Sir David Attenborough takes us on a journey through the weird and wonderful world of frogs, shedding new light on these charismatic, colorful and frequently bizarre little animals through first-hand stories, the latest science, and cutting-edge technology. Frogs from around the world are used to demonstrate the wide variety of frog anatomy, appearance and behavior. Their amazing adaptations and survival techniques have made them the most successful of all amphibians.
Just a heads up for my fellow frog fans. Nature is airing a documentary on frogs on June 25th. YAY! Here is a description from the website.
Don't miss it!
DYT Blogger: So, Mr. Phrogg--
PPP: Oh, please, call me Phineas.
DYT Blogger: As you wish. Phineas, what is it like to share the big screen with stars like, George Cluney and Sandra Bullock?
PPP: Well, I have to say, that they are consummate professionals. It was a real honor. Both of them were so very easy to work with. They're like Michael Jordans of the film world. Not only are they fantastic, but they make everyone around them better too. I wish them the best of luck in their respective careers, and you can bet that they're on my short-list should an appropriate role be available for them in one of my future projects.
DYT Blogger: That's very gracious of you, Mr. Phro--er, I mean Phineas. Did it bother you at all that they seemed to get more screen-time than you?
PPP: Oh, not at all. I feel like they were a great lead-in to my scene, which was, of course, the climax.
DYT Blogger: ...and a captivating climax it was, I'll say.
PPP: Thank you.
DYT Blogger: Although, it did seem a rather small role for an artist of your stature...
PPP: There are no small roles, only small minds, sir.
DYT Blogger: Righto! So why, exactly, weren't you featured earlier in the film?
PPP: Simple: Logistics.
DYT Blogger: What do you mean?
PPP: They simply couldn't find a space suit of suitable proportions to fit me--although your point is well-taken--next time I think I'll instruct my agent to negotiate for a custom-made space suit.
DYT Blogger: Perhaps for a sequel?
PPP: If there is a sequel. My time is valuable, and--how shall I express it--my dance card is filling up. Perhaps though i might be able to squeeze in another cameo.
DYT Blogger: So tell me, or, let's say, tell the world, who have been some of your inspirations and mentors helping you to launch your illustrious career? Kermit the frog, perhaps?
PPP: Ahem, you're walking on thin ice there.
DYT Blogger: Thin ice?
PPP: That's a bit offensive, if you don't mind.
DYT Blogger: Oh, so sorry Mr. Phrogg, no offense intended.
PPP: Well, I'll just chalk it up to your ignorance. let me just say this, Kermit is, to frogs, what blackface is to African Americans--not funny. In fact, an insulting caricature.
DYT Blogger: Oh, I apologize again.
PPP: ...and let me add, that like most of Hollywood, I'm quite tolerant of, how shall I say this, "unusual" relationships. But I can't wrap myself around Kermit's obsession with--I can hardly say it--a pig. That "Miss Piggy" is not only not a frog, she isn't even an amphibian. Beastly! (PPP was breathless at this point.) Sorry. I need a moment to recover from the thought.
DYT Blogger: Perhaps we should change the subject.
PPP: Yes, let's do so. Let's get back to the original subject: Me, that is.
DYT Blogger: Perhaps you could share who some of your inspirations are?
PPP: Well, this is exactly about me, but I'll roll with it. Not exactly a model, but someone I admire is Peter Dinklage.
DYT Blogger: The dwarf actor in "Game of Thrones?"
PPP: Yes. Now there's and actor who goes against the grain. Before Peter it seemed that most dwarfs were portrayed as ridiculous. Remember "Snow White and the Seven Dwarfs?" Similar to him I seek to make the world treat both frogs and toads with the distinction and seriousness that is long overdue.
DYT Blogger: Of course.
PPP: Inexcusable stereotyping. But Dinklage broke that stereotype. On "Game of Thrones" he's clever, conniving, with extraordinary diplomatic intellectual guile, and quite the ladies man too.
