me. Here’s a salamander-related adventure Ivan and Jacob had recently that made it onto the local news:

http://www.kcby.com/news/16317266.html

I have just returned from two weeks in Costa Rica, one of the world’s greatest hotspots of biodiversity. The purpose of my trip was religious, not scientific; I was chaperoning a group of 23 Unitarian Universalist teenagers on a mission of volunteer service. You can read about the social justice aspects of our adventure at the official ¡UURica! website. Here, I’d like to describe some of the amazing creatures I observed.

Costa Rica is teeming with animals; even though we weren’t there primarily to watch wildlife, I was constantly finding new species. A partial list includes: (mammals) spider monkeys, black howler monkeys, a neotropical river otter, a manatee, three-toed sloths, two-toed sloths; (reptiles) american crocodiles, spectacled caimans, basilisks, geckos, anoles, ameivas, green sea turtles; (amphibians) strawberry poison dart frogs, Stejneger’s rain frog and other leptodactylid frogs, southern roundgland toads, cane toads; (birds) roseate spoonbills, three species of toucans, anis, parrots, oropendulas, kiskidees, woodpeckers, kingfishers, a bat falcon, black vultures, jacanas, a frigatebird, egrets, herons, wood rails, anhingas, and many others; (invertebrates) heliconia butterflies, blue morpho butterflies, land crabs, tarantulas, and many many others… etc… To illustrate the intimate nature of some of these encounters, here are three examples:

Cane toad (Bufo marinus). Cane toads are probably best known as ruthless invaders that are taking over Australia and other Pacific islands. They eat anything they can fit in their mouths, they secrete a toxic fluid from the huge parotoid glands behind their eyes, and they are very difficult to kill. However, in Costa Rica they are native and they help to control the populations of insects and other vermin. Nevertheless, they are still a common, weedy, species that I imagine can be a bit of a pest sometimes. I ran into many cane toads; the first and largest was wedged in a crack at the base of a tree trunk. I handled the beast with my hat, to avoid contacting any oozing venom, and I made everyone stand clear, since these toads can actually squirt their toxin a short distance. These amphibians are everywhere… some members of our group stayed in a house through which a toad hops every evening on its nightly rounds.

Hoffman’s two-toed sloth (Choloepus hoffmanni). I have loved sloths since I was a child, as evidenced by my sloth-themed sixth birthday party. Despite extensive travels in Latin America, though, I had never seen one in the wild before. We observed several on this trip, including one happily munching a vine while hanging on a barbed-wire fence next to the road. The best show was a pair of two-toed sloths hanging at eye-level on a fence one night at our hotel. We could have reached out and touched them, but nobody wanted to disturb them and risk getting scratched by their enormous claws or contracting any diseases they might carry. The sloths didn’t seem to mind at all that some humans were staring at them and shining lights on them. Slowly, gracefully, they manipulated their shaggy bodies around and through the fence, orienting their limbs in all of the many positions of edentate yoga, sampling the vegetation in an apparent state of pure inner peace. Their hair ran from belly to back, the natural direction for these usually upside-down beings. I don’t think either one even realized that there was another sloth on the fence until they had both moved about a foot apart from each other, because they reacted to the encounter with a start of surprise. They pointed their snouts quite close to each other and opened and closed their mouths a few times, possibly smelling or threatening each other. After deciding that they posed no danger to each other, they resumed their solitary feeding.

Green sea turtle (Chelonia mydas). Tortugeuro National Park on the Caribbean coast was founded to protect the nesting grounds of the green sea turtle. They take turtle conservation very seriously there. You can’t just walk down the beach at night when the turtles are laying their eggs. Instead, you have to have a guide. Certified turtle watchers patrol the beach, and when a female comes ashore, they let her dig a hole and start laying her eggs in peace. Only when the first eggs have fallen do they radio the guides, who bring in the curious tourists. No flashlights, cameras, or cell phones are allowed, and tourists must walk in pairs and speak in hushed voices. The only light comes from a small flashlight covered in red paper, to minimize disturbance to the busy mother. We saw three turtles: one laying her eggs, one burying her eggs with sand, and one returning to the ocean. Sea turtles are truly massive animals, and it’s humbling to watch one deliberately engaged in this essential act of reproduction. The eggs are the size and color of extra-large gobstoppers, at least under the meager red light. A substantial pile of eggs eventually fills the hole, and if the mother is lucky, one of them might survive to return to the nesting grounds.

