The Xena Paradox

Inspired to learn that paper wasp faces are as different as snowflakes  (Sheehan & Tibbets, 2008), Nancy set out to identify the frogs who frequent our pond. The first to be studied, and named, was Xena, who has a distinct little swish on her left upper lip. We first introduced Xena as the bold frog, who allowed close encounters rather than diving for the bottom at the slightest approach. Nancy deemed it a female, based on physical characteristics (the size of the tympanum relative to the size of the eye, and its placement along the dorsal lateral ridge). Bold female, warrior princess, Xena. Nancy observed Xena for months. Quiet. No frog calls.

Then we scrutinized the frog fight. “Xena” and a smaller male. “Xena” definitely in command. Woman on top? Warrior princess? Most unladylike behavior for a frog. Typical frog fights are between males.

Calmly This Time

Next day, Xena was submissively sitting underneath the loser of yesterday’s battle. Ladylike again.

For a month now, “Xena” has been emitting male mating calls. There are two calls. The first is very elaborate while the second call is more typical.

Gender Examples
Left to Right: Male, female, Xena.

Male or female? Someone suggested that frogs occasionally change gender. My limited reading does confirm that at least one species has been observed to undergo spontaneous sex change. But I find no reference to that behavior in green frogs. There is evidence that female green frogs emit mating calls, but quietly. Not like this! But there was that long, complicated call. Hmmm.

Do we have two look-alike frogs, one male, one female? If there are two, then both have that bold, I’m-not-afraid-of-you, characteristic. Why do we never see both at the same time?

Can you figure out which frog is Zeno (aka Hercules)?

Nancy has been reviewing her photos and has tentatively concluded that there are two frogs. The identifying mark she has been going on is slightly different  between Xena and what’s-his-name. So we need to name the male. Zeno, of paradox fame, comes to mind. (Okay, technically, we are not dealing with paradox here, just mystery. Grant us just a little bit of artistic license.) Or should we forego alliteration and go with Xena’s partner, Hercules?



Add One Snake

“There is a snake in the pond,” Nancy informs me.

DSC03559I watched for a while before noticing a different kind of stirring of the water. Then, the head appeared. Alert. Curious. Tongue seeking clues on the wind.DSC03573

DSC03630It’s a garter snake. We watched it slide out of the water, more than two linear feet of it before the tail finally emerged. It hid under a nearby fern, then later was back in the pond.

We have noticed no frog-sized lumps in its sleek length, so speculate that it  feeds on eggs and small larvae as it hoovers along the edges of the pond, in and out of the gaps between stones.