DYT Blogger: That he is.
PPP: Of course he's not nearly as fecund as even the average frog, he is, after-all, a mammal. But anyway, I'm trying to separate from ridiculous frog-stereotyping in the same way. What Sidney Poitier is to racist black-face, Dinklage is to anti-dwafism, and I intend to be against anti-frogism. This, I hope, will be my cultural legacy. Now, I'm very sorry, but I have to wrap this up. My agent has arranged a meeting with Stephen Spielberg and I'm already ten minutes late.
DYT Blogger: Thank you sir.
PPP: My pleasure.
That, DYT Blog readers, is the transcript of the interview with Phineas P. Phrogg, who I am sure will be showing us great things, no matter what pond he winds up in.
I love frogs. Okay, I've said it. Everyone should love frogs. Okay, you're thinking, he's crazy. Yep, crazy 'bout frogs.
When I was in college, I was employed in a work-study job as frog-feeder. Actually, I started as a salamander-feeder, but when the funding ran out I switched. Talk about transferable skills! Anyhow, in both jobs I had the highly-intellectual task of wiggling small slices of liver in front of amphibian mouths. The frogs were actually oriental fire belly toads (Bombina orientalis). Note: There really is no taxonomic distinction between toads and frogs; they're all anurans. If you want to compare the two, here and here are a couple links to get you started. The toad colony was the project of Mark Ellinger, the Southern Illinois University Zoology Department Embryology Professor. I loved frogs and toads long before I went to college, but my experience there enhanced my love of all things anuran. I really don't remember why Dr. Ellinger kept fire bellies rather than the much more common frog studied in developmental biology, the african clawed frog (Xenopus), but I'm glad he did, fire-bellies are a whole lot prettier.
Okay, here's a story for you. One of the fun things about fire belly toads is that you can induce them to breed by injecting a small amount of human chorionic gonadotropin (HCG) into the dorsal lymph sac. Biosupply companies, I was told, acquire HCG extracted from the urine of pregnant women. I guess there is enough similarity between human HCG and some frog molecular equivalent to allow a cross-species effect. By morning, after injecting both the male and female, they were mounting and laying eggs. Kewl. Then we could watch the embryonic development on a dissecting microscope. It was fascinating to watch the fissures form in the dividing embryo, the invagination of the cells, and the eventual development of the tadpole. I recall explaining this process to a couple of friends of mine. They seemed surprisingly interested in the HCG. "You can get this stuff?" one asked. "Well, yeah, we stock it in the lab," I responded. Then it struck me what he was getting at, "NO! You can't have any! And it wouldn't work on humans anyhow!" Sheesh. Some people. (Actually, HCG is used clinically as an ovulation inducer, but that's a far cry from expecting "results" from slipping it into someone's drink.)
By the by, let me digress here with a rant about the HCG diet program that some nefarious medicos are still using to swindle people out of their cash. The HCG diet was championed by Albert T. W. Simeons who published a book in 1954 entitled "Pounds and Inches." The rationale behind HCG and weight loss is that HCG signals the hypothalamus to move nutrition to the developing embryo. Thus, when it is injected, or sometimes administered orally, in conjunction with a 500 calorie a day diet, the recipient loses weight. Five humdred calories a day! Who wouldn't lose weight! There are even homeopathic concoctions of HCG. Which means that they take something that doesn't work--and dilute it until it isn't even there. Quack! Quack! Quack! ('scuse me, I would say I have a frog in my throat, but that would be an insult to frogs.) The FDA is onto these scammers. If you want more info, check here.
Okay, enough about that, back to frogs. It really is much more impressive in person, but I found a couple of time-lapse vids of frog development and one very amusing one about some "true facts." Enjoy.
Fire Belly Frogs. Awesomely beautiful (And they know it.)
This croc better be careful. He's about to have his lower jaw ripped off by this frog! From National Geographic.
