[you might need to boost the volume a bit on this one]
© 2015 Next-Door Nature—no reprints without written permission from the author (I’d love for you to share my work but please ask). Thanks to these photographers for making their work available through a Creative Commons license (CCL) or Project Guttenberg License (PGL) (from top to bottom): USFWSmidwest (eastern gray treefrog); Jimmy Smith (field cricket); Lisa Brown (common true katydid); Rachid H (common meadow katydid); Roger Engberg (dog-day cicada); Andy Reago & Chrissy McClarren (northern cricket frog); AllieKF (American toad); Matt Reinbold (green frog); J. N. Stuart (boreal chorus frog); USFWSmidwest (eastern gray treefrog).
Once upon a time there was a damsel(fly).
[Imagine, if you will, a bucolic Disneyesque soundtrack of flutes and piccolos in the background.]
She (Or maybe he. This is a modern fairly tale.) explored the lovely little pond from which s/he had recently emerged after having spent most of life underwater as a nymph.
Who would have guessed during that awkward adolescence, when growth spurts had him/her literally jumping out of her skin a dozen times or so, that she would transform from an ugly duckling into a swan? (Speaking of awkward… let’s just stick with “her” from here on out for the sake of simplicity, shall we?)
So… today was her debut. A coming out, of sorts, and the damsel(fly) flitted here and there, enjoying the warm sun shimmering and gleaming on her iridescent wings as she dipped down to the water now and again to daintily snack on mosquito larvae.
Not a care in the world. Completely oblivious to… [Cue the ominous bassoon music] …the looming presence of a dragon(fly) on the other shore.
Not that it mattered, really. [Can I have the flutes and piccolos back, please?] Sure, the dragon(fly) was part of the Epiprocta clan, the damsel(fly) a Zygoptera, but they were both members of the Order Odonata. No family feuds that she knew of, and so closely related were they that many folks had trouble telling one from the other without assistance in the form of a handy reference table.
They were cousins, but not kissing cousins. No interspecies hanky-panky here, even though their kind were known as having an unusual approach to romance. You see, instead of offering a wake-up kiss, the male clasps the female behind her head with a special appendage on the tip of his abdomen. IF she welcomes the embrace, instead of sliding her foot into a size 6 glass Louboutin slipper eventually she loops her abdomen forward to pick up the spermatophore from a structure on his abdomen and deliver it to her spermatheca [Latin is a romance language, remember].
I know, I know… it sounds kind of weird and kinky but trust me, it’s just hard to describe. When it’s right it’s a beautiful thing, especially when the couple forms a kind of heart with their entwined bodies [Everyone say “awwwww”].
Sometimes they even become members of the Mile-High Club, flying united for a little while. But damsel(flies) and dragon(flies) aren’t the marrying kind. They’re independent and self-sufficient—a characteristic that begins in infancy. Good thing, too, because, to be perfectly honest, the adults are neglectful parents. Dad is no prince, zooming off with hardly a backward glance at the new Mom-to-be, who’s no queen of the nursery herself. She deposits her eggs in floating plants or directly into the water and then washes her (metaphorical) hands of the responsibilities of child-rearing.
The nymphs (aka naiads) hatch and, being carnivorous little monsters, begin feeding on mosquito larvae, daphnia, tadpoles, small fish, and sometimes each other.
That happens among adults as well, although the jury’s still out on the subject of postcoital cannibalism, a not-uncommon behavior in the insect world. It’s enough to give a girl pause (although, for most insect species it’s the guy who needs to worry about fatal attractions).
Whatever. This is the 21st century and females of every stripe and species are all about DIY. Gals today don’t need a prince to save them. Locked up in a tower? Any modern, self-respecting damsel knows you simply pull out your smartphone, Google instructions for making a rope out of sheets, and then shimmy down to freedom.
Evil stepmother? Please. Dial the Child Abuse Hotline and tell that witch you’ll see her in court!
Face to face with a dragon? Reach for your trusty catch-pole or tranquilizer dart gun apps.
And live happily ever after.