Greetings from the Department of Microbiology and Immunology, Vanderbilt University, Nashville, Tennessee, where I’m ensconced in the lab of Dr. Louise Rollins-Smith. After years of studying genes encoding antimicrobial peptides, as of a week ago I still had yet to handle an actual antimicrobial peptide, so I am here learning how to work with them. Today I learned how to extract peptides from frogs. You give the frog a shot of norepinephrine, a stressor hormone that induces the frog to release the contents of its skin glands. You place the frog in a beaker of buffer for about fifteen minutes, and the frog secretes its antimicrobial peptides into the buffer. You add some acid to denature any enzymes that might break down the peptides, and you’re good to go. Other researchers use electroshock methods to induce peptide secretion, but that sounds painful. Alternatively, if you know the sequence in advance, small peptides can be synthesized artificially.

I’m also learning how to assay the antimicrobial activities of a peptide. You add known concentrations of sterile peptide to known concentrations of bacterial or fungal cells (for fungi, you can actually count the cells under a microscope to calculate how many you have). You incubate them for a day or a week, depending on the microbe being tested. At the end, you assess microbial growth by how cloudy the solution is, since cells will block the light (using a spectrophotometer, of course, not just your naked eyes). Keeping everything sterile takes some effort (working under a hood whenever solutions are exposed to the air, passing solutions through filters, using lots of sealed and disposal tubes and tips, etc.). I’m accustomed to keeping an area free of PCR product, but keeping an area free of microorganisms is slightly different. It also turns out that antimicrobial peptides don’t always want to go into solution and stay there, which in practice can be a bigger issue than I ever would have imagined.

In general, there is still a sizeable gap between evolutionary geneticists and protein biochemists. The former group is good at identifying nucleotide substitutions that have been favored by natural selection, and the latter group is good at assessing the functional differences among protein isoforms, but only recently have the two fields started to merge. We still have a lot to learn about how non-neutral genetic differences identified by statistical tests of DNA sequence data translate into differences in protein function.

My pursuit of frog toes, originating in Illinois, has now continued across several Midwestern states. A tip from the Wisconsin DNR sent me to a muddy farmer’s field near a spring, where I easily captured two dozen pickerel frogs in broad daylight while curious cows looked over my shoulder. When collecting on private land I always feel the need to work as fast as possible, both to impress the landowners with my herpetological prowess and to promptly give them back their privacy. Luckily, these cheese-head frogs complied. In contrast, I only found a handful of plains leopard frogs in central Iowa, not enough to justify taking their toes, but I was on state land in the middle of nowhere and there was no one I needed to impress. In Michigan my field site was a military base. I might have been denied entry at the security gate but for the fact that I was accompanied by the president of the Michigan Society of Herpetologists, who had been there before and could convince the top brass to let me in. If I had accidentally wandered into the wrong section of the base, I could have been shot by practicing soldiers, so I made sure to read the map extra carefully. It was all worth it, as a riot of the world’s best-protected pickerel frogs were waiting in a seepage area to donate their toes to science.

All of these places were full of wildlife other than the frogs I was chasing, of course. Gray tree frogs and spring peepers called at night. These hylid frogs are much louder than the ranid frogs I sought, and it was often a challenge to listen for the call of leopard frogs over the deafening din of their smaller cousins. Waterfowl were everywhere; I even stumbled upon a Canada goose nest where three eggs were hatching, and I managed to observe the shells slowly crack and peep without being attacked by the irate parents. I won’t really miss the wood ticks, which I inadvertently collected even more prolifically than I did frogs.

The dried toes are now safely preserved in plastic tubes inside boxes, awaiting DNA extraction. Who knows what lessons might be gleaned from there genes? The remarkable thing is, I feel like I’ve learned so much already just by collecting them.

I went to Hawaii a few weeks ago, for a good friend’s wedding (seems I only travel for weddings these days). I have been to Hawaii several times and I must say I love the place. I probably wouldn’t want to live there for very long because of the lack of seasons and because the sheer isolation and limited land area of the archipelago would probably drive me nuts. But it’s a lovely place to visit, no doubt.

