Naturespeak A naturalist's view of the world

November 7, 2007

Natural Curiosities

Filed under: Uncategorized — wykes @ 9:51 pm

  Curiosities in nature can come in many forms.  Some are just plain freakish and others are just everyday wonderful.  In reviewing some information about Victorian taxidermy (don’t ask me why I was looking into such an obscure subject) I was faced with an image of an eight legged, three tailed stuffed kitten. The odd little thing was mounted nearly 150 years ago with seven full legs in standing position and at least two of the tails and the eighth leg sticking out of the back. I’m sure the original mount has long since crumbled into dust, but the ancient photo of it gives it an even “curiouser” appearance.  On the other hand, normal live kittens (and this coming from a dog person) are disgustingly adorable and fall into the category of an “everyday wonderful” type curiosity.

  When compared to the Octokitty, the freakish curiosity I offer as a fresh example is pretty tame – how about a two headed maple leaf.  I’m talking not one, but two! Yes, as shocking as it sounds, there is a red maple tree out there that is shedding leaves consisting of two leaf blades joined by a common stem (take a look here at this shocking revelation).  You can supply the Psycho music when this image pops up on your screen.  I’ve nothing to say about these things except to acknowledge that trees are frequently subject to random mutations.  These changes can be induced naturally by the sun’s radiation and don’t necessarily mean a pollution related effect. Apple varieties, of which there used to be hundreds, were originally induced by such random mutations. 

  The fact that there are dozens of these two faced leaves indicates that there is a whole freak branch up there promoting petiole partnering. Nature generally frowns on this kind of experimentation unless it produces some kind of benefit.  Maybe, just maybe, we are witness to the very beginnings of a successful biological adaptation that will lead to a whole host of stem sharing plants millions of years from now. Realistically, this trend won’t last any longer than a two headed calf.

    Now, in the category of a plain wonderful curiosity, I offer the fruit of Magnolia grandiflora.  When wandering about a city park on Roanoke Island, North Carolina this past September I came upon a beautiful specimen of a Southern Magnolia tree. This pyramidal shaped evergreen only grows in the warm coastal plain region from the Carolinas south to Florida to the Gulf States. Also known as the Bullbay tree, it is the official state tree of Louisiana.  The large leathery leaves and huge blooms are incredible enough, but I was fascinated by the bizarre fruit pods.  Take a look here at the freshly picked pod I borrowed from the tree.  This big (kitten sized) fuzzy thing was unlike anything this northern boy had ever seen.  I was going to make a sketch of it, but time and waning natural light forced me to resort to photographing it instead. 

  The fruit ended up coming home with us when we returned to Michigan, along with a whole box full of pine cones, nuts, crab shells, a preserved rattlesnake, and some unidentifiable shriveled thing.  I forgot about the magnolia pod for a few weeks and was delighted, upon rediscovery, to find it had gone to seed.  Technically this type of fruit is considered an aggregate of follicles or a burr made up of many small carpels which split to exude fleshy drupes.  Non-technically, each scale splits open and pushes out a bean sized Christmas -red seed.  These seeds, each about ½ inch long, are bright scarlet and shiny. They remain attached to the pod by a weak silky thread, so they hang out and angle slightly down. Take a look at this amazing fruit as it looked a week ago.

  Here is a true curiosity – an everyday thing that deserves a closer look.  In their native haunts, opossums, squirrels, and turkeys feast on these seeds with little appreciation for their beauty. A Native human Carolinian, Floridian, or Louisianan probably wouldn’t gawk at this thing like we might.  They are, after all, used to it.  I’ll bet there are a lot of ‘em, however, that don’t pay no nevermind to such things. 

  Be they bizarre or benign, curiosities should spark our curiosity no matter where we are from.

November 5, 2007

BaHum-bug

Filed under: Uncategorized — wykes @ 10:09 pm

  I cringe every year when the first television Christmas commercial comes out.  This year I found myself cringing about Nov. 1.  I’m not a curmudgeon (at least by my own definition), but I still believe that anything relating to the Christmas season shouldn’t make itself known until after turkey time. I believe that these ultra-early ads are somehow breaking some law of decency and that those breaking that law should be boiled in scented oil “with a stake of holly through their heart.” Bah Humbug.  We are all keenly aware that the season of joy and credit is just around the corner and don’t need Target to tell us so.  We have calendars. Admittedly, my reaction stems from the fact that I am unprepared, and will be, until Christmas Eve day.

