Animal of the Week February 12, 2007 -- Funny little frog in your throat

Happy Chinese New Year! I have already done pigs, look http://animal-of-the-week.blogspot.com/2005_03_01_archive.html, there they are.

So this week's animal of the week is not inspired by the Chinese zodiac. Rather, it is Rheobatrachus silus (platypus frog, southern gastric brooding frog). This tiny Australian frog sadly is no longer with us, but until the early 1980s the Blackall and Conondale Ranges in Southeastern Queensland, Australia, rang with the chirruping of thousands froggies going a courting. Small, green, and quite froglike, they would be unremarkable but for their novel approach to reproduction.

Once her clutch of eggs was fertilised, the female would proceed to eat them. But rather than being dissolved by stomach acids, a compound secreted by the eggs switched off the female's normal digestive function and there the eggs developed. Tadpoles then hatched from the eggs and developed into little froglets. The female could not eat while brooding her offspring and her stomach would swell to fill nearly the entire body cavity, to accomodate the froglets. When the young had developed into fully formed little frogs, the female then would vomit up her children ("midwife, can I have a glass of water, I have a froglet in my throat")!

If surprised or threatened, the gravid female could vomit up her young at any time, and the young could mature successfully outside of the body. Although they laid about 40 eggs, only 20 or so young would ever hatch, perhaps the earlier eggs were digested and were sacrificed in order to switch off the usual gastric machinations, or perhaps the tadpoles and froglets used them as a source of food whil confined to the maternal belly.

I am not the only person captivated by these bizarre things, I found this on a site dedicated to refuting evolutionary science with the argument of irreducible complexity. Although it is an old piece, there argument is slightly undermined by the last sentence of the first para, the frogs have not been seen since 1981 and are listed as extinct by the IUCN.

http://www.darwinismrefuted.com/irreducible_complexity_09.html

"The miraculous reproduction system of Rheobatrachus silus explicitly invalidates the theory of evolution, since the whole system is irreducibly complex. Every step has to take place fully in order for the frogs to survive. The mother has to swallow the eggs, and has to stop feeding completely for six weeks. The eggs have to release a hormonelike substance to neutralize stomach acids. The addition of the extra protein-rich yolk to the egg is another necessity. The widening of the female's oesophagus cannot be coincidental. If all these things failed to happen in the requisite sequence, the froglets would not survive, and the species would face extinction [PH: face it, they're looking at it's rear view].

Therefore, this system cannot have developed step-by-step, as asserted by the theory of evolution. The species has existed with this entire system intact since its first member came into existence. Another way of putting it is, they were created."

Not really a believer in that view myself, but I'll leave y'all to make up your own minds.

Ciao!

Peter Hayward
Head Keeper
Animal of the Week