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© 2012 Next-Door Nature—no reprints without written permission from the author (I’d love for you to share my work; all you have to do is ask). Thanks to these photographers for making their work available through a Creative Commons license: [starting from the top]: Tomquah (cover damselfly); Photo munki (nymph… not the same species); Clifton Beard (mating damselflies); Ben McLeod (dragonfly eyes); and Charles Lam (damselfly eyes).
Grab forty winks. Saw logs. For a species that’s habitually short on shut-eye, we humans sure have come up with myriad ways to talk about it. We also spend a lot of time and money studying sleep, or the lack thereof. Yet, in spite of decades of inquiry, researchers still don’t have a good fix on why we—and just about every other living creature—need to nod off. We’ve had better luck trying to understand other unconscious states, especially those employed by certain non-human species to deal with hard times.
Winter poses a critical challenge for animals who stay put rather than migrate to warmer climes. Thermoregulation requires calories, but many foods—especially fruits, nectars, vegetation, and insects—are scarce when the days are short. The ability to reduce one’s energy needs can be a life-saving adaptation. Hibernation does just that—it lowers an animal’s metabolic rate. If all goes well, this period of inactivity, which may last several days, weeks, or even months, depending on the species, will stretch stored energy reserves (aka body fat) long enough for the animal to survive until a greener season. “If” depends on many factors, such as the abundance of autumn food resources, the length and severity of cold days, and even the stability of the den site during repeated freeze-thaw-freeze cycles.
When a critter—let’s use the chipmunk (Tamias spp.) as an example—transitions into a state of hibernation, its body temperature drops to near freezing, breathing becomes so shallow as to be imperceptible, and the heart rate decreases dramatically, from 350 to 4 beats per minute. Although we tend to think of hibernation as a season-long slumber, chippies and other hibernating rodents do wake up every few weeks to have a snack and take a potty break, even though these periods of activity, called interbout arousals, consume up to 90% of stored body fat. There are some champion nappers in this chisel-toothed group—including the groundhog (aka woodchuck, Marmota monax), who sleeps half its life away, setting the alarm for March when it heads to bed in September.
Other examples of sound sleepers include: insectivores like the European hedgehog (Erinaceus europaeus) and the tenrecs (Microgale spp.); the mountain pygmy possum (Burramys parvus)—the only hibernating marsupial; and the echidna (Tachyglossus spp.), a monotreme. Biologist recently added the mouse lemur (Microcebus spp.) and the fat-tailed dwarf lemur (Cheirogaleus medius) to the hibernator roster; prior to this discovery, we didn’t have any examples from among the primates. Additionally, since winter temperatures in their native Madagascar may reach 86° F (30° C), it’s become clear that hibernation isn’t strictly associated with cold weather. Nor is it limited to mammals; a bird called the common poorwill (Phalaenoptilus nuttallii) snoozes through at least some of the snowy season.
Ironically, that most famous of North American sleep icons, the bear (Ursus spp.), is the subject of much debate. The question is whether or not they are “true hibernators.” Bears often spend far more time sleeping than the so-called “trues,” so what’s all the fuss about? Well, this is going to sound like nit-picking, but here goes. First of all, a bear’s heart rate drops, but not quickly enough to suit some scientists. Also, while the number of heartbeats may go as low as 8 per minute, the average is closer to 50 per minute. Moreover, during this time the bear’s body temperature remains pretty close to normal. This is a handy little idiosyncrasy that, should the need arise, allows the animal to wake up fast… and often cranky—a fact Santa (and anyone else) should keep in mind when planning a mid-winter visit to the den.
Taking to one’s bed for months on end could be seen as a rather over-the-top response to a simple cold front. It smacks of swooning characters in English romance novels from the late 1700s. Frankly, it’s not everyone’s cup of tea, and many wild critters take a more measured approach. Torpor is the term commonly used to describe these shorter, less dramatic forms of dormancy, although, technically, hibernation and other types of suspended animation are really subsets of torpidity. Call it what you will, there are examples of “temporary hibernation” in all the Classes of vertebrate animals—mammals, birds, reptiles, amphibians, and fish—and it’s commonplace among the myriad spineless critters.