  Mulling over such thoughts, I took a morning walk at Crosswinds Marsh to get in touch with the current season while it lasts.  According to my calendar, this is early November and I expect to see autumn leaves, large flocks of waterfowl, and a little frost.  With the air temperatures warming slowly into the upper thirties, I didn’t expect to see any active insects.  There was ample evidence of insect activity, however, and I encountered three examples that illustrate how some have prepared for the coming season.

  How is it that these minor beings are ready for something which they have never before experienced?  Instinct, that hard wiring which bypasses the learning mode, leads them through the necessary steps towards species survival.  It is patently untrue that insects start to prepare for winter when the weather gets cold.  They begin preparations months before while things are still warm and balmy.

  The Viceroy butterfly is a good example of this pre-preparedness. The first insect related thing I encountered was a tiny hibernaculum attached to a willow branch.  Take a look here and inspect the third leaf on the left.  Note that it is rolled into a tiny tube and attached to the branch via a silken safety harness. This structure was constructed by the Viceroy caterpillar while the leaves were still green and hearty.  The late summer brood of caterpillars start out as hungry as ever but they soon stop eating altogether.  Instead, they channel their chewing efforts into cutting out a leaf pattern for their winter home- like a tailor cutting cloth.  Most of the chosen leaf is cut away from the central vein and a stout layer of silk is laid down to secure it to the stem.  The remaining edges are bound together to form a tube.  The little architect then backs into his newly made capsule and remains there until summoned out the following spring. It enters into a resting state called diapause (a fancy name for the special kind of hibernation used by cold blooded animals) and survives with the aide of antifreeze chemicals in its blood.

  While the Viceroys survive winter as tiny larvae, the bagworm moths choose to overwinter as eggs.  About a quarter mile down the trail, I found this distinctive structure which gives the bagworm its name.  Take a look and you’ll see a suspended gray silk bag that looks, appropriately enough, like a Christmas ornament. Tiny bits of leaves and twigs are incorporated into the neatly crafted sack. Bagworm ornaments differ greatly in appearance depending on how the caterpillar makes use of the host plants (just for the heck of it, take a look here and here at a few more of these unique little constructions).

   Bagworms weave their protective sacs as soon as they hatch out in early summer and drag them about wherever they go. By August the larva are mature and they attach their mobile home to a twig with silk. They close up the front door and turn around inside, so as to point headfirst towards the ground, and they pupate.  When the adults emerge four weeks later in late September or early October, their lot in life has already been decided.  The males punch their way out and fly off in search of females.  The females enter the world without any wings and are little more than egg filled sacs of femininity. These desperate housewives will remain trapped within their bag house until an amorous male forces his way in and mates with her.  Once mated, she deposits the fertilized eggs inside the case and dies. Her eggs are well protected from the winter within the confines of the bag.

  My final encounter of the insect kind was only a tree over from the bagworm.  A very cold looking Damselfly was clinging to an Ash twig.  This female (see here) looked to be of a type known as a Familiar Bluet.  The males are the blue ones; although this brown female was turning a bit blue herself from the effects of the cold.  Her chosen technique of winter survival is to lay hundreds of eggs in the nearby marsh and allow the hatched nymphs to live in relative comfort under the ice. They will emerge next year to carry the torch of life. This individual is literally hanging on to her dwindling flame, but by doing so exhibits a remarkable ability to withstand freezing weather. Warmed by the rising sun, she will summon up her reserves and fly about until the next killing freeze ends her brief career.

  The damselfly, bagworm, and viceroy have prepared well for the inevitable.  Likewise, we too must brace ourselves for the Macy’s parade.

November 3, 2007

Do Leaves Retire?

Filed under: Uncategorized — wykes @ 9:41 pm

 The woods were very still yesterday morning.  There had been a killing frost the night before and the rising sun was quickly wiping it away.  A few ice crystals sought refuge in the long shadows.  Most of the trees had already shed their sheltering leaves, so the sun advanced with unencumbered rapidity on its daily mission. Though the branches of the sassafras, walnut, willow, ash and elm were bare, the stubborn red maples and oaks were still desperately clinging to their wardrobes.