Hawaii is superficially very beautiful, but with my biology goggles on I can’t help but see it for what it is: an environmental disaster. Specifically, Hawaii is a sad example of how human-mediated invasions of alien species can radically change natural ecosystems. Insane numbers of introduced organisms have been ferried over to Hawaii since the first Polynesians pushed their canoes ashore. These new species can outcompete and consume natives, introduce new diseases, and destroy habitat. Now the rate at which new species are arriving on these once isolated islands is millions of times higher than it was before humans were in the mix. We have introduced great numbers of weeds and other plants, invertebrates, fish, amphibians, reptiles, birds, and mammals. Hawaii’s native bird species have been decimated by disease and introduced predators; half of all the plant species now on Hawaii are non-native. Boo!

I was on Maui during my recent visit. I saw some exotic-looking birds that most tourists probably assume are Hawaiian endemics. Nope. I’ll bet that just about every bird I saw was an introduced species. And who knows how much of the lush plant life I saw while hiking in Iao Valley (see photo above) was composed of weeds and such from all corners of the world? I couldn’t even get excited when I found a cane toad hopping in the grass of a beach side resort one night– Hawaii has no native amphibians or reptiles.

Depressing…

I have just spent the past week collecting leopard frog toes in western Illinois, from which I plan to extract DNA for genetic analysis. I survived lightening storms, mosquitoes, snapping turtles, snakes, coyotes, encounters with local law enforcement, and the peculiarities of rural culture hundreds of miles from the part of the state that elected Barack Obama. Armed with a dip net, a headlamp, a pair of scissors, and a bottle of Everclear (to sterilize the scissors, not to consume), I stalked ponds and flooded roadside ditches at night looking and listening for specimens. Although toe-clipping is unpleasant, it is the least-invasive way to reliably get large quantities of DNA in the field, while simultaneously marking frogs so you know if you happen to catch a repeat victim (not possible with other methods like buccal swabbing). The locals were generally indifferent to my presence, since both fishing and bullfrog gigging are common regional activities, and I just looked like a normal guy with a net. When they found out what I was really up to, they were amazed that I would think to travel all the way to they neck of the woods for research, and they helped me herp and gave me beer.

My first site was in Jackson County, Illinois, on the fertile Mississippi River floodplain. I was seeking plains leopard frogs, Rana blairi, and southern leopard frogs, R. sphenocephala. These closely related species can be distinguished by their spot pattern, the lay of their dorsolateral skin folds, and their call. R. sphenocephala has a rapid call which sounds frustratingly like a taunting laugh while they’re evading capture; R. blairi produces a slower, softer cluck. This muddy countryside on the cultural and biogeographic border between the Midwest and the South was an ideal place to look for a wetland supporting both species. I found a few individuals of both in a roadside ditch one evening, and I decided to try to collect full population samples there (to do population genetics, you need populations… usually at least 20 specimens). Unfortunately, there weren’t a lot of frogs in that ditch, and after three nights I had only collected a handful of each species. I did encounter many other neat amphibians, including bullfrogs, cricket frogs, toads, and a lesser siren (a foot-long eel-like aquatic salamander with no back legs, apparently named after the mythical seductive women of the sea by the same guys who thought that manatees look like mermaids). Each night I hunted until the wee hours of the morning, when I would return, exhausted and blairi-eyed, to my campsite. Thus, I am extremely fortunate that a fellow herp enthusiast happened to see me on the side of the road. He directed me to some ponds less than a mile away, where veritable plagues of both species were calling. In two more nights, I had easily collected more than I needed.

Next, I traveled north to Pike County, Illinois, looking for pickerel frogs (Rana palustris… actually another member of the leopard frog posse). R. palustris is a very attractive frog, with paired, square dorsal spots and bright yellow underparts. It often takes shelter in caves, so I searched along a stream near a cave, where other herpetologists have had great success finding this species. Almost all the frogs were located in a very specific section of the stream, suggesting that there could be a frog-sized entrance to the cave there that they are using. Also, in addition to the standard cricket frogs, bullfrogs, and toads at the site, I found several long-tailed salamanders.