The hula frog was, as in the Monty Python dead parrot sketch, NOT dead. He was, apparently...only sleeping. No doubt about the fact that frogs are a highly endangered group, with about a third of them in trouble. So, it is good news that one species, the Hula Painted Frog, has been found alive. This gives new hope to the possibility that other extremely-hard-to-find frogs, are just that: hard to find and not gone. More info at this very-informative National Geographic article.
Gastric brood frogs stand out for their peculiar reproduction habits. After the usual external fertilization process, most frogs abandon their progeny. But, in a fascinating departure from the norm, the female gastric brood frog ingests about forty fertilized eggs and the young tadpoles hatch and develop in the mother's stomach. During the incubation, the mother doesn't eat, although apparently she does digest some of the embryos. When the incubation is sufficiently advanced, her lungs collapse and the mother and relies on gas exchange through the skin. After about six weeks there is a "re-birth," well, regurgitation really, of about 20 to 25 fully-developed froglets. This behavior reminds me a little bit of Darwin's frog, in which the young incubate in the vocal sacs of the male, or Egyptian mouthbreeders, in which the eggs and young are protected and reared in the mouth of the mother.
Sadly, both species of gastric brooding frogs, which resided in Eastern Australia, became extinct in the mid-1980s. What a shame. A loss of an interesting critter.
But is there hope for the species yet? Recently, a research group led by Mike Archer of the University of New South Wales in Sydney in Australia has reported the transfer of frozen gastric brooding frog DNA genomes into donor eggs derived from the Great Barred Frog in which the donor DNA had been inactivated. The result of the so-called "Lazarus Project," was the creation of a small mass of embryonic cells containing gastric brooding frog DNA. None of the embryos survived beyond a few divisions.
One matter of clarification, even if the embryos had developed into adults, it would be a bit of a stretch to call this even an abortive "rescue" of the species. There are profound epigenetic events that are mediated by the maternal RNA, i.e. the RNA in the donor oocyte, which have been documented in several organisms, including frogs. It would be more accurate to say that experiment resulted in a "rescue" or resuscitation of the nuclear genome of the gastric brooding frog. Nevertheless, the research team is optimistic that using refinements of the technology they will soon be available to clone and raise adult frogs. Similar experiments were performed in the creation of Dolly, the sheep, the first vertebrate cloned from an adult cell, although the donor oocytes were derived from the same species.
This is of broad academic interest, since there are similar experiments underway or contemplated to clone a number of extinct species, such as the passenger pigeon, the great auk, and even wooly mammoths (using modern elephants as egg donors).
What does this all mean? Recently, a TED-X conference sponsored by National Geographic, was convened to discuss the ethical and practical issues related to "De-Extinction." Although, videos of the conference have yet to be released, it will be interesting viewing.
Where do I come down on this issue? I really don't know, but I offer the following: 1)I don't believe that any of these creatures should be released into the wild. Repopulating North America with semi-pseudo wooly mammoths or frankenfrogs? Bad idea. 2)I really wonder what conclusions can be drawn from the possible results of these experiments? Can we ever draw definitive conclusions about the behavior and biology of these "resurrected genomes?" Even the Dolly experiments, using donor eggs from the same species, resulted in adult animals with serious health problems and I expect that using donor eggs from differing species will result in even greater deviations from normal adults.
Although the expansion of humanity has had cataclysmic consequences on both the ecology of the planet and the destruction of species diversity, it is believed that 99% of the known organisms that ever lived have become extinct. Most of these extinctions preceded human beings. Extinction is not exceptional; it is the norm in planetary history.
Personally, I wonder if we would be better served by rescuing charismatic animals (like tigers and blue whales), and studying ways to try and prevent the extinction of surviving species, primarily by protecting and preserving habitats and ecosystems, rather than trying to resurrect lost organisms. This would seem to me to be a more efficient and valuable use of scarce scientific resources. Agree or disagree, that's my take. Rebuttal is always welcome.
Scot Bastian Ph.D. is a scientist and artist who lives in Seattle WA.