  Walking through this scene I was impressed with the sense that nature was holding her breath for a moment.  A Red-bellied Woodpecker chortled in the distance and a Fox Squirrel set about with a series of guttural barks, but otherwise the place was hushed.  There was no breeze. Only the soft crunch of my footsteps disturbed the scene. I stopped for a moment when a movement caught the corner of my eye.  A single maple leaf slowly descended to earth via a random butterfly like path.  It gently bounced off a black cherry twig and slid over the surface of a spicebush leaf before reaching the ground.  Each aerial contact gave off a light ticking sound but the final landing was silent. Soon a small flock of leaves started to fall.  Prompted only by the invisible forces of gravity each leaf took its own flight path.  One fluttered like a small bird while another maintained an even keel as it dropped straight down. Soon the place was raining maple leaves and the woods came alive with horizontal motion. Then, after only a few dozen seconds, everything stopped and the stillness resumed.

  I believe it was my presence that set off that morning flight.  No, I’m not saying that the trees were actually aware of my nearness but that I set up some vibration that triggered the release of one leaf. That leaf in turn triggered the others and so on. Yoda would claim that I tripped the wires of “the force,” but I know not of such things. I do know that the wind took over the disturbance role by day’s end and that a good portion of the maple leaves made their final journey yesterday.  The oaks, of course, held firm.

  Witnessing the fall of a single leaf, let alone causing it, is a small experience in a big world. We all know that deciduous trees shed their leaves but may take the whole process for granted.  Being there when an individual leaf dies is a bit humbling.   True, the death of a leaf is not as heart wrenching as that of a favorite pet, but it does cease to be living tissue and so fits the definition. The tree needs to release the leaves so that it can continue living. The tree is in control of the whole situation and leaves (no pun intended) only the final moment to the whims of chance.

  It’s all about abscission.  Over the course of the year a maple leaf – or any other tree leaf for that matter – hosts chlorophyll which manufactures food for the tree.  Triggered by the shortening days, reduced light intensity and lower temperatures, the parent tree begins to prepare for the onset of winter. In the waning days of summer and early fall, the leaf can’t convert the sun’s energy as efficiently as it used to. The tree, in other words, uses up the additional food as fast as it’s made.  Also, since water evaporates off the leaf surface, the tree starts to loose more water than it can afford. The drying effect of winter is the reason trees shed their leaves.

  At this point, the tree starts to cut its losses and draws essential liquids and food reserves back down into the winter-safe realm of the roots.  All the nutrients, minerals and sugars are pulled back from the leaves.  The point where the leaf connects to the stem is called the abscission layer (take a look at this micro photo of a maple leaf abscission layer).  Normally the cells in this area act like a sponge full of tiny vessels to transport fluids to and from the leaf.  In the fall, these cells start to swell and exude a waxy substance which cuts off the vessel flow. Deprived of the tiny lifelines, the chlorophyll dies and the bright autumn colors are exposed (we’ve been through this part before).  The leaf is gets old and literally enters its golden years. It is a brief retirement.

  Instead of a gold watch, the parent company forms a corky layer to cover the scar created by the dying leaf and essentially locks the leaf out for good.  The abscission layer eventually breaks down completely leaving only the skeletal transport tubes to hold the leaf to the stem. The rest is up to chance.

  All it takes is a puff of breeze, a footstep vibration, or a squirrel’s sneeze to create a force load that exceeds the strength capacity of the frail tubes.  The moment this last connection is compromised is the moment a leaf is sent to earth. Think about that next time you see a leaf die.

November 1, 2007

A Better Mouse

Filed under: Uncategorized — wykes @ 9:16 pm

 Now that the kids are away at school, I have the opportunity to be the first one to enter the kitchen in the morning.  My wife frequently beats me there and has the coffee on even before I rise, but last week I was first. Granted, this is neither a remarkable thing nor a great accomplishment, but it was a matter of fortuitous timing. I rounded the corner of the refrigerator and was greeted by the sight of a mouse sliding across the floor. It was in the process of making all due haste toward the security of the laundry room but its tiny feet were not gripping the smooth surface. Apparently I came upon it so suddenly that it popped a wheelie and slid sideways before gaining traction and making good on its escape.