To assess geographic variation in these species, I’m going to collect samples in other Midwestern states during the next few weeks. Updates to follow…

On March 19th, I drove up to Portland, Oregon to attend the spring national steering committee meeting for Partners in Amphibian and Reptiles Conservation (PARC) . Here is how PARC is described on their website:

Partners in Amphibian and Reptile Conservation (PARC) is an inclusive partnership dedicated to the conservation of the herpetofauna–reptiles and amphibians–and their habitats. Our membership comes from all walks of life and includes individuals from state and federal agencies, conservation organizations, museums, pet trade industry, nature centers, zoos, energy industry, universities, herpetological organizations, research laboratories, forest industries, and environmental consultants. The diversity of our membership makes PARC the most comprehensive conservation effort ever undertaken for amphibians and reptiles.
Reptiles (alligators, crocodiles, lizards, turtles, the tuatara, and snakes) and amphibians (frogs, toads, salamanders, and caecilians) have suffered from a broad range of human activities, due in part to the perception that these animals are either dangerous or of little environmental or economic value. We know now that they are important parts of our natural and cultural heritage.

I have recently joined PARC, but am not a member of the committee or anything. I attended the meeting not because I would have anything to say about how to “steer” the organization, but because I want to get involved in the conservation of herps. I wanted to see what PARC is all about. I have felt deeply connected to amphibians and reptiles for as long as I can remember. My graduate research has been on the population genetics of frogs and I hope that it will someday benefit these animals. To date, however, I have not done any real on-the-ground conservation work. Being involved with PARC is a step in the right direction.

One of the really cool things PARC does is produce regional Habitat Management Guidelines for amphibians and reptiles. The Northwestern division of PARC is still working on the Guidelines for this region, which are scheduled to hit the press in November of this year.

My friend Sam took his four-year-old daughter, Audrey, on a hike in the Columbia Gorge last week. They found a little Cascade torrent salamander (Rhyacotriton cascadae) tucked in the moss and ferns beside the trail. Audrey held the salamander and was enthralled. She talked all the way home about how they needed to find more salamanders. Sam says she is still talking about it. Little kids like Audrey, and everyone else for that matter, should always have the opportunity to go out into wild places and have happy experiences with creepy crawly herps and bugs, fuzzy-twitchy mammals, vociferous birds, and all the multifarious denizens of the Outside.

Though I feel that all forms of life have intrinsic worth and deserve to be conserved (except, that is, for some a-hole humans), I have chosen to champion the reptiles and amphibians. Now I just need to actually get out and DO something!

I’m planning to collect toe clips from frogs in the Midwest this spring, including from the plains leopard frog, Rana blairi. I’ve been doing preliminary work with two dried up specimens of R. blairi that were shipped to our lab years ago by a commercial frog supplier. I used these specimens to optimize my PCR conditions and conduct some basic genetic analyses, but I need more samples to assess genetic variation within this species. In addition to my planned field season, I have been contacting museums and other herpetologists for previously collected specimens, and I was excited to receive the first of those not long ago.

As I began to study these new specimens, I soon realized that they were genetically quite distinct from the two dried up frogs in our lab. This prompted me to scrutinize our two lab samples a little more closely, and I discovered that they are, in fact, not R. blairi. They appear to be southern leopard frogs, R. sphenocephala, or possibly some sort of weird hybrids. Remember, these frogs were raised by a commercial supplier who keeps several species of frogs, and it appears that these two frogs were incorrectly identified as pure R. blairi. Of course, I can’t rule out that somehow they got mislabeled after they arrived in our lab.

Many biologists depend on specimens collected and identified by someone else, and this involves a great deal of trust. You have to believe that the data someone gives you are valid, or you can’t use them. Too much trust can lead to problems, though, as I just learned the hard way. Whenever possible, scientists should independently verify that their samples are what they think they are.

Fortunately, I shouldn’t have to change my field season itinerary too much. It looks like R. blairi will still be a good species to target for my study, even though everything I thought I knew about R. blairi genes is wrong. But I need to hurry up and study the putatively real R. blairi samples some more before I make my final field work plans.

If it’s still March 20 by the time you read this, happy World Frog Day from us at SC!