For some of the busiest bodies, torpor is a daily habit. Hummingbirds (Trochilidae), for example, have such a high metabolic rate that they need to ingest a steady stream of non-carbonated sugar water (i.e., nectar) during their waking hours or they’ll become hypoglycemic and are too exhausted to fly. Can’t fly? Can’t feed. It’s a vicious circle that will ultimately lead to the bird’s death without some kind of intervention. As you might imagine, this need to constantly refuel creates an enormous problem when night falls and these feathered perpetual motion machines must rest. Without some way to temporarily lower their metabolic rate, hummingbirds would never be able to get out of bed in the morning. Never fear—torpidity to the rescue!
Swifts (Apodidae), chickadees (Paridae), nightjars (Caprimulgidae), and doves (Columbidae) are just a few of the other avian species who go torpid under various conditions. Generally speaking, these birds are fruit-, nectar-, or insect-eaters, and they tend to be on the small side (less than 80g). The snowy owl (Bubo scandiacus), at 1600-2950g is one exception to this rule, and biologists recently added a second, when it was confirmed that the tawny frogmouth (Podargus strigoides) goes torpid during Australian winters. Personally, I find these new insights into animal behavior thrilling, because they reassure me that what we know about wild creatures is still a drop in the bucket compared to what we don’t know—there are worlds upon worlds waiting to be discovered on this blue gem of a planet we call home.
Of course, cold is not the only hardship wild things would rather sleep through. Periods of drought are just as serious a threat to survival, especially for aquatic and semi-aquatic species. When a lake, pond, or stream goes dry, the inhabitants need to dig in. Literally. Turtles and tortoises (Testudines), crocodiles (Crocodylidae), frogs and toads (Anura), salamanders (Caudata), and some crustaceans will aestivate (also spelled estivate)—a drought-driven form of hibernation. They sink down into the mud before it dries completely, sealing themselves in a mucous capsule until the rains come again. If ever there was a time to be glad you can absorb oxygen in the soil through your skin, this is it, because the air in your boggy bubble won’t last very long.
Researchers are intrigued by these alternate forms of sleep and how they might offer clues for solving a variety of human health concerns. Honestly, I understand their fascination but I don’t know how they stay awake long enough to collect any data. Just writing about dormancy has my eyelid feeling so… heavy. I guess it’s… time for…. me to turn… in.
…..Hit the YAWN! hay.
*Pop Quiz: How many times did you yawn while reading this? 😉
There’s nothing quite as invigorating as finding a little Next-Door Nature in your email inbox—click the “subscribe” link in the upper right-hand corner of this page and receive notifications of new posts!
© 2011 Next-Door Nature—no reprints without written permission from the author. Thanks to these photographers for making their work available through a Creative Commons license: SearchNetMedia (prairie dog); Pau Davidy (polar bear); Tatiana Bulyonkova (rock dove); Michael Ransburg (turtle); and Pat Gaines (snowy owl).
“Oh look—you’ve got a visitor!”
Standing outside my front door, Bryan, pet-sitter extraordinaire, was in a better position to spot that wisp of green. But coming or going, I doubt I’d have noticed on my own. A habitual multitasker, I’m often doing one thing while thinking about the next three. Not the best frame of mind if you want to notice a recently hatched praying mantis nymph near your doorknob.
That one-inch explorer wasn’t missing much, I assure you. I leaned in for a closer look, but s/he had the advantage: two large compound and three simple eyes packed onto a triangular-shaped head that can—and did—swivel nearly 180 degrees.
Earth is home to more than 1,800 species of mantids. I’m pretty sure this youngster was a Carolina mantid (Stagmomantis carolina), the only species native to North America. As I’ve mentioned before, though, I’m not as familiar with the spineless members of the Animal Kingdom, so it could just as easily have been a European mantid (Mantis religiosa) or a Chinese mantid (Tenodera sinensis), both accidentally introduced to this continent about 100 years ago.
The common name derives from the front legs, which are usually folded into a position that someone interpreted as devotional. Devoted to dinner might be a more appropriate assumption. The spiked forelimbs are better suited to predation than piety, with reflexes so lightning-quick as to appear supernatural to the unaided eye. While they commonly feed on a variety of other insects, large adult mantids have been known to capture and consume hummingbirds and tree frogs. No wonder they are often mistakenly (yet accurately) called preying mantises.
Unlike the truly prolific members of the insect clan, mantids produce a single generation each year. Nymphs hatch in late spring or early summer and are fully grown by late summer. In autumn, females find a stick, a stem or even a building and deposit a frothy mass that hardens to protect the eggs inside. The adults die soon after, of old age or exposure, and the eggs overwinter in their protective case.
When the nymphs emerge they look like miniature versions of their parents and begin to search for something to eat. Often, the fastest food is a sibling—cannibalism is common in the insect world and mantids are no exception.
Survivors of the initial feeding frenzy disperse, blending into green and brown foliage so well you may have to take their presence on faith… unless one just happens to be drawn to the winged activity beneath a light near an apartment door, where s/he is easily visible to an alert, undistracted nature enthusiast.
The stairwell of my apartment building is shaded in the morning and, with only two simple eyes at my disposal, I needed more light. So I held out a stick, hoping this familiar substrate would help me coax the nymph to climb onboard. Instead, the little swashbuckler leapt onto my wrist like a pirate swinging from the rigging of a ship, and I was instantly transformed from a biologist into a boat for a tiny, curious captain in a prayerful pose whose head pivoted port and starboard as we sailed into the sunshine.
And I was thankful.
© 2011 Next-Door Nature— no reprints without written permission from the author. Thanks to Larry Salveson for making his photo of a female mantis laying eggs available through a Creative Commons license.
This week’s focus on the holidays of two major religions, not to mention some events in my own life, had me thinking about endings that actually turn out to be the start of something new and unexpected. My spiritual vocabulary is more deeply rooted in the biological than the Biblical, so when I think of metamorphosis and renewal, I think of Lepidoptera.
Butterflies and moths are the very model of adaptation, moving through many transformations during the course of their lives. These shape-shifters begin life as an egg. With the possible exception of avid gardeners, most of us don’t often see, or at least notice, this stage. Once they emerge as caterpillars though, their bright colors, wild patterns, and wavy gait are eye-catching, as are the web-tents spun by certain species shortly after they hatch. Moth caterpillars are usually fuzzy, so if you find one that’s smooth, you’ve probably got a future butterfly on your hands.
And speaking of hands… before you start picking up caterpillars, you should know that some of them sting. Their fuzz includes hollow quills connected to poison sacs; when touched, reactions can range from mild itchiness to severe pain, dermatitis, or even more systemic problems. I’m speaking from personal experience here, and this is a rather embarrassing confession. It’s no secret that most wild creatures try to blend into their surroundings, so when you see a brightly colored, very conspicuous animal, there’s a good chance it has a more than adequate defense system. A wildlife biologist, of all people, should know that. I do, and I did. But I had never seen a Io moth caterpillar before and wanted a closer look. My curiosity got the better of me and I let down my guard. Only after I had allowed it to crawl onto my hand did I begin to think, “Hmmm… probably not a good idea.” Good ol’ hindsight… always there just after you need it.
But I digress.
Caterpillars continue their quick-change artist life with five molts, called instars, during which they wriggle out of their too-tight skin. Finally, they find a place to hang out for a while and a different kind of skin, called a chrysalis, forms. Moth caterpillars usually prefer the added protection of a silken cocoon.
Inside the chrysalis/cocoon, a radical transformation takes place, something miraculous, even when you realize it can all be explained biologically. A death, of sorts, that must take place for something new to be born. A leap of faith. Does the caterpillar know, somewhere deep down in its DNA, that there’s more to life than being an earth-bound eating machine? Do caterpillars dream of life on the wing?
Now that I’m in my 50s, I’m starting to realize I’ve got quite a lot in common with Lepidoptera. I’ve experienced my own series of instars, breaking out of old skins when they became too restrictive and claustrophobic. And there have been times spent in the cocoon as well, wondering what, if anything, lies ahead, and how much longer I’ll have to wait to find out. Life, after all, is about taking chances… letting curiosity, excitement, optimism and wonder take the lead over caution, even if that means sometimes you get stung. I haven’t yet managed to escape the law of gravity, but I’m still dreaming of flight.