Song of the Katydids

With respect to completing the Grid for September, I was full of valiant intention, prepared to squeeze hikes in at odd hours, take the month’s last week off entirely, whatever it would take — but there was still the sore ankle to contend with.  So I settled for a 6.6-mile round-trip to Panther Mountain, at night since that was the available window, and instead of covering a lot of ground, I’d look and listen and ponder.

Odie and I showed up at the Giant Ledge parking area around 7:30 PM on a warm fall evening and began hiking up the trail.  On a previous occasion, the initial climb had seemed like a tumble of rocks, but this time I noticed a number of stone steps built into the slope.  Maybe that’s the difference between going fast and slow.

The grade moderates after the initial climb, and then the path hops across flat stones placed to keep feet out of mud, but conditions tonight were dry, and for the barefoot hiker both damp dirt and smooth stone are pleasing surfaces, and so I strolled along cheerfully while Odie ranged ahead.  A katydid was calling from somewhere in the darkened forest to the left of the path, a raspy klack-klack-klack like someone clipping away with a pair of rusty scissors, and a little while later there was one on the right.  These insects are often described as singing in “choruses”:  I’ve read that the males synchronize their singing within groups and that the groups answer back and forth, although for all the times I’ve listened, I’ve never discerned any clear pattern.  I’ve often wondered did “synchrony” mean that two insects in the same tree would sing in concert, or would katydids coordinate across an entire forest?  In the back of my mind was the question as to what exactly does “order” mean, because a pattern of sounds that might be full of meaning to a katydid might be nothing but noise to those ignorant of their language, like me.  In any case, these two individuals were too far apart to coordinate their songs, so the point was moot.

The trail was dotted with fallen leaves, including red maple, although the leaves were more frequently dark purple than flashy crimson.  Last fall I’d written extensively about red maples, and perhaps I’d exhausted the topic, because now they passed by underfoot without stirring any reaction in me.

As we neared the climb to Giant’s Ledge, the smell of campfire smoke drifted through the forest.  There were sounds of music and people talking; we crept by.  A small snake slithered out of our way, and I cautioned Odie to leave it alone.  A toad hopped to the side, and coal skinks slinked among the rocks.

We paused for a moment at one of the vantage points along Giant’s Ledge.  Woodland Valley lay below us, completely dark but for a handful of lights in the center, but it might as well have been a mile-wide orchestra hall with us sitting in a high balcony, for now the sounds of an insect symphony rose up from the depths, and against a background hum of crickets the katydids were clacking away with great spirit.  To the north one particularly loud katydid (or perhaps it was a group singing together in perfect unison) initiated a raspy call (they make this noise by rubbing their forelegs together or “stridulating”) and then a group in the middle jumped in, and then the signal was taken up by a third group to the south, the theme swirling around like a motif played first by the strings and then by the brass, until the rhythm seemed to be circling around the valley like a horse on a track.

We stepped down into the saddle before Panther Mountain, finding the trail littered with small black berries.  I took a tiny tentative bite, and it seemed to be black cherry (Prunus serotina), reminiscent of conventional cherries you’d find in a grocery store but not nearly so plump or sweet.

We scrambled up the final climb to Panther’s summit (at a couple of points Odie accepting a boost) and the wind began to stir.  And at the summit it was blowing steadily.  I yanked shirt and sweater out of my pack, then sat down to look and listen for a little while.  The stars shone above, but the eastern sky was obscured, and the horizon was streaked with faint bands of light, which might have been the reflection of Kingston’s city lights on the underside of clouds, but it was hard to be sure.

The wind blew constantly up here, sometimes speeding up, sometimes slowing down, but never pausing, and it made a rushing or tearing sound as it sliced through the needles of the fir trees that surrounded the summit ledge.

I thought of what Thoreau had written in Walden, of how he was anxious “to stand on the meeting of two eternities, the past and future, which is precisely the present moment; to toe that line.”  I didn’t look at my watch, because what the clock said wouldn’t matter up here, the time was just “now,” and while the distances reached out in all directions, the summit was just “here.”  Odie and I hung out at our “here-now,” as if we were in a tiny boat bobbing along in the great ocean of space-time, and nothing much happened except a star turned out to be an airplane and it banked and flew off to the south.

After a little while we got up and headed back, at one point passing a solitary cricket resting on a rock.  We paused once again at Giant’s Ledge and looked out over Woodland Valley.  Now the wind blew at intervals, a wave rolling in, the birch and maple leaves fluttering against each other, and then the air becoming still.  The songs of the katydids reached us intermittently between the waves of wind, and the voices of those soloists we’d heard in the north and east rose above the accompaniment, but whether they were synchronized or singing back and forth was impossible to tell, but I did notice that sometimes they klacked in threes, sometimes fours, and sometimes twos, but this didn’t help me understand their purpose.

On the descent from Giant’s Ledge, the maple leaves lining the path began to draw my attention:  dark purple still predominated, but mixed in with brown and yellow, and then I started to notice flashes of crimson, and when I focused on them, the colors became startlingly bright, or the leaves were splotched with green in curious intricate patterns.

We were once again crossing that flats, stepping from stone to stone or sometimes in cool damp dirt, and here were those same two katydids, the one on the right and the one on the left, but I found this time there was a point in between where both were audible, and they were indeed answering back and forth — at least it seemed so at first, but after a little bit their calls converged, and then separated again.  Like watching an ambulance with two lights flashing at different rates.

It was past midnight, and the drive back home was tiring (at one point I swerved to avoid a possum walking in the middle of the road).  Back at home, a katydid was singing from the tree outside our house, but instead of the characteristic three klacks (which are supposed to sound like its name katy-did) or four klacks (katy-didn’t), or a mix, every measure in this song was two klacks, and the song stayed this way for a long time, although the interval between klacks was not constant.  At least it stayed this way as long as a tired mind would listen.

I sat in my sunny doorway from sunrise till noon, rapt in a revery, amidst the pines and hickories and sumachs, in undisturbed solitude and stillness, while the birds sing around or flitted noiseless through the house, until by the sun falling in at my west window, or the noise of some traveller’s wagon on the distant highway, I was reminded of the lapse of time.

— Henry David Thoreau, Walden


Postscript:  Scientists theorize that instead of coordinating songs with peers, male katydids are constantly trying to jump in first, as the earliest call seems to attract the females.  Modulations in rhythm and number of klacks are an attempt to disrupt other males’ songs.  It’s a game of constant one-upsmanship, and what some people perceive as synchronization is in a sense accidental.

In many animals that use rhythmic acoustic or bioluminescent sexual communication, neighbouring males precisely synchronize their signals. This event has previously been interpreted as a development whereby cooperative individuals benefit from maintenance of species-specific signalling rates, minimization of predation risks, or maximization of peak signal amplitude of a local population. Our recent findings on chorusing in the neotropical katydid Neoconocephalus spiza (Orthoptera: Tettigoniidae), however, refute for this species all three hypotheses that claim that synchrony is adaptive. Instead, we demonstrate that synchrony can be an epiphenomenon created by competitive interactions between males jamming each other’s signals. The mechanism generating this interference is shown to be an evolutionarily stable strategy (ESS) maintained under sexual selection for exploiting a critical psychoacoustic feature: females orienting toward signalling males choose the leading call in a closely synchronized sequence.
Katydid synchronous chorusing is an evolutionarily stable outcome of female choice. https://www.researchgate.net/publication/232710356_Katydid_synchronous_chorusing_is_an_evolutionarily_stable_outcome_of_female_choice [accessed Sep 22, 2017].

Running the Long Path is available on Amazon

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Song of the Katydids

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