  My mumbled verbal reaction was a simple “now that’s odd.” I don’t usually jump at the sight of scurrying things unless they are of the spider persuasion – and that’s an uncontrollable thing on my part. Mice don’t bother me at all.  The odd part about this encounter was that the uninvited guest was a mouse to begin with.  Over the past 20 years the only regular irregular mammalian invaders in this house have been short-tailed shrews.  These micro predators feed on insects and spiders, so their presence is welcome in my view. When one is in the house, I may neglect to mention the fact to my wife in lieu of other more important things.  Somehow, however, the tiny life form manages to reveal itself to her. Because she is not appreciative of their presence, I am pressured into setting the “jaws of death” and ending its career.

  By the long tail and white belly, I knew the skidding mouse to be either a Deer Mouse or a White-footed Mouse.  House mice, those immigrants from Europe, are glossy gray all over and do not have a white belly or feet.  Stuart Little was a House Mouse as were those albino mice running the universe in “A Hitchhiker’s Guide to the Universe.” Unlike the House variety, both the Deer and White-footed Mice are outdoor creatures that do not make a regular habit of living inside our dwellings. I expected the creature to re-enter the wild, so I made no mention of the mouse whatsoever. 

  I gave it a few days to depart.  In the meantime I maintained my wife in a state of ignorance, but felt like I was cheating on her somehow. On the third day, I rose again (seems like I’ve heard that phrase before…gee, I hope I don’t get hit with a plagiarism suit). After two mornings of expecting to hear a scream from the kitchen, I decided to quietly set the “jaws of death” just to make sure things were back to normal.  I guess I still harbored some resentment stemming from a long ago incident in which a gang of mice made a nest out of my set of prize Webelos scout ribbons.  They chewed them into oblivion and made a fuzzy retreat out of my childhood.

  On the next morning, I heard a loud squeak from the kitchen.  It was my wife.  “There’s a mouse in a trap right inside the laundry room door,” she half screamed, “please get it out.” I performed the solemn task incompletely. I actually placed the stiff little bug-eyed corpse out in the unheated back porch until I could look at it better, but claimed that it was “taken care of.”  It’s shameful how such a thing can lead to a life of deceit.

  I should mention that my dependable “jaw of death” is a steel toothed McGill trap.  I’ve had it for years and have never had to resort to a regular snap trap.  It’s a self setting thing that clicks into position when the back springs are squeezed.  A little peanut butter on the trigger and you’ve got the makings for a quick trip to shrew, or in this case mouse, heaven. Building a better mousetrap has always been an obsession for inventors since the first human (probably a female) spotted the first proto-mouse running out from under the mammoth hide.  Aside from neck snapping wires & jaws, many of these creations employed drowning tanks, magical flip doors, and dead falls. Electrocution and even loaded mini-pistols have been employed in this deadly task. I can’t resist showing you this old standby: an old wooden Victor four hole trap that was popular in the early half of the last century (see it here). 

  The trusty old McGill trap effectively provided an answer to my mouse identity question.  My dear little departed was indeed a White-footed Mouse. I took a short time to sketch the beast and posed it in a typical life posture of cleaning itself (see it here).  You’ll notice that these mice are attractively pelted with a bright white belly and cinnamon brown sides. The feet are covered with fine white fur, but appear pink upon close examination. One of the big differences between this and the look-alike Deer Mouse is that Deer Mice have a very clear border line dividing the dark upper side and the white under portion of the tail, while the White-foot has a hazy dividing line.  O.K. that’s not much of a difference, but unless you have the time and desire to measure the feet and the third upper molar, that will have to do.

  In nature White-foots are semi-arboreal. This means that they can and will climb trees.  Their long tails come in handy as balancing tools when traversing thin branches.  As a matter of fact, they often roof over old bird nests in order to convert them into winter homes.  Perhaps the most surprising thing of all is their musical talent.  Both Deer and White-foots will squeak with ultrasonic delight, but they also are known to drum their tiny paws upon dry grass stems or leaves to create a melodic buzzing sound.  

  Why they do this drumming is somewhat of a mystery, but I prefer to think of it as part of an eternal death chant. Although there are extreme records of captive mice putting three candles on their birthday cakes, the average life span in the wild is less than a year.   Only 5% of the mice born in a particular year – and there are a lot of them – survive into the following year. 

  Mice are born to be eaten or killed by nearly every other life form on earth.  As one of those life forms it was my job to perform my ecological and spousal responsibility. I ate the mouse with full knowledge that the circle of life had been completed. O.K., I didn’t eat the mouse, I was just trying to end this thing on a philosophical note.  I promise not to lie about mice or shrews again…at least in the